title: Sex and race/ethnic disparities in the cross-sectional association between depressive symptoms and muscle mass: the Multi-ethnic Study of Atherosclerosis.
abstract: BACKGROUND
  The cross-sectional area of total muscle mass has been reported to decrease by about 40% for those 20-60 years of age. Depressive symptoms may discourage motivation to engage in physical activity such as strength training shown to negate muscle loss. Inflammation related to depressive symptoms may also contribute to muscle atrophy. Physiological differences by sex and race/ethnicity may also modify the association between depression and muscle mass. Evidence on the relationship between depression (or depressive symptoms) and adiposity has been mounting; however, little is known about the depressive symptoms-muscle mass association. We sought to determine the association between elevated depressive symptoms (EDS) and lean muscle mass and whether this varies by sex and race/ethnicity.
  
  
  METHODS
  Evaluating 1605 adults (45-84 years of age) from the Multi-ethnic Study of Atherosclerosis Abdominal Body Composition, Inflammation and Cardiovascular Disease Study, we examined the cross-sectional association between EDS (Center for Epidemiologic Studies for Depression Scale score≥16 and/or antidepressant use) and computed tomography-measured abdominal lean muscle mass using linear regression. Muscles were evaluated as a whole and by functionality (locomotion vs. stabilization/posture). Covariates included height, body mass index, sociodemographics, comorbidities, inflammatory markers and health behaviors (pack-years of smoking, alcohol locomotion compared to men, total intentional exercise, daily caloric intake). Sex and race/ethnicity were assessed as potential modifiers. Statistical significance was at a p<0.05 for main effects and <0.20 for interaction.
  
  
  RESULTS
  Men with elevated depressive symptoms had 5.9 cm2 lower lean muscle mass for locomotion compared to men without EDS, fully-adjusted (CI=-10.5, -1.4, p=0.011). This was statistically significantly different from the null finding among women (interaction p=0.05). Chinese participants with EDS had 10.2 cm2 lower abdominal lean muscle mass for locomotion compared to those without EDS (fully-adjusted, CI=-18.3, -2.1, p=0.014), which was significantly different from the null relationship among White participants (interaction p=0.04). No association was observed between elevated depressive symptoms and muscle for stabilization/posture evaluating the whole population or stratified by sex or race/ethnicity.
  
  
  CONCLUSIONS
  In the presence of elevated depressive symptoms, men and Chinese participants may have lower muscle mass, particularly for locomotion.
authors.affiliation: Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe Street, Baltimore, MD, 21205, USA. rremigiobaker@gmail.com.
authors.forename: Rosemay A
authors.initials: RA
authors.lastname: Remigio-Baker
authors.affiliation: Department of Family Medicine and Public Health, University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA. mallison@ucsd.edu.
authors.forename: Matthew A
authors.initials: MA
authors.lastname: Allison
authors.affiliation: Division of Epidemiology and Community Health, University of Minnesota School of Public Health, 1300 S. 2nd Street, Minneapolis, MN, 55454, USA. schre012@umn.edu.
authors.forename: Pamela J
authors.initials: PJ
authors.lastname: Schreiner
authors.affiliation: Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, 680 N. Lake Shore Drive, Chicago, IL, 60611, USA. carnethon@northwestern.edu.
authors.forename: Mercedes R
authors.initials: MR
authors.lastname: Carnethon
authors.affiliation: Department of Nutrition and Obesity, The University of Texas School of Public Health, 1200 Pressler St, Houston, TX, 77030, USA. Jennifer.A.Nettleton@uth.tmc.edu.
authors.forename: Jennifer A
authors.initials: JA
authors.lastname: Nettleton
authors.affiliation: Department of Epidemiology, University of California, Berkeley, School of Public Health, 50 University Hall #7360, Berkeley, CA, 94720, USA. mmujahid@berkeley.edu.
authors.forename: Mahasin S
authors.initials: MS
authors.lastname: Mujahid
authors.affiliation: Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe Street, Baltimore, MD, 21205, USA. mszklo@jhu.edu.
authors.forename: Moyses
authors.initials: M
authors.lastname: Szklo
authors.affiliation: Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe Street, Baltimore, MD, 21205, USA. rcrum@jhu.edu.
authors.forename: Rosa M
authors.initials: RM
authors.lastname: Crum
authors.affiliation: Division of Psychiatry and Behavioral Sciences, Johns Hopkins School of Medicine, 5300 Alpha Commons Drive, Baltimore, MD, 21224, USA. Jeannie-marie@jhu.edu.
authors.forename: Jeannie-Marie
authors.initials: JM
authors.lastname: Leuotsakos
authors.affiliation: Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe Street, Baltimore, MD, 21205, USA. manuel.franco@uah.es.
authors.forename: Manuel
authors.initials: M
authors.lastname: Franco
authors.affiliation: Department of Family Medicine and Public Health, University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA. nicole.jensky@gmail.com.
authors.forename: Nicole
authors.initials: N
authors.lastname: Jensky
authors.affiliation: Division of Endocrinology and Metabolism, Johns Hopkins School of Medicine, 1830 E. Monument St, Suite 333, Baltimore, MD, 21287, USA. sahill@jhmi.edu.
authors.forename: Sherita Hill
authors.initials: SH
authors.lastname: Golden
mesh_terms: D050154:Adiposity; D000368:Aged; D000369:Aged, 80 and over; D001823:Body Composition; D015992:Body Mass Index; D003324:Coronary Artery Disease / Q000150:complications / Q000453:epidemiology* / Q000208:ethnology / Q000503:physiopathology; D003430:Cross-Sectional Studies; D003866:Depressive Disorder / Q000150:complications / Q000453:epidemiology* / Q000208:ethnology / Q000503:physiopathology / Q000523:psychology; D005006:Ethnicity; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D012737:Sex Factors; D014481:United States / Q000453:epidemiology