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U.S. Leading Causes of Death and Years of Potential Life Lost, 1981-2019: Implications for Surgical Research

  • Allen Wang
    Affiliations
    Center for Pediatric Trauma Research, The Abigail Institute at Nationwide Children's Hospital, Columbus, Ohio

    Center for Injury Research and Policy, The Abigail Institute at Nationwide Children's Hospital, Columbus, Ohio
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  • Henry Xiang
    Correspondence
    Corresponding author. The Abigail Institute at Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH 43205. Tel.: +1 614 355 5893.
    Affiliations
    Center for Pediatric Trauma Research, The Abigail Institute at Nationwide Children's Hospital, Columbus, Ohio

    Center for Injury Research and Policy, The Abigail Institute at Nationwide Children's Hospital, Columbus, Ohio

    Department of Pediatrics, The Ohio State University College of Medicine, Columbus, Ohio
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Published:August 06, 2022DOI:https://doi.org/10.1016/j.jss.2022.06.071

      Abstract

      Introduction

      Examining burden of diseases could shed light on priorities of public health interventions and research funding. This study examined trends of the U.S. top leading causes of death from 1981 to 2019 using the total number of deaths, age-adjusted death rate, and years of potential life lost (YPLLs).

      Methods

      Data were from the Web-based Injury Statistics Query and Reporting System. This study gathered total number of deaths, age-adjusted death rates per 100,000 people, and YPLLs under 70 y of age (YPLL-70) from 1981 to 2019 for the top 10 leading causes of death and human immunodeficiency virus/acquired immunodeficiency syndrome (AIDS) for each year. The 39 y from 1981 to 2019 were evenly divided into three study periods: 1981-1993, 1994-2006, and 2007-2019. The percent change of YPLL-70 over three time periods for the top ten leading causes of death and AIDS was calculated. Trends of age-adjusted death rates and YPLL-70 of the top five leading causes of death based on the 2018-2019 death data were also reported by graphing them against time from 1981 to 2019 to highlight major mortality causes. Age-adjusted death rates for the top five leading causes of deaths and the National Institutes of Health (NIH) annual funding level in 2019 were graphed together to illustrate funding discrepancy in injury research and prevention.

      Results

      The total number of deaths caused by malignant neoplasms in 2019 was 244,994, followed by 183,442 deaths of heart diseases, 121,476 deaths of unintentional injuries, and 41,051 suicide deaths. Despite an initial -22.20% drop of YPPL-70 during 1981-1993, unintentional injuries experienced significant increases of 19.38% and 18.59% of YPLL-70 in 1994-2006 and 2007-2019, respectively. The age-adjusted death rate for unintentional injuries was 1182 per 100,000 people in 2019, and the NIH funding in the same year was $897 million. In comparison, the age-adjusted death rate for cancer, heart disease, and human immunodeficiency virus/AIDS was 786, 649, and 30 per 100,000 people while the NIH funding was $2,560, $2,394, and $3037 million, respectively.

      Conclusions

      Unintentional injuries, suicide, and homicide were consistently among the top leading causes of death and YPLL-70, so they should be prioritized in public health planning, research, and federal funding allocation. Injury and trauma research is severely underfunded by the U.S. premier funding agency.

