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Do People With HIV Have to Exercise
Harder to Get Same Muscle Benefit?
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10th International Workshop on HIV and Aging, October 10-11, 2019, New York
Mark Mascolini
Supervised cardiovascular and resistance exercise significantly improved lean mass in older HIV-negative people but not in older people with HIV in a 55-person comparison at the University of Colorado [1]. Greater comorbidity in the HIV group did not explain the difference. Total body fat dropped significantly in both groups.
Older people with HIV face age-related sarcopenia (skeletal muscle loss) and fat gains. Previous work by University of Colorado researchers found similar exercise-induced improvements in physical function (VO2 max, stair climb, and 400-meter walk time) among older HIV-positive and negative people [2].
The new analysis compared exercise-related changes in muscle and fat in sedentary 50- to 75-year-olds with or without HIV. The University of Colorado team used DXA scans to compare four body measures before and after exercise: total body lean mass (an indicator of muscle mass), appendicular lean mass adjusted for height, total body fat mass, and visceral fat area. Everyone with HIV had taken combination antiretroviral therapy for more than 2 years, had an undetectable viral load for more than 2 years, and had a CD4 count above 200.
Participants completed a 24-week supervised moderate- to high-intensity cardiovascular and resistance exercise program. Diet was not part of the program, which had 3 sessions per week. To identify predictors of muscle and fat change, the researchers used multivariable regression analysis adjusted for age or for exercise adherence and comorbidities measured by the Veterans Aging Cohort (VACS) Risk Index.
Most of the 27 people with HIV and the 28 without HIV were men (93%), white (80%), and non-Hispanic (86%). Median age was nonsignificantly younger in the HIV group (56 and 60). More people with HIV used testosterone (20% versus 8%), but similar proportions used statins (about 45% overall). Comorbidities were more frequent in the HIV group, as indicated by a significantly higher proportion with a VACS Index above 20 (59% versus 25%, P = 0.02). People with HIV had been diagnosed with the infection for a median of 23 years, had taken antiretrovirals for 17 years, and had a median CD4 count of 546. Everyone with HIV had a viral load below 50 copies.
Before the exercise program began, people with HIV had a lower body mass index (26.9 versus 29.6 kg/m2, P = 0.019) and less total fat mass than the HIV-negative group (20.6 versus 27.2 kg, P = 0.003). The two groups were similar in visceral fat area (184 and 211 cm2), total body lean mass (57.7 and 60.0 kg), and appendicular lean mass adjusted for height (8.6 and 8.9 kg/m2).
When the exercise program ended, HIV-negative participants had a significant gain in lean mass (0.8 kg, 0.0 to 1.6, P < 0.05), but the lean mass gain in people with HIV was not significant (0.6 kg, -0.2 to 1.4, P = 0.12). HIV-positive and negative participants had similar (nearly significant) gains in appendicular lean mass (0.14 and 0.15 kg/m2, P = 0.06), while total body fat fell significantly in both groups (-2.0 kg with HIV, P < 0.01; -0.9 kg without HIV, P < 0.05), as did visceral fat area (-17.7 cm2 with HIV, P < 0.01; -10.3 cm2 without HIV, P < 0.05). Exercise adherence was a significant predictor of drops in total fat mass and visceral fat area. More frequent comorbidity in the HIV group did not explain their lower gain in lean mass.
The researchers suggested that older people with HIV "may need more resistance exercise [than HIV-negative people] to stimulate muscle hypertrophy and increase lean mass." The earlier study found that HIV-positive people randomized to high-intensity versus moderate-intensity exercise gained significantly more strength in the bench press and leg press [2].
References
1. Jankowski C, Wilson M, Brown T, MaWhinney S, Erlandson K. Blunted increase in muscle mass after exercise training in people aging with HIV. 10th International Workshop on HIV and Aging, October 10-11, 2019, New York. Abstract 1.
2. Erlandson KM, MaWhinney S, Wilson M, et al. Physical function improvements with moderate or high-intensity exercise among older adults with or without HIV infection. AIDS. 2018;32:2317-2326. https://www.ncbi.nlm.nih.gov/pubmed/30134299
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