An update on the impact of HIV/AIDS on life expectancy in the United States

We used the potential gains in life expectancy to quantify the impact of eliminating HIV/AIDS, heart disease and malignant neoplasms on the life expectancy of the population of the USA from 1987 to 1999 by race and sex groups. We previously reported the results from 1987 to 1992, with a focus on the year 1992. This report gives an update to 1999, showing the impact of improvements in the care and treatment of HIV/AIDS in recent years. Life expectancy at birth is a hypothetical average longevity for a newborn if the current age-specific mortality remains the same. Life expectancy in various forms has been a widely used health indicator for health professionals and the general public [1–6]. People live in an environment of competing risks and may die as a result of any risk (disease) [7,8]. Measuring the impact of deaths from various diseases on life expectancy provides valuable information for the general public. The measurement is important for researchers and policy makers in evaluating the effect of interventions and allocating resources. Under competing risks the potential gains in life expectancy (PGLE) is an effective indicator for measuring the impact of various causes of death on society [9,10]. In the literature, there are two other widely used classes of indicators for a similar purpose. The disability adjusted life years are used by the World Health Organization, and the potential years of life lost are used in the Healthy People 2010 report [11,12]. These two classes of indicators do not properly take into account the competing risks of death [8]. In a previous study, we used PGLE to measure the impact of HIV/AIDS on the life expectancy of the US population from 1987 to 1992 [13]. Because of more recent advances in the care and treatment of HIV/AIDS, this report gives an update to 1999. The age-specific mortality rates of the USA as a result of HIV/AIDS [International Classification of Diseases (ICD) version 9: 042–044; ICD-10: B20–B24], diseases of the heart (ICD-9: 309–398, 402, 404, 410-429; ICD-10: I00–I09, I11, I13, I20–I51) and malignant neoplasms (ICD-9: 140–208; ICD-I0: C00–C97) were available from the National Center for Health Statistics [14–16]. The mortality data before 1999 were classified according to ICD-9 [14]. From 1999, the mortality data have been tabulated according to ICD-l0 [15]. The mortality data for HIV/AIDS have been published since 1987. The method of computing PGLE is available in our previous report [13]. From our computation, the life expectancies in years of the US total, male and female population increased from 74.94, 71.35 and 78.45 in 1987 to 76.69, 73.97 and 79.30 in 1999, respectively. For the US white total, white male and white female populations, the life expectancies were 75.61, 72.12 and 79.02 in 1987 and 77.26, 74.63 and 79.80 in 1999; whereas for the black total, black male and black female populations, the life expectancies were 69.22, 64.66 and 73.69 in 1987 and 71.50, 67.90 and 74.84 in 1999. 1987 was the first year that the age-specific mortality rates as a result of HIV/AIDS were available for the US population. The potential gains in life expectancies for the US population at birth by the complete elimination of HIV/AIDS, diseases of the heart and malignant neoplasms were 0.14, 3.71 and 3.06, respectively. In 1995, the impact of the deaths from HIV/AIDS on life expectancy in terms of the potential gains in life expectancy increased from 0.14 in 1987 and achieved its highest value of 0.41 in 1995. It is well known that HIV/AIDS has a greater effect on individuals of working age (15–64 years), whereas diseases of the heart and malignant neoplasms have a greater impact on individuals after the age of 65 years. To measure the impact of these diseases on life expectancy in the working age group, we constructed the partial life table, and computed the potential gains in life expectancy during the working ages. For the total population in the working age group, completely eliminating deaths from HIV/AIDS, diseases of the heart and malignant neoplasms would result in potential gains in life expectancy of 0.09, 0.48 and 0.57 in 1987, 0.24, 0.40 and 0.52 in 1995, 0.07, and 0.36 and 0.48 in 1999. For the white population, these values were 0.07, 0.44 and 0.55 in 1987, 0.18, 0.36, 0.50 in 1995 and 0.04,0.22 and 0.47 in 1999. For the black population, the values were 0.21, 0.80 and 0.75 in 1987, 0.73, 0.69 and 0.67 in 1995, 0.30, and 0.64 and 0.63 in 1999, respectively. Table 1 summarizes these potential gains in life expectancy.Table 1: Potential gains in life expectancy (in years) by the complete elimination of HIV/AIDS, disease of the heart and malignant neoplasms for the population of the United States in 1987, 1995 and 1999.From Fig. 1, we can see that the potential gains in life expectancy as a result of HIV/AIDS for the black female population were lower than those of white men from 1987 to 1993. After 1994, the potential gains in life expectancy for black women have been higher than those of white men. The potential gains in life expectancy for black men remained the highest among these four race and sex groups, although there was a rapid decrease after 1995. In our study, partial elimination of deaths from HIV/AIDS, diseases of the heart and malignant neoplasms were also computed. The results are not presented in this short report. Our study showed there has been great progress in reducing deaths from HIV/AIDS for the US population since 1995 in terms of potential gains in life expectancy. The progress in preventing HIV infection and reducing deaths as a result of HIV/AIDS in developing countries has been slow [17]. The effect of HIV/AIDS in the most populous countries such as China and India has grown rapidly in recent years [17]. Because of the lack of comprehensive mortality data in most developing countries, a reliable estimate of the impact of HIV/AIDS and other diseases on life expectancy for the developing countries has yet to be determined.Fig. 1. Potential gains in life expectancy (in years) for white male, white female, black male and black female populations in working ages of the United States by elimination of deaths from HIV/AIDS (1987–1999).Acknowledgements The authors would like to thank Dr Robert Anderson at the National Center for Health Statistics, US Department of Health and Human Services, for providing the link to the age–race–sex-specific mortality rates.