      Keywords

      Introduction

      A systematic and regular analysis of trends of the burden of disease and leading causes of death is important and highly recommended by researchers.
      • Ma J.
      • Ward E.M.
      • Siegel R.L.
      • Jemal A.
      Temporal trends in mortality in the United States, 1969-2013.
      Comprehensive examination of leading causes of death could be informative for health program development, research planning, and prioritization of federal and state funding allocations.
      • Ballreich J.M.
      • Gross C.P.
      • Powe N.R.
      • Anderson G.F.
      Allocation of national institutes of health funding by disease category in 2008 and 2019.
      • Gillum L.A.
      • Gouveia C.
      • Dorsey E.R.
      • et al.
      NIH disease funding levels and burden of disease.
      • Gross C.P.
      • Anderson G.F.
      • Powe N.R.
      The relation between funding by the National Institutes of Health and the burden of disease.
      • Rees C.A.
      • Monuteaux M.C.
      • Herdell V.
      • Fleegler E.W.
      • Bourgeois F.T.
      Correlation between national institutes of health funding for pediatric research and pediatric disease burden in the US.
      Measurements such as incidence and prevalence of disease, hospital utilization, total number of death, age-adjusted death rate, and years of potential life lost (YPLLs) have been used in previous studies.
      • Gross C.P.
      • Anderson G.F.
      • Powe N.R.
      The relation between funding by the National Institutes of Health and the burden of disease.
      ,
      Centers for Disease Control and Prevention (CDC)
      Years of potential life lost before age 65--United States, 1990 and 1991.
      Centers for Disease Control and Prevention (CDC)
      Firearm-related years of potential life lost before age 65 years--United States, 1980-1991.
      • Dowd B.
      • McKenney M.
      • Boneva D.
      • Elkbuli A.
      Disparities in National Institute of Health trauma research funding: the search for sufficient funding opportunities.
      • Woolf S.H.
      • Schoomaker H.
      Life expectancy and mortality rates in the United States, 1959-2017.
      The total number of deaths and the mortality rate often increase with age, so these two measurements inherently emphasize death at the oldest ages.
      • Bui A.L.
      • Coates M.M.
      • Matthay E.C.
      Years of life lost due to encounters with law enforcement in the USA, 2015-2016.
      Although the age-adjusted death rate specifically controls for age-related differences across age distributions, YPLL approximates the years of potential life lost in premature death by subtracting the age of death from the average life expectancy.
      • Arcà M.
      • di Orio F.
      • Forastiere F.
      • Tasco C.
      • Perucci C.A.
      Years of potential life lost (YPLL) before age 65 in Italy.
      • Borse N.N.
      • Rudd R.A.
      • Dellinger A.M.
      • Sleet D.A.
      Years of potential life lost from unintentional child and adolescent injuries--United States, 2000-2009.
      • Rumisha S.F.
      • George J.
      • Bwana V.M.
      • Mboera L.E.G.
      Years of potential life lost and productivity costs due to premature mortality from six priority diseases in Tanzania, 2006-2015.
      Researchers argue that public health program development and funding decision efforts should focus on preventing premature death. Therefore, YPLLs should be used to make decisions about setting intervention priorities and allocating scarce resources.
      • Ballreich J.M.
      • Gross C.P.
      • Powe N.R.
      • Anderson G.F.
      Allocation of national institutes of health funding by disease category in 2008 and 2019.
      ,
      • Gross C.P.
      • Anderson G.F.
      • Powe N.R.
      The relation between funding by the National Institutes of Health and the burden of disease.
      ,
      • Bui A.L.
      • Coates M.M.
      • Matthay E.C.
      Years of life lost due to encounters with law enforcement in the USA, 2015-2016.
      In fact, YPLLs have been used around the world for identifying leading causes of death as well as for assessing funding allocations.
      • Ballreich J.M.
      • Gross C.P.
      • Powe N.R.
      • Anderson G.F.
      Allocation of national institutes of health funding by disease category in 2008 and 2019.
      ,
      • Gross C.P.
      • Anderson G.F.
      • Powe N.R.
      The relation between funding by the National Institutes of Health and the burden of disease.
      ,
      • Rees C.A.
      • Monuteaux M.C.
      • Herdell V.
      • Fleegler E.W.
      • Bourgeois F.T.
      Correlation between national institutes of health funding for pediatric research and pediatric disease burden in the US.
      ,
      • Bui A.L.
      • Coates M.M.
      • Matthay E.C.
      Years of life lost due to encounters with law enforcement in the USA, 2015-2016.
      ,
      • Rumisha S.F.
      • George J.
      • Bwana V.M.
      • Mboera L.E.G.
      Years of potential life lost and productivity costs due to premature mortality from six priority diseases in Tanzania, 2006-2015.
      ,
      • Paciej-Gołębiowska P.
      • Pikala M.
      • Maniecka-Bryła I.
      Years of life lost due to diseases of the digestive system in Poland in 2000-2014.
      Previous studies have examined relationships between the burden of disease and the top leading causes of death with National Institutes of Health (NIH) funding allocation.
      • Ballreich J.M.
      • Gross C.P.
      • Powe N.R.
      • Anderson G.F.
      Allocation of national institutes of health funding by disease category in 2008 and 2019.
      • Gillum L.A.
      • Gouveia C.
      • Dorsey E.R.
      • et al.
      NIH disease funding levels and burden of disease.
      • Gross C.P.
      • Anderson G.F.
      • Powe N.R.
      The relation between funding by the National Institutes of Health and the burden of disease.
      • Rees C.A.
      • Monuteaux M.C.
      • Herdell V.
      • Fleegler E.W.
      • Bourgeois F.T.
      Correlation between national institutes of health funding for pediatric research and pediatric disease burden in the US.
      ,
      • Dowd B.
      • McKenney M.
      • Boneva D.
      • Elkbuli A.
