Prevalence of vitamin D deficiency and secondary hyperparathyroidism during winter in pre-menopausal Bangladeshi and Somali immigrant and ethnic Finnish women: associations with forearm bone mineral density

Br J Nutr. 2012 Jan;107(2):277-83. doi: 10.1017/S0007114511002893. Epub 2011 Aug 9.


Secondary hyperparathyroidism (SHPT) is one of the outcomes of vitamin D deficiency that negatively affects bone metabolism. We studied the ethnic differences in vitamin D status in Finland and its effect on serum intact parathyroid hormone (S-iPTH) concentration and bone traits. The study was done in the Helsinki area (60°N) during January-February 2008. A total of 143 healthy women (20-48 years of age) from two groups of immigrant women (Bangladeshi, n 34 and Somali, n 48), and a group of ethnic Finnish women (n 61) were studied in a cross-sectional setting. Serum concentrations of 25-hydroxyvitamin D (S-25OHD) and S-iPTH were measured. Peripheral quantitative computed tomography measurements were taken at 4 and 66 % of the forearm length. In all groups, the distribution of S-25OHD was shifted towards the lower limit of the normal range. A high prevalence of vitamin D insufficiency (S-25OHD < 50 nmol/l) was observed (89·6 %) in the Somali group. The prevalence of SHPT (S-iPTH>65 ng/l) was higher (79·1 %) in Somali women than in Finnish women (16 %). There was a significant association between S-25OHD and S-iPTH (r - 0·49, P < 0·001). Ethnicity and S-25OHD together explained 30 % of the variation in S-iPTH. The total bone mass at all sites of the forearm, fracture load and stress-strain index was higher (P < 0·001) in Bangladeshi and Finnish women than in Somali women. The high prevalence of hypovitaminosis D, SHPT and low bone status in Somali women indicates a higher risk of osteoporosis.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • 25-Hydroxyvitamin D 2 / blood
  • Adult
  • Bangladesh / ethnology
  • Bone Density*
  • Calcifediol / blood
  • Cross-Sectional Studies
  • Emigrants and Immigrants*
  • Female
  • Finland / epidemiology
  • Forearm
  • Humans
  • Hyperparathyroidism, Secondary / blood
  • Hyperparathyroidism, Secondary / epidemiology*
  • Hyperparathyroidism, Secondary / ethnology
  • Hyperparathyroidism, Secondary / etiology
  • Middle Aged
  • Parathyroid Hormone / blood
  • Premenopause
  • Prevalence
  • Seasons
  • Severity of Illness Index
  • Somalia / ethnology
  • Urban Health / ethnology
  • Vitamin D Deficiency / blood
  • Vitamin D Deficiency / epidemiology*
  • Vitamin D Deficiency / ethnology
  • Vitamin D Deficiency / physiopathology
  • Young Adult


  • PTH protein, human
  • Parathyroid Hormone
  • 25-Hydroxyvitamin D 2
  • Calcifediol