title: Age-related skeletal muscle decline is similar in HIV-infected and uninfected individuals.
abstract: BACKGROUND
  Skeletal muscle (SM) mass decreases with advanced age and with disease in HIV infection. It is unknown whether age-related muscle loss is accelerated in the current era of antiretroviral therapy and which factors might contribute to muscle loss among HIV-infected adults. We hypothesized that muscle mass would be lower and decline faster in HIV-infected adults than in similar-aged controls.
  
  
  METHODS
  Whole-body (1)H-magnetic resonance imaging was used to quantify regional and total SM in 399 HIV-infected and 204 control men and women at baseline and 5 years later. Multivariable regression identified associated factors.
  
  
  RESULTS
  At baseline and Year 5, total SM was lower in HIV-infected than control men. HIV-infected women were similar to control women at both time points. After adjusting for demographics, lifestyle factors, and total adipose tissue, HIV infection was associated with lower Year 5 SM in men and higher SM in women compared with controls. Average overall 5-year change in total SM was small and age related, but rate of change was similar in HIV-infected and control men and women. CD4 count and efavirenz use in HIV-infected participants were associated with increasing SM, whereas age and stavudine use were associated with decreasing SM.
  
  
  CONCLUSIONS
  Muscle mass was lower in HIV-infected men compared with controls, whereas HIV-infected women had slightly higher SM than control women after multivariable adjustment. We found evidence against substantially faster SM decline in HIV infected versus similar-aged controls. SM gain was associated with increasing CD4 count, whereas stavudine use may contribute to SM loss.
authors.affiliation: Department of Medicine, Washington University, St. Louis, Missouri, USA.
authors.forename: Kevin E
authors.initials: KE
authors.lastname: Yarasheski
authors.forename: Rebecca
authors.initials: R
authors.lastname: Scherzer
authors.forename: Donald P
authors.initials: DP
authors.lastname: Kotler
authors.forename: Adrian S
authors.initials: AS
authors.lastname: Dobs
authors.forename: Phyllis C
authors.initials: PC
authors.lastname: Tien
authors.forename: Cora E
authors.initials: CE
authors.lastname: Lewis
authors.forename: Richard A
authors.initials: RA
authors.lastname: Kronmal
authors.forename: Steven B
authors.initials: SB
authors.lastname: Heymsfield
authors.forename: Peter
authors.initials: P
authors.lastname: Bacchetti
authors.forename: Carl
authors.initials: C
authors.lastname: Grunfeld
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000375:Aging / Q000502:physiology*; D005260:Female; D015658:HIV Infections / Q000150:complications*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000473:pathology*; D009929:Organ Size