      Disparities in National Institute of Health trauma research funding: the search for sufficient funding opportunities.
      Mortality, YPLLs, and disability-adjusted life years (DALYs) were found to be significantly associated with the NIH funding for a particular disease category, while incidence, prevalence, and hospital length of stays were not.
      • Gross C.P.
      • Anderson G.F.
      • Powe N.R.
      The relation between funding by the National Institutes of Health and the burden of disease.
      Some researchers argue that injury prevention and trauma care research is not adequately supported by the NIH funding based on age-adjusted death rate, YPLLs, and DALYs.
      • Dowd B.
      • McKenney M.
      • Boneva D.
      • Elkbuli A.
      Disparities in National Institute of Health trauma research funding: the search for sufficient funding opportunities.
      ,
      • Glass N.E.
      • Riccardi J.
      • Farber N.I.
      • Bonne S.L.
      • Livingston D.H.
      Disproportionally low funding for trauma research by the national institutes of health: a call for a national institute of trauma.
      Others criticize NIH funding prioritization by showing mismatch between top disease burdens in the society and NIH disease-specific research funding allocation. Ballreich et al. reported in 2021 that NIH research spending was based primarily on the level of NIH spending more than 10 y earlier despite burden of disease in the United States having dramatically changed.
      • Ballreich J.M.
      • Gross C.P.
      • Powe N.R.
      • Anderson G.F.
      Allocation of national institutes of health funding by disease category in 2008 and 2019.
      Woolf and Schoomaker investigated U.S. life expectancy and mortality rates from 1959 to 2017 and reported that there was an overall increase in life expectancy over past decades until 2014.
      • Woolf S.H.
      • Schoomaker H.
      Life expectancy and mortality rates in the United States, 1959-2017.
      A decrease of U.S. life expectance after 2014 was reported, and the main contributor has been identified as the mortality increase from drug overdoses and suicides among young and middle-aged adults of all racial groups.
      • Woolf S.H.
      • Schoomaker H.
      Life expectancy and mortality rates in the United States, 1959-2017.
      The alarming decrease of life expectance warrants an examination of the top leading causes of death over time using age-adjusted death rates and YPLLs. Ma et al. investigated temporal trends in U.S. mortality from 1969 to 2013 and concluded that an overall decreasing trend in the age-standardized death rate for all causes combined, heart disease, cancer, stroke, unintentional injuries, and diabetes.
      • Ma J.
      • Ward E.M.
      • Siegel R.L.
      • Jemal A.
      Temporal trends in mortality in the United States, 1969-2013.
      Ma's study did not cover the years after 2013, the period in which other researchers reported significant increase of deaths caused by unintentional injuries and suicide.
      • Woolf S.H.
      • Schoomaker H.
      Life expectancy and mortality rates in the United States, 1959-2017.
      Prior studies assessing NIH disease-specific research funding reported injuries as one of the top leading causes of deaths, years of life lost, and DALYs
      • Ballreich J.M.
      • Gross C.P.
      • Powe N.R.
      • Anderson G.F.
      Allocation of national institutes of health funding by disease category in 2008 and 2019.
      • Gillum L.A.
      • Gouveia C.
      • Dorsey E.R.
      • et al.
      NIH disease funding levels and burden of disease.
      • Gross C.P.
      • Anderson G.F.
      • Powe N.R.
      The relation between funding by the National Institutes of Health and the burden of disease.
      • Rees C.A.
      • Monuteaux M.C.
      • Herdell V.
      • Fleegler E.W.
      • Bourgeois F.T.
      Correlation between national institutes of health funding for pediatric research and pediatric disease burden in the US.
      ; however, injury/trauma care research and the underfunding were rarely mentioned in their discussion. Dowd et al.
      • Dowd B.
      • McKenney M.
      • Boneva D.
      • Elkbuli A.
      Disparities in National Institute of Health trauma research funding: the search for sufficient funding opportunities.
      used the total number of trauma deaths from 2007 to 2017 and the annual NIH funding in 2015, 2018, and 2019 to highlight underfunding of injury/trauma research and advocated for a re-evaluation. One major limitation of the study by Dowd et al. is that the raw number of trauma deaths did not consider population growth or the age distribution shift of the U.S. population. These deficiencies and the knowledge gap about potentially shifted top leading causes of U.S. deaths and YPLL in the past decades hinder the recognition of injuries as a top disease burden, probably the main reason for lack of funding or underfunding by funding agencies in injury and trauma care research.
      Using data provided by the U.S. Centers for Disease Control and Prevention (CDC), we investigated the total number of deaths, age-adjusted death rates, and YPLL under the age of 70 y in individuals (YPLL-70) from 1981 to 2019. We examined trends of the top 5 leading causes of death and acquired immunodeficiency syndrome (AIDS) to support our claim that unintentional injuries, suicide, and violence should be treated as a top priority in medical research, public health programs, and federal and state funding decisions. Data with regard to U.S. health care spending by disease conditions at the national level and the NIH disease-specific research funding levels from 2021 literature
      • Ballreich J.M.
      • Gross C.P.
      • Powe N.R.
      • Anderson G.F.
      Allocation of national institutes of health funding by disease category in 2008 and 2019.
      ,
      • Rees C.A.
      • Monuteaux M.C.
      • Herdell V.
      • Fleegler E.W.
      • Bourgeois F.T.
      Correlation between national institutes of health funding for pediatric research and pediatric disease burden in the US.
      were used in our arguments that injury prevention, suicide, violence, drug overdose, and trauma care research need significantly more funding.

