@article {Bakerjrheum.150280, author = {Joshua F. Baker and Joan Marie Von Feldt and Sogol Mostoufi-Moab and Woojin Kim and Elena Taratuta and Mary B. Leonard}, title = {Insulin-like Growth Factor 1 and Adiponectin and Associations with Muscle Deficits, Disease Characteristics, and Treatments in Rheumatoid Arthritis}, elocation-id = {jrheum.150280}, year = {2015}, doi = {10.3899/jrheum.150280}, publisher = {The Journal of Rheumatology}, abstract = {Objective Rheumatoid arthritis (RA) is associated with low muscle mass and density. The objective of our study was to evaluate associations between 2 serum biomarkers [insulin-like growth factor 1 (IGF-1) and adiponectin] and skeletal muscle in RA. Methods Whole-body dual energy X-ray absorptiometry measures of the appendicular lean mass index (ALMI; kg/m2) and total fat mass index (kg/m2), as well as the peripheral quantitative computed tomography measures of the lower leg muscle and fat cross-sectional area (CSA; cm2) and muscle density (an index of fat infiltration) were obtained from 50 participants with RA, ages 18{\textendash}70 years. Multivariable linear regression analyses evaluated associations between body composition and levels of adiponectin and IGF-1, adjusted for age, sex, and adiposity. Results Greater age was associated with higher adiponectin (p = 0.06) and lower IGF-1 (p = 0.004). Eight subjects had IGF-1 levels below the reference range for their age and sex. These subjects had significantly lower ALMI and muscle CSA in multivariable models. Lower IGF-1 levels were associated with greater clinical disease activity and severity, as well as low ALMI, muscle CSA, and muscle density (defined as 1 SD below normative mean). After adjusting for age and sex, greater adiponectin levels were associated with lower BMI (p = 0.02) as well as lower ALMI, and lower muscle CSA, independent of adiposity (p \< 0.05). Only greater Health Assessment Questionnaire scores were significantly associated with lower adiponectin levels. Conclusion Low IGF-1 and greater adiponectin levels are associated with lower muscle mass in RA. Lower IGF-1 levels were seen in subjects with greater disease activity and severity.}, issn = {0315-162X}, URL = {https://www.jrheum.org/content/early/2015/08/26/jrheum.150280}, eprint = {https://www.jrheum.org/content/early/2015/08/26/jrheum.150280.full.pdf}, journal = {The Journal of Rheumatology} }