Despite increasing greatly in recent years, average life expectancy for people in HIV care is still about 14 years below that of their HIV-negative counterparts. However, those who have a high CD4 counts and lack other major health risk factors, including hepatitis B or C virus (HBV or HCV) coinfection, can hope to narrow this deficit considerably.

Researchers at Kaiser Permanente California conducted a study of 25,768 of their HIV-positive patients and matched them by gender, medical center and year to 257,600 of the health organization’s HIV-negative patients. The study period covered 1996 to 2011. Findings were presented at the 2016 Conference on Retroviruses and Opportunistic Infections (CROI) in Boston.

The researchers determined deaths of study participants through 2011 from electronic health records, California death certificates, and Social Security Administration data. They produced estimates of life expectancy past age 20.

A total of 2,229 HIV-positive people died during the study, as did 4,970 HIV-negative individuals, for respective mortality rates of 1,827 and 326 per 100,000 person-years. (In other words, a respective 1.827 percent and 0.326 percent of the HIV-positive and HIV-negative individuals died each year.)

For the 1996 to 2006 period, life expectancy at age 20 among the HIV-positive and HIV-negative individuals was an average of 36 and 62.3 additional years, respectively, for a gap of 26.3 years. For the 2007 to 2011 period, the life expectancy for the HIV-positive individuals increased to 48.5 additional years, shrinking the gap to 13.8 years. The lowest life expectancies among the HIV-positive individuals during the second period were among blacks (45.2 additional years) and those with a history of injection drug use (42.6 additional years).

Looking also at the 2007 to 2011 period, the researchers found that those HIV-positive people with at least 500 CD4 cells had a life expectancy of 53.8 additional years, for a gap of 8.5 years. And among the individuals with such a high CD4 count, those who were not coinfected with hep B or C had a life expectancy of 54.7 additional years, with a 6.8-year gap; those who did not abuse drugs or alcohol had a 56.2 additional-year life expectancy, with a 6.4-year gap; and non-smokers had a 55.3 additional-year life expectancy, with a 5.8-year gap.