      Methods

      Data used in our study were from the CDC's Web-based Injury Statistics Query and Reporting System (WISQARS),
      • Ballesteros M.F.
      • Webb K.
      • McClure R.J.
      A review of CDC's web-based injury Statistics Query and reporting system (WISQARS™): planning for the future of injury surveillance.
      ,
      Centers for Disease Control and Prevention (CDC)
      Leading causes of death reports, 1981 - 2019.
      in which mortality data compiled all deaths reported in the U.S. National Vital Statistics System. Users of WISQARS range from reporters, members of the general public to those highly trained and skilled academic researchers and public health professionals. WISQARS is expected to provide the foundations for program development by researchers and public health practitioners.
      In our study, we gathered data from the top ten leading causes of death of U.S. individuals of both sexes and all races below the age of 70 y. The cut point of 70 y of age was chosen to examine the burden of diseases and their impact on the U.S. most productive or younger generations of society.
      The WISQARS allowed us to access and download 39 y of U.S. death data from 1981 to 2019. Files from each year were downloaded into a Microsoft Excel spreadsheet and reorganized into a master spreadsheet compiling total number of deaths, age-adjusted death rates, and YPLL-70 of all years. We first identified the top ten leading causes of death among individuals younger than 70 y old according to the most recent years, 2018 and 2019. We then ran multiple data queries to gather data of these ten leading causes of death for each year from 1981 to 2019. Deaths caused by AIDS were included in the study due to its sudden rise and fall of the epidemic in the late 1980s to early 1990s, which represents a unique death pattern and national funding prioritization that still have an impact on society, public health programs, and federal and state research funding until now.
      In this paper, we first presented the total number of deaths of the top ten leading causes among U.S. individuals of 70 y old or younger by year from 1981 to 2019. We then evenly divided these 39 y of the study period into three periods: period 1 (1981-1993), period 2 (1994-2006), and period 3 (2007-2019) and calculated the percent change (%) of YPLL-70 by the ten leading causes of death during each period. We aimed to identify diseases or conditions that had increased % change of YPLL-70 in comparison with those with decreased % change of YPLL-70. We reported trends of the age-adjusted death rate per 100,000 U.S. people and YPLL-70 of the top five leading causes of death by graphing them against time from 1981 to 2019. We only choose the top five leading causes of death in the graphs to highlight major mortality causes. Finally, we graphed the age-adjusted death rate per 100,000 people for top five leading causes of death in 2019 and the NIH funding for each of the top five leading causes in the same year to highlight the discrepancy of the injury burden and the federal funding level.

      Results

      The total number of deaths and the yearly trend of the top ten leading causes of death are presented in the Supplemental Table in Data in Brief. The total number of deaths caused by malignant neoplasms in 2019 was 244,994, followed by 183,442 deaths of heart diseases, 121,476 deaths of unintentional injuries, and 41,051 suicide deaths. The total number of deaths caused by unintentional injuries, suicide, and homicide in 2019 was 180,989. Back in 1981, the total number of deaths caused by malignant neoplasm was 221,878, 246,628 deaths by heart diseases, 81,038 deaths by unintentional injuries, and 24,485 deaths by suicide. Deaths caused by diabetes increased from 13,984 in 1981 to 36,157 in 2019. A total of 13,298 deaths caused by AIDS were first shown in 1987, peaked at 42,805 deaths in 1995, and dropped to 4512 deaths in 2019.
      Table shows the percent (%) change of YPLL-70 in the United States by the ten leading causes of death during three periods of 1981-1993, 1994-2006, and 2007-2019. YPLL-70 caused by perinatal diseases, congenital anomalies, and cerebrovascular diseases dropped in each of these three periods, where perinatal disease deaths had a 30.24% drop during 1981-1993, 0.30% drop during 1994-2006, and 28.70% drop during 2007-2019. YPLL-70 caused by congenital anomalies had a 17.87% drop during 1981-1993, 13.80% drop during 1994-2006, and 20.28% drop during 2007-2019. In comparison, YPLL-70 caused by unintentional injuries had a 22.20% drop during 1981-1993 but 19.38% increase during 1994-2006 and 18.59% increase during 2007-2019. YPLL-70 caused by suicide had a 7.40% increase during 1981-1993, 1.22% drop during 1994-2006, but a significant 34.16% increase during 2007-2019. YPLL-70 caused by diabetes had a 43.08% increase during 1981-1993, 35.55% increase during 1994-2006, and 24.65% increase during 2007-2019. Diabetes was the only disease among the top ten leading causes of death that caused a significant increase in YPLL-70 during each of the three periods we examined.
