title: Reduced aerobic capacity and physical functioning in older HIV-infected men.
abstract: Aerobic capacity and physical functioning decline with age and chronic illness. The extent of physical disability is unknown in older HIV-infected adults, who represent a rapidly growing proportion of HIV/AIDS patients in the United States. We performed functional performance testing including treadmill testing in 32 HIV-infected male veterans aged 40-69 years. Controls were 47 healthy male subjects tested previously in the same exercise laboratory. HIV-infected subjects were classified as younger (40-49 years, n = 12) or older age (50+ years, n = 20). Peak aerobic capacity (VO2peak) was significantly reduced in the older vs. younger HIV subjects [19.1 mL/kg/min +/- 5.7 (mean, SD) vs. 25.2 +/- 4.2, p = 0.01]. VO2peak was reduced 41% +/- 15% (mean, SD) in HIV-infected subjects compared to expected values from age-matched healthy controls. Regression analyses show a similar decline in VO2peak with age in HIV-infected and healthy controls. Mean 6-min walk distance was not significantly different between the HIV-infected age groups, and was reduced only 8% compared to expected values for healthy adults. Current CD4 count and HAART exposure were similar in the two age groups and were not significantly associated with VO2peak. Anemia (HCT <35%) was significantly associated with reduced VO2peak (p = 0.02), but this association was not independent of the effect of age (p = 0.1). We conclude that older HIV-infected adults have markedly impaired aerobic capacity but maintain the capacity to undertake day-to-day activities. Additional physiologic and metabolic testing is needed to measure the effect of HAART toxicity and primary aging on aerobic capacity, and to determine if older HIV-infected adults are at greater risk.
authors.affiliation: University of Maryland School of Medicine, and the Baltimore Veterans Administration Medical Center, Geriatric Research, Education and Clinical Center, Baltimore, Maryland 21201, USA. Oursler@umbi.umd.edu
authors.forename: K K
authors.initials: KK
authors.lastname: Oursler
authors.forename: J D
authors.initials: JD
authors.lastname: Sorkin
authors.forename: B A
authors.initials: BA
authors.lastname: Smith
authors.forename: L I
authors.initials: LI
authors.lastname: Katzel
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D015444:Exercise / Q000502:physiology*; D015658:HIV Infections; D006801:Humans; D008297:Male; D008875:Middle Aged; D010809:Physical Fitness / Q000502:physiology