Longitudinal associations of serum 25-hydroxyvitamin-D Physical Activity and Knee Pain and Dysfunction with Muscle Mass Muscle Strength and Muscle Quality in Community-dwelling Older Adults — ASN Events
  1. Schedule
  2. Poster Viewing II (even numbers)
  3. Longitudinal associations of serum 25-hydroxyvitamin-D Physical Activity and Knee Pain and Dysfunction with Muscle Mass Muscle Strength and Muscle Quality in Community-dwelling Older Adults

Longitudinal associations of serum 25-hydroxyvitamin-D Physical Activity and Knee Pain and Dysfunction with Muscle Mass Muscle Strength and Muscle Quality in Community-dwelling Older Adults (#236)

Saliu Balogun 1 , Dawn Aitken 1 , Tania Winzenberg 1 , Karen Wills 1 , David Scott 2 3 , Michele Callisaya 1 2 , Graeme Jones 1
  1. Menzies Institute for Medical Research, University of Tasmania, Hobart, TASMANIA, Australia
  2. Department of Medicine, , School of Clinical Sciences at Monash Health, Faculty of Medicine, Nursing and Health Sciences, Monash University, , Clayton, Victoria, Australia
  3. Melbourne Medical School (Western Campus) and Australian Institute for Musculoskeletal Science, The University of Melbourne and Western Health,, St Albans, Victoria, Australia

Objective: Traditionally, analysis has focused on examining how loss of muscle mass, strength and muscle quality differ between individuals (between-person comparison). Less well recognised is how variability in risk factors over time within the same individual (within-person comparison) is associated with loss of muscle mass, strength and muscle quality. This study aims to describe the associations of between-person and within-person variability in serum 25-hydroxyvitamin D (25OHD), physical activity (PA) and knee pain and dysfunction with age-related loss of skeletal muscle mass, strength and muscle quality over 10 years in community-dwelling older adults.

Method: Participants (n=1033; 51% women; mean age 63±7.4 years) were measured at baseline, 2.5, 5, and 10 years. Lower-limb lean mass (LLM) was assessed using DXA, lower-limb muscle strength (LMS) using a dynamometer; and lower-limb muscle quality (LMQ) calculated as LMS/LLM. Knee pain and dysfunction were assessed using the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) index. PA was measured using pedometers. Linear mixed effect regression models, with adjustment for confounders, were used to estimate the association of within-person and between-person variability in PA, 25(OH)D and WOMAC score with muscle mass, strength and muscle quality.

Results: Both between-person and within-person increases in PA were associated with higher LLM, LMS and LMQ (all P<0.05). Within-person and between-person increases in knee pain and dysfunction were associated with lower LLS, LMQ but not LLM (all P<0.05). Between-person effects showed that higher 25(OH)D was associated with higher LLM, LMS and LMQ (all P<0.05); whereas, within-person increases in 25(OH)D was associated with a higher LMS, LMQ but not LLM.

Conclusions: Variability in 25(OH)D, knee pain and dysfunction within an individual over time relate to muscle changes in that individual. Increasing one’s own PA level further increases muscle mass, strength and quality supporting the clinical recommendation of promoting PA to reduce age-related muscle loss.