      TablePercentage (%) change of years of potential life lost before the age of 70 y (YPLL-70) in the United States by ten leading causes of deaths, 1981-2019.
      Cause of deathPeriod 1 (1981-1993)Period 2 (1994-2006)Period 3 (2007-2019)
      YPLL-70 in 1981YPLL-70 in 1993% changeYPLL-70 in 1994YPLL-70 in 2006% changeYPLL-70 in 2007YPLL-70 in 2019% change
      Unintentional injury3,041,8402,366,491−22.20%2,362,4472,820,32219.38%2,811,1453,333,85718.59%
      Suicide769,830826,8337.40%841,304831,033−1.22%853,2811,144,79134.16%
      Homicide852,7841,007,87818.19%966,478701,240−27.44%693,779681,269−1.80%
      Malignant neoplasm2,760,2312,846,0683.11%2,851,8302,925,3912.58%2,918,6212,629,777−9.90%
      Heart disease2,687,1772,205,966−17.91%2,198,2392,138,276−2.73%2,112,6142,108,654−0.19%
      Perinatal disease1,512,4401,055,086−30.24%1,012,5431,009,486−0.30%1,020,011727,292−28.70%
      Liver disease382,048307,891−19.41%311,377329,6415.87%351,718476,54935.49%
      Congenital anomalies798,526655,854−17.87%627,209540,636−13.80%539,602430,156−20.28%
      Diabetes mellitus170,481243,91743.08%256,848348,16035.55%341,930426,13124.63%
      Cerebrovascular disease425,245363,060−14.62%371,154369,902−0.34%365,278356,858−2.31%
      The top ten leading causes of deaths were determined using 2018-19 death data.
      The age-adjusted death rate trend for the top 5 leading causes and AIDS among U.S. individuals who were 70 y of age or younger is shown in Figure 1. Malignant neoplasms, heart diseases, and perinatal diseases all had a consistent drop in age-adjusted death rates during the 39 y from 1981 to 2019. On the other hand, the age-adjusted rate of unintentional injuries fluctuated during the study period but increased significantly after 2015. Suicide age-adjusted death rates also increased in recent years.
      Figure thumbnail gr1
      Fig. 1The age-adjusted death rate per 100,000 people for the top five leading causes of death and AIDS in U.S. individuals younger than 70 y from 1981 to 2019. Note: The top five leading causes of deaths were based on 2018-2019 U.S. death data. The age-adjusted death rate for total injuries was taken directly from WISQARS and included unintentional injury, suicide, homicide, and other injuries.
      The YPLL-70 trend is reported in Figure 2. Unintentional injuries caused 3,333,857 YPLL-70 in 2019 and were the only condition that had an increase of more than 300,000 YPLL-70. Suicide only had a slight increase. Malignant neoplasms stayed relatively the same, with an approximate decrease of 100,000 YPLL-70 from 1981 to 2019. In comparison, perinatal diseases showed a substantial decrease of almost 800,000 YPLL-70.
      Figure thumbnail gr2
      Fig. 2YPLL for the top five leading causes of death and AIDS in U.S. individuals younger than 70 y from 1981 to 2019. Note: The top five leading causes of death were based on 2018-2019 U.S. death data. When YPLL was calculated for total injuries, only unintentional injury, suicide, and homicide were included in the total injury category.
      Deaths caused by AIDS had a very interesting trend pattern from 1981 to 2019. Deaths caused by AIDS were first captured in the U.S. death data system in 1987 with a total number of 13,298 deaths, which was among the top ten leading causes of death in 1987. After that, deaths caused by AIDS had increased and peaked in 1995. Two years after, deaths caused by AIDS had shown a rather rapid decline until 1997, while it continued to gradually decrease and fall out of the top ten leading causes of death in 2005. Under 5000 deaths in U.S. individuals under 70 y of age were caused by AIDS each year in 2018 and 2019.
      Figure 3 shows the age-adjusted rate per 100,000 people for the top five leading causes of deaths and human immunodeficiency virus (HIV)/AIDS in 2019 and the NIH funding level for each of the leading death causes in the same year. The age-adjusted death rate for unintentional injuries was 1182 per 100,000 people in 2019, and the NIH funding in the same year was $897 million. In comparison, the age-adjusted death rate for cancer, heart disease, and HIV/AIDs was 786, 649, and 30 per 100,000 people while the NIH funding was $2,560, $2,394, and $3037 million, respectively.
      Figure thumbnail gr3
      Fig. 3The age-adjusted death rate per 100,000 people and NIH annual spending (in $ millions) in 2008 versus 2019.

