title: Lifestyle and biologic contributors to proximal femur bone mineral density and hip axis length in two distinct ethnic groups of premenopausal women.
abstract: Although relatively little is known about osteoporotic risk factors in women from the Indian subcontinent, osteoporotic fractures usually occur 10-20 years earlier in Indian men and women compared with their western Caucasian counterparts. The primary purpose of this cross-sectional study was to determine the relative contributions of ethnicity, reproductive history, body size (height, weight) and composition, bone turnover, serum 25(OH)vitamin D(3) [25(OH)D(3)], dietary intake (of calcium, fiber and alcohol) and energy expenditure to femoral bone mineral density (BMD) in Indian and Pakistani (Indian/Pakistani; n = 47) versus American (n = 47) Caucasians. We also contrasted femoral BMD and hip axis length in these two distinct groups of premenopausal females living in the USA. The Indian/Pakistani (0.875 +/- 0.096) women had lower (p = 0.0014) femoral BMD (g/cm(2)) than their American (0.937 +/- 0.088) counterparts, placing them at greater osteoporotic risk. However, the shorter (p = 0.0002) hip axis length (cm) of the Indian/Pakistani (10.54 +/- 0.57) versus American (11.11 +/- 0.78) Caucasians might attenuate hip fracture risk in the former group. Significant contributors to proximal femur BMD were maximum non-pregnant lifetime weight, age at menarche, ratio of summation sigma central-to-peripheral skinfold thicknesses, calcium intake from milk and usual alcohol intake. Although serum 25(OH)D(3) and urinary N-telopeptide concentrations did not contribute to femoral BMD in the regression models, the lower (p<0.0001) serum 25(OH)D(3) (33.1 +/- 16.5 vs 64.0 +/- 22.0 nmol/l) and higher (p = 0.0004) urinary N-telopeptide (45.9 +/- 43.3 vs 18.9 +/- 18.7 nmol BCE/mmol) values in Indian/Pakistani versus American Caucasians, respectively, coupled with their lower BMD, places the Indian/Pakistani women at greater osteoporotic risk. These results suggest that a clinical trial to increase BMD and reduce osteoporotic risk is warranted in this ethnic group of premenopausal women.
authors.affiliation: Department of Food Science & Human Nutrition, Iowa State University, Ames, Iowa, USA. alekel@iastate.edu
authors.forename: D L
authors.initials: DL
authors.lastname: Alekel
authors.forename: E
authors.initials: E
authors.lastname: Mortillaro
authors.forename: E A
authors.initials: EA
authors.lastname: Hussain
authors.forename: B
authors.initials: B
authors.lastname: West
authors.forename: N
authors.initials: N
authors.lastname: Ahmed
authors.forename: C T
authors.initials: CT
authors.lastname: Peterson
authors.forename: R K
authors.initials: RK
authors.lastname: Werner
authors.forename: B H
authors.initials: BH
authors.lastname: Arjmandi
authors.forename: S C
authors.initials: SC
authors.lastname: Kukreja
mesh_terms: D000328:Adult; D015519:Bone Density / Q000502:physiology*; D002118:Calcium / Q000008:administration & dosage; D004032:Diet; D005260:Female; D005269:Femur / Q000502:physiology*; D006621:Hip Joint / Q000033:anatomy & histology*; D006801:Humans; D007194:India / Q000208:ethnology; D008019:Life Style; D015663:Osteoporosis, Postmenopausal / Q000209:etiology; D010154:Pakistan / Q000208:ethnology; D017697:Premenopause / Q000502:physiology*; D012044:Regression Analysis; D012307:Risk Factors; D014481:United States
chemical_list: D002118:Calcium