title: Prevalence of clinically relevant muscle weakness and its association with vitamin D status among older adults in Ecuador.
abstract: BACKGROUND
  Muscle weakness and 25-hydroxyvitamin D (25(OH)D) deficiency have been associated with adverse outcomes among older adults. However, little is known about the relationship between clinically relevant muscle weakness and 25(OH)D levels in Ecuador.
  
  
  OBJECTIVE
  To examine the prevalence of muscle weakness and its association with 25(OH)D status among subjects aged 60 years and older in Ecuador.
  
  
  METHODS
  The present study was based on data from 2205 participants in the first National Survey of Health, Wellbeing, and Aging. The Foundation for the National Institute of Health Sarcopenia Project criteria was used to examine muscle weakness prevalence rates. Gender-specific general linear and logistic regression models adjusted for potential confounders were created to compare mean 25(OH)D concentrations and 25(OH)D deficiency across muscle strength categories, respectively.
  
  
  RESULTS
  An estimated 32.2% of women and 33.4% of men had evidence of clinically relevant muscle weakness in Ecuador. In general, increased muscle weakness prevalence rates were present among Indigenous, residents in the rural Andes Mountains, underweight subjects, and those with a sedentary lifestyle. Muscle strength was significantly and directly correlated with mean 25(OH)D levels. After controlling for potential confounders, 25(OH)D deficiency prevalence rates were 31 and 43% higher among men and women with muscle weakness than those with normal strength, respectively.
  
  
  CONCLUSIONS
  One-third of older adults nationwide had evidence of muscle weakness. While the present study found a significant correlation between muscle strength and 25(OH)D concentrations, further research is needed to examine whether optimizing 25(OH)D levels may improve muscle weakness among older adults.
authors.affiliation: Department of Medicine, Laredo Medical Center, 1700 East Saunders, Laredo, TX, 78041, USA. corces07@yahoo.com.
authors.forename: Carlos H
authors.initials: CH
authors.lastname: Orces
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D004484:Ecuador / Q000453:epidemiology; D005260:Female; D006306:Health Surveys; D006801:Humans; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology*; D018908:Muscle Weakness / Q000097:blood / Q000150:complications / Q000453:epidemiology*; D015995:Prevalence; D012424:Rural Population; D017678:Sex Distribution; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood* / Q000150:complications / Q000453:epidemiology*; D014815:Vitamins
chemical_list: D014815:Vitamins; D014807:Vitamin D; C104450:25-hydroxyvitamin D
keywords: Ecuador; Grip strength; Older adults; Vitamin D; Weakness