      Discussion

      Examining the burden of disease trend provides evidence about the top burden of diseases in the United States over time and could shed lights on potential priorities of public health interventions and research funding in the coming years. This study analyzed a 39-y trend of total number of deaths, age-adjusted rates, and YPLL among U.S. individuals who were 70 y of age or younger. Results of this study suggest an overall decreasing trend in the age-adjusted death rates between 1981 and 2019 for malignant neoplasms, heart diseases, perinatal diseases, and HIV/AIDS. YPLL-70 dropped significantly for perinatal diseases and congenital anomalies as well as modestly for malignant neoplasms, heart diseases, and cerebrovascular diseases. In contrast, both age-adjusted death rates and YPLL-70 for unintentional injuries and suicide increased significantly during the 13-y period from 2007 to 2019, particularly after 2013. YPLL-70 for liver disease and diabetes also had a large increase in the past decade. The 2019 NIH funding disproportionally underfunded injury and trauma research.
      Ma et al. examined the temporal trends of mortality in the United States from 1969 to 2013 and reported an overall decreasing trend in the age-adjusted death rate for all causes combined, heart diseases, cancer, stroke, unintentional injuries, and diabetes.
      • Ma J.
      • Ward E.M.
      • Siegel R.L.
      • Jemal A.
      Temporal trends in mortality in the United States, 1969-2013.
      Woolf et al. studied U.S. life expectancy and mortality rate from 1959 to 2017 and reported that life expectancy increased during the past 60 y, but the rate of increase slowed in the past decade.
      • Woolf S.H.
      • Schoomaker H.
      Life expectancy and mortality rates in the United States, 1959-2017.
      An alarming decrease in U.S. life expectancy after 2014 was observed, and a major contributor was reported to be an increase in mortality from drug overdose and suicide among adolescents and young adults.
      • Woolf S.H.
      • Schoomaker H.
      Life expectancy and mortality rates in the United States, 1959-2017.
      We found age-adjusted death rates caused by unintentional injuries and suicide increased significantly after 2015, which is consistent with Woolf et al.’s conclusion that injuries had a relatively heavy toll on U.S. life expectancy in recent years. The three waves of rapid rise of opioid pain medication and illicit drug overdose deaths, started around year 2000 but continuing as of 2022, are considered the major underlying cause of the significantly increased unintentional injury burden in the United States.
      Centers for Disease Control and Prevention (CDC)
      Three waves of opioid overdose deaths.
      According to the Injury Facts published by the National Safety Council, deaths caused by an opioid overdose have surpassed motor vehicle crash deaths in 2017.
      YPLL is a public health measure that assesses the impact of deaths occurring in years preceding a conventional cutoff year of age to better represent the burden of premature death.
      Centers for Disease Control and Prevention (CDC)
      Years of potential life lost before age 65--United States, 1990 and 1991.
      ,
      Centers for Disease Control and Prevention (CDC)
      Firearm-related years of potential life lost before age 65 years--United States, 1980-1991.
      The CDC examined YPLL-65 from 1990 to 1991 and firearm-related YPLL-65 from 1980-1991.
      Centers for Disease Control and Prevention (CDC)
      Years of potential life lost before age 65--United States, 1990 and 1991.
      ,
      Centers for Disease Control and Prevention (CDC)
      Firearm-related years of potential life lost before age 65 years--United States, 1980-1991.
      Unintentional injuries were found to account for the largest proportion of YPLL-65 from all causes (17.5%), followed by malignant neoplasms (15.1%), suicide/homicide (12.2%), heart diseases (11.2%), congenital anomalies (5.5%), and AIDS (5.4%) during 1990-1991.
      Centers for Disease Control and Prevention (CDC)
      Years of potential life lost before age 65--United States, 1990 and 1991.
      Our study used YPLL-70 that focuses on people before retirement and also found that unintentional injuries accounted for the largest proportion of YPLL-70 from all causes (20.6%), followed by malignant neoplasms (16.5%), heart diseases (13.2%), and suicide/homicide (11.4%). The combined unintentional injuries, suicide, and homicide accounted for 32.0% of YPLL-70 from all causes in the United States. The total number of U.S. deaths caused by unintentional injury, suicide, and homicide in 2019 was 180, 989, very close to the total number of death (183,442) caused by heart diseases. A recent study by Dieleman et al.
      • Dieleman J.L.
      • Cao J.
      • Chapin A.
      • et al.
      US health care spending by payer and health condition, 1996-2016.
      estimated U.S. spending on health care by aggregated health categories and reported a total of $231.1 billion in 2016 on treating injuries. In comparison, U.S. health care spent $389.9 billion on musculoskeletal disorders, $309.1 billion on diabetes, urogenital, blood, and endocrine diseases, and $255.1 billion on cardiovascular diseases in the same year.
      • Dieleman J.L.
      • Cao J.
      • Chapin A.
      • et al.
      US health care spending by payer and health condition, 1996-2016.
      Despite injuries (unintentional injuries, suicide, and homicide) being among the leading causes of death in terms of age-adjusted death rate, YPLL, and health care spending, research and program priorities shown by federal funding such as the NIH do not adequately reflect this reality. In fact, unintentional injuries, suicide, and violence are considered consistently underfunded based on allocated funding from the NIH.
      • Dowd B.
      • McKenney M.
      • Boneva D.
      • Elkbuli A.
      Disparities in National Institute of Health trauma research funding: the search for sufficient funding opportunities.
      ,
      • Glass N.E.
      • Riccardi J.
      • Farber N.I.
      • Bonne S.L.
      • Livingston D.H.
      Disproportionally low funding for trauma research by the national institutes of health: a call for a national institute of trauma.
      Our study confirmed that injury research is still underfunded by the U.S. premier funding agency. Studies published in 1999,
      • Gross C.P.
      • Anderson G.F.
      • Powe N.R.
      The relation between funding by the National Institutes of Health and the burden of disease.
      2011,
      • Gillum L.A.
      • Gouveia C.
      • Dorsey E.R.
      • et al.
      NIH disease funding levels and burden of disease.
      and 2021
      • Ballreich J.M.
      • Gross C.P.
      • Powe N.R.
      • Anderson G.F.
      Allocation of national institutes of health funding by disease category in 2008 and 2019.
