Association between exercise and HIV disease progression in a cohort of homosexual men

PURPOSE: To study the relationship between exercise and human immunodeficie ncy virus (HIV) disease progression. METHODS: 415 individuals (156 HIV positive, 259 HIV negative), from a cohor t study of 851 homosexual men from New York City, 1985-1991. By 1991, 68 of the 156 persons developed Acquired Immune Deficiency Syndrome (AIDS) and 4 9 died with AIDS. Exercise was defined as self-report of exercising 3-4 tim es/week or daily at entry; less was considered nonexercise. CD4 lymphocyte decline was constructed for each subject by modeling log CD4 count against time in days. The association between exercise and progression to AIDS and death with AIDS, adjusting for baseline CD4 count, was determined using Cox model. Linear regression was used to model CD4 decline with exercise for H IV positive and HIV negative groups separately, adjusting for initial CD4 c ount. RESULTS: Having exercised was associated with slower progression to AIDS at 1 year (HR = 0.68, 90% confidence interval (CI): 0.4-1.17); hazard ratios (HR) at 2, 3, and 4 years were 0.96, 1.18, and 1.36, respectively. Having e xercised was also associated with slower progression to death with AIDS at 1 year (HR = 0.37, 90% CI: 0.14-0.94) with hazard ratios at 2, 3, and 4 yea rs of 0.68, 0.98, and 1.27, respectively, suggesting a protective effect cl ose to the time exercise was assessed, but an increased risk after 2 years. Exercising 3-4 times/week had a more protective effect than daily exercise . Exercisers in the HIV positive group showed an increase in CD4 count duri ng a year by a factor of 1.07. CONCLUSION: Moderate physical activity may slow HIV disease progression. (C ) 1999 Elsevier Science Inc. All rights reserved.