Physical Performance Scores

1
Grip Strength Is Improved by Vitamin D
Supplementation in African American Women Melissa
Li-Ng, M.D.,1,3 John F. Aloia, M.D.2 and Jason A.
Wexler, M.D.1,3 1Division of Endocrinology,
Georgetown University Medical Center, Washington,
DC 2Winthrop-University Hospital, Mineola, NY
3Division of Endocrinology, Washington Hospital
Center
Physical Performance Scores

• The Short Physical Performance Battery (SPPB) was
  administered to assess strength, endurance and
  balance. Subjects were asked to perform a balance
  assessment, a timed 4-meter walk, and a
  chair-rise test. The higher the SPPB score, the
  better the physical performance. The maximum
  SPPB score is 12.
• A dosing algorithm developed from a prior study
  determined the dose of vitamin D3 based on the
  baseline serum 25-OHD level. If the subjects
  25-OHD level was mcg of vitamin D3 per day. If her 25-OHD level
  was between 45 and 75 nmol/L, she received 70
  mcg/day. If her 25-OHD level was 75 nmol/L, she
  did not receive any vitamin D supplementation.

• BACKGROUND
• Muscle weakness is a prominent feature of the
  clinical syndrome of vitamin D deficiency.
• Randomized clinical trials have shown improved
  muscle strength and reduced risk of falling in
  elderly women supplemented with vitamin D and
  calcium.
• Lower 25-hydroxyvitamin (25-OHD) concentration
  and a higher parathyroid hormone (PTH)
  concentration are associated with loss of grip
  strength and muscle mass.
• The high prevalence of vitamin D deficiency and
  secondary hyperparathyroidism in African
  Americans could influence the loss of muscle mass
  and strength with aging in this population.
• Older African Americans have not been studied in
  vitamin D intervention trials.
• HYPOTHESIS
• We hypothesized that vitamin D supplementation to
  increase 25-OHD levels to optimal levels 75
  nmol/L will result in improvement in strength and
  physical performance in older African American
  women.
• AIMS
• The primary aim of this study was to answer the
  following question Does vitamin D
  supplementation influence physical performance in
  African American women?
• METHODS
• A cohort of African American postmenopausal women
  that participated in a previous study on vitamin
  D and bone density were invited to participate.
  African American ancestry was assessed by
  self-declaration.
• Participants had a baseline history and physical
  and 3 follow-up visits at 1 week, 2 months, and 4
  months.
• Grip strength was measured using a handgrip
  dynamometer. Isometric grasp was measured in the
  dominant hand. The mean of three measurements was
  recorded.

P
P NS
P NS
P NS
RESULTS Patient characteristics and baseline
values

• Only grip strength improved significantly
  (pconcentrations increase of 6 when compared to those above 50
  nmol/L.
• Physical performance at baseline was
  exceptionally good in this cohort. The mean
  baseline overall score was 11.5 vs. a mean of
  9.3 for 70-year olds. The grip strength was 61.2
  pounds vs. a mean of 49.6 for 65- to 69-year old
  females.
• The daily dose of 70 or 100 mcg resulted in a
  mean 25-OHD level of 90.6 (24.3) nmol/L at the
  end of the study.

Note BMI body mass index 25-OHD
25-hydroxyvitamin D PTH parathyroid hormone

• 52 women participated in this study.
• The dosing algorithm determined that 9 patients
  were not given vitamin D3, 23 were given 70 mcg/d
  and 20 were given 100 mcg/d. The 9 patients not
  given vitamin D were omitted from the analyses.
  The mean dose of vitamin D3 was 69.4 mcg/d (2776
  IU/d).