      examined the relationship between NIH disease funding levels and burden of disease. Similar conclusions regarding NIH funding toward injuries were reached in all these studies. Although total injuries, including unintentional injuries, suicide, and homicide, accounted for the highest proportion of YPLL from all causes and the total number of injury-related deaths was close to the total number of death caused by heart diseases in 2019, the proportion of NIH total funding toward injuries was less than 2%, which was significantly lower than 6.5% of NIH total funding toward cancer and 6.1% toward cardiovascular diseases.
      • Ballreich J.M.
      • Gross C.P.
      • Powe N.R.
      • Anderson G.F.
      Allocation of national institutes of health funding by disease category in 2008 and 2019.
      Although the total number of deaths caused by HIV/AIDS dropped to less than 5000 starting in 2018, the proportion of NIH total funding toward HIV/AIDS was still 7.7% of its total research grants and a total of $3037 million in 2019.
      • Ballreich J.M.
      • Gross C.P.
      • Powe N.R.
      • Anderson G.F.
      Allocation of national institutes of health funding by disease category in 2008 and 2019.
      In 2020 and 2021, COVID-19 has ravaged the world as a global pandemic, infecting over 200 million individuals and even killing over 4.5 million individuals. In response, government agencies and societies around the world shifted priorities in order to combat this pandemic. It should be noted that due to the shift in priorities in both research and public awareness, medical research in fighting COVID-19 pandemic made major achievements. In fact, researchers took approximately 1 y to produce the first COVID-19 vaccine, a process that can usually take over a decade. A similar phenomenon could be observed during the late 1980s to early 1990s; when the HIV/AIDS epidemic became rampant, government funding agencies prioritized research and intervention programs to target HIV/AIDS. Our study suggests that HIV/AIDS climbed from 1987 and peaked in 1995, before sharply decreasing and falling out of the top ten burdens of disease. Even with such a major achievement in fighting against HIV/AIDS in the past 30 y, it is arguable whether the current significant high proportion of NIH research funding toward HIV/AIDS is still justifiable given the changing landscape of the top leading causes of death in the United States where injury, heart disease, and malignant neoplasm have the top three largest YPLL-70.
      It is possible that major achievements could also happen to injury prevention and trauma care research if more awareness is raised toward unintentional injuries, suicide, and homicide. More importantly, federal funding toward injuries should increase significantly to match the burden caused by injuries in society. The mismatch between the burden of injuries and lack of adequate injury prevention and trauma care research funding has long been recognized by leading federal agencies. Despite the recognition of lack of sufficient funding in 1966 and in 1985 by the National Research Council,
      National Research Council
      Accidental Death and Disability: The Neglected Disease of Modern Society.
      ,
      National Research Council
      Injury in America: A Continuing Public Health Problem.
      in 1999 by the Institute of Medicine,
      Institute of Medicine (IOM)
      Reducing the burden of injury: advancing prevention and treatment.
      and in 2016 by the National Academies of Sciences, Engineering, and Medicine,
      Institute of Medicine (IOM)
      Reducing the burden of injury: advancing prevention and treatment.
      ,
      National Academies of Sciences, Engineering, Medicine
      A National Trauma Care System: Integrating Military and Civilian Trauma Systems to Achieve Zero Preventable Deaths After Injury.
      the NIH funding allocated toward injury prevention and trauma care research is pitiful. Furthermore, the distribution of NIH research awards spans nearly every NIH institute, center, and office. Lack of a dedicated trauma institute is argued as a major hurdle for researchers in injury prevention and trauma care to successfully raise awareness of injuries as a top priority among the general public and funding decision makers. An increase in dedicated funding toward injury prevention and trauma care research and the establishment of a national institute or center have been recommended by the National Academies of Sciences, Engineering, and Medicine's recent report.
      National Academies of Sciences, Engineering, Medicine
      A National Trauma Care System: Integrating Military and Civilian Trauma Systems to Achieve Zero Preventable Deaths After Injury.
      Our study provides evidence that establishing a national institute or center should be a national priority. It is hoped that such a dedicated national institute on injury prevention and trauma care research could gather the resources and attract a cadre of talented researchers to prevent premature deaths caused by injuries and to improve trauma care and patient outcomes in the United States and around the world.
      • Glass N.E.
      • Riccardi J.
      • Farber N.I.
      • Bonne S.L.
      • Livingston D.H.
      Disproportionally low funding for trauma research by the national institutes of health: a call for a national institute of trauma.
      The findings of this study are subject to a few limitations. First, the method used to calculate YPLL was based on the assumption that deaths occurred uniformly within age groups. The 70 y of age cut point used in this study may differ slightly from previously published studies that used a different age cut point.
      Centers for Disease Control and Prevention (CDC)
      Years of potential life lost before age 65--United States, 1990 and 1991.
      ,
      Centers for Disease Control and Prevention (CDC)
      Firearm-related years of potential life lost before age 65 years--United States, 1980-1991.
      ,
      • Bui A.L.
      • Coates M.M.
      • Matthay E.C.
      Years of life lost due to encounters with law enforcement in the USA, 2015-2016.
      However, it appears that these differences do not affect the relative ranking of unintentional injuries, suicide, and homicide as one of the top leading causes of death in the United States. Second, we used published NIH research funding by disease categories in Figure 3 instead of conducting a comprehensive analysis of the relationship between NIH funding and the burden of diseases that was conducted in previous publications by others.
      • Ballreich J.M.
      • Gross C.P.
      • Powe N.R.
      • Anderson G.F.
      Allocation of national institutes of health funding by disease category in 2008 and 2019.
      • Gillum L.A.
      • Gouveia C.
      • Dorsey E.R.
      • et al.
      NIH disease funding levels and burden of disease.
      • Gross C.P.
      • Anderson G.F.
      • Powe N.R.
      The relation between funding by the National Institutes of Health and the burden of disease.
      We believe that these previous publications have provided statistical data detail enough for us to support discussions and conclusions. Finally, we did not conduct tests of significance using advanced statistical modeling approaches as we believe that our conclusions and arguments could be supported as well as valid using the data presented using our approaches.

