title: Correlation between serum vitamin D (25(OH)D) concentration and quadriceps femoris muscle strength in Indonesian elderly women living in three nursing homes.
abstract: OBJECTIVE
  to investigate the correlation between serum vitamin D (25(OH)D) concentration and quadriceps femoris muscle strength.
  
  
  METHODS
  this was a cross-sectional correlative study, conducted at three nursing homes in Jakarta and one nursing home in Bekasi in January 2005. The subjects were women aged 60 years or above. Those selected study subjects underwent quadriceps femoris muscle strength examination with Cybex dynamometer with 150 degrees/second speed, twice (three repetitions with 30 second rest time). The 25 (OH)D concentration was measured by ELISA.
  
  
  RESULTS
  out of 67 subjects who met the required criteria for this study, five subjects withdrew from the study during muscle strength examination. The mean age was 71.1 (SD 7.2) years old while the mean serum vitamin D concentration was 68.2 (SD 21.6) nmol/l. Vitamin D deficiency (<or= 50 nmol/l) was found in 22.6% of subjects. It was also found that the median (minimum-maximum) quadriceps femoris muscle strength was 40.00 (11-116) N.m. Approximately 82.3% of the subjects were of generalized muscle weakness. Correlation was found between serum 25 (OH)D concentration and quadriceps femoris muscle strength (r = 0.327; P = 0.009).
  
  
  CONCLUSIONS
  this study reveals that serum 25 (OH) D concentrations in Indonesian elderly women is correlated with quadriceps femoris muscle strength. The proportion of elderly women with muscle weakness is higher than the normal ones. The group with older age shows higher proportion of muscle weakness. Most subjects have normal serum vitamin D concentration.
authors: Department of Internal Medicine, Faculty of Medicine, University of Indonesia, dr. Cipto Mangunkusumo Hospital, Jakarta.
authors: Ikhwan
authors: I
authors: Rinaldi
authors: Siti
authors: S
authors: Setiati
authors: Maryantoro
authors: M
authors: Oemardi
authors: Wanarani
authors: W
authors: Aries
authors: T Z
authors: TZ
authors: Tamin
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002112:Calcifediol / Q000097:blood*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007214:Indonesia; D008875:Middle Aged; D009119:Muscle Contraction / Q000502:physiology*; D053580:Muscle Strength / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D009735:Nursing Homes; D052097:Quadriceps Muscle / Q000502:physiology*; D012016:Reference Values; D014808:Vitamin D Deficiency / Q000503:physiopathology*
chemical_list: D002112:Calcifediol