      Conclusions

      U.S. death data from 1981 to 2019 clearly show that unintentional injuries, suicide, and homicide are consistently among the top leading causes of death and YPLLs before the age of 70 y. However, comparison of the age-adjusted rate and NIH funding allocation for the top five leading death causes in 2019 provides evidence that injury prevention and trauma research has been underfunded disproportionally. The call for more funding toward injury prevention and trauma research and more national concerted and dedicated efforts deserves serious discussions and an action.

      Supplementary Materials

      Author Contributions

      A.W. and H.X. contributed to study design. A.W. contributed to data collection. A.W. contributed to data analysis. A.W. and H.X. contributed to manuscript preparation and editing.

      Disclosure

      None declared.

      Funding

      Efforts by Dr Henry Xiang in this study were supported by a grant from the CDC National Center for Injury Prevention and Control (grant #: 5R49CE003074-03 ; PI: Dr Gary Smith). The funding agency had no role in design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

      References

        • Ma J.
        • Ward E.M.
        • Siegel R.L.
        • Jemal A.
        Temporal trends in mortality in the United States, 1969-2013.
        JAMA. 2015; 314: 1731-1739
        • Ballreich J.M.
        • Gross C.P.
        • Powe N.R.
        • Anderson G.F.
        Allocation of national institutes of health funding by disease category in 2008 and 2019.
        JAMA Netw Open. 2021; 4: e2034890
        • Gillum L.A.
        • Gouveia C.
        • Dorsey E.R.
        • et al.
        NIH disease funding levels and burden of disease.
        PLoS One. 2011; 6: e16837
        • Gross C.P.
        • Anderson G.F.
        • Powe N.R.
        The relation between funding by the National Institutes of Health and the burden of disease.
        N Engl J Med. 1999; 340: 1881-1887
        • Rees C.A.
        • Monuteaux M.C.
        • Herdell V.
        • Fleegler E.W.
        • Bourgeois F.T.
        Correlation between national institutes of health funding for pediatric research and pediatric disease burden in the US.
        JAMA Pediatr. 2021; 175: 1236-1243
        • Centers for Disease Control and Prevention (CDC)
        Years of potential life lost before age 65--United States, 1990 and 1991.
        Morb Mortal Wkly Rep. 1993; 42: 251-253
        • Centers for Disease Control and Prevention (CDC)
        Firearm-related years of potential life lost before age 65 years--United States, 1980-1991.
        Morb Mortal Wkly Rep. 1994; 43: 609-611
        • Dowd B.
        • McKenney M.
        • Boneva D.
        • Elkbuli A.
        Disparities in National Institute of Health trauma research funding: the search for sufficient funding opportunities.
        Medicine (Baltimore). 2020; 99: e19027
        • Woolf S.H.
        • Schoomaker H.
        Life expectancy and mortality rates in the United States, 1959-2017.
        JAMA. 2019; 322: 1996-2016
        • Bui A.L.
        • Coates M.M.
        • Matthay E.C.
        Years of life lost due to encounters with law enforcement in the USA, 2015-2016.
        J Epidemiol Community Health. 2018; 72: 715-718
        • Arcà M.
        • di Orio F.
        • Forastiere F.
        • Tasco C.
        • Perucci C.A.
        Years of potential life lost (YPLL) before age 65 in Italy.
        Am J Public Health. 1988; 78: 1202-1205
        • Borse N.N.
        • Rudd R.A.
        • Dellinger A.M.
        • Sleet D.A.
        Years of potential life lost from unintentional child and adolescent injuries--United States, 2000-2009.
        J Safety Res. 2013; 45: 127-131
        • Rumisha S.F.
        • George J.
        • Bwana V.M.
        • Mboera L.E.G.
        Years of potential life lost and productivity costs due to premature mortality from six priority diseases in Tanzania, 2006-2015.
        PLoS One. 2020; 15: e0234300
        • Paciej-Gołębiowska P.
        • Pikala M.
        • Maniecka-Bryła I.
        Years of life lost due to diseases of the digestive system in Poland in 2000-2014.
        J Gastrointestin Liver Dis. 2018; 27: 419-425
        • Glass N.E.
        • Riccardi J.
        • Farber N.I.
        • Bonne S.L.
        • Livingston D.H.
        Disproportionally low funding for trauma research by the national institutes of health: a call for a national institute of trauma.
        J Trauma Acute Care Surg. 2020; 88: 25-32
        • Ballesteros M.F.
        • Webb K.
        • McClure R.J.
        A review of CDC's web-based injury Statistics Query and reporting system (WISQARS™): planning for the future of injury surveillance.
        J Safety Res. 2017; 61: 211-215
        • Centers for Disease Control and Prevention (CDC)
        Leading causes of death reports, 1981 - 2019.
        (Available at:)
        https://webappa.cdc.gov/sasweb/ncipc/leadcause.html
        Date: 2021
        Date accessed: August 15, 2021
        • Centers for Disease Control and Prevention (CDC)
        Three waves of opioid overdose deaths.
        (Available at:)
        • National Safety Council
        Injury facts.
        (Available at:)
        • Dieleman J.L.
        • Cao J.
        • Chapin A.
        • et al.
        US health care spending by payer and health condition, 1996-2016.
        JAMA. 2020; 323: 863-884
        • National Research Council
        Accidental Death and Disability: The Neglected Disease of Modern Society.
        The National Academies Press, Washington, DC1966
        • National Research Council
        Injury in America: A Continuing Public Health Problem.
        The National Academies Press., Washington, DC1985
        • Institute of Medicine (IOM)
        Reducing the burden of injury: advancing prevention and treatment.
        in: Bonnie R.J. Fulco C.E. Liverman C.T. Reducing the Burden of Injury: Advancing Prevention and Treatment. The National Academies Press, Washington DC1999
        • National Academies of Sciences, Engineering, Medicine
        A National Trauma Care System: Integrating Military and Civilian Trauma Systems to Achieve Zero Preventable Deaths After Injury.
        The National Academies Press, Washington, DC2016