Forearm bone mineral density by age in 7,620 men and women: the Tromsø study, a population-based study.
Population-based studies of adult forearm bone mineral density (BMD) by age are scarce, and standardized reference values are lacking. In this cross-sectional study, men aged 55-74 years, women aged 50-74 years, and representative 5-10% samples of remaining age groups between 25 and 84 years living in Tromsø, Norway, were invited for forearm BMD measurement in 1994-1995. The authors measured 3,062 men and 4,558 women (response rate, 78%) by single x-ray absoptiometry at distal and ultradistal forearm sites. Up to age 50, the mean BMD difference was -0.1% per 1-year age group in both sexes. After age 50, the mean BMD difference per 1-year age group was -0.6% in men and -1.3% (distal) and -1.5% (ultradistal) in women. The BMD by age curve was linear for men throughout senescence, but women had a slope change to -0.7% (distal) and -0.8% (ultradistal) per 1-year age group from the 65- to 69-year age group. BMD levels and BMD by age association in the general population (n = 7,620) and in the population without bone-threatening diseases or medication (n = 5,179) were similar. Only longitudinal studies can clarify whether cohort effects or longitudinal BMD development patterns explain these cross-sectional results.
Institute of Community Medicine, University of Tromsø, N-9037 Tromsø, Norway. gro.berntsen@ism.uit.no
G K
GK
Berntsen
V
V
Fønnebø
A
A
Tollan
A J
AJ
Søgaard
J H
JH
Magnus
D015502:Absorptiometry, Photon; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015519:Bone Density; D003430:Cross-Sectional Studies; D005260:Female; D005542:Forearm; D006801:Humans; D008297:Male; D008875:Middle Aged; D009664:Norway / Q000453:epidemiology; D010024:Osteoporosis / Q000453:epidemiology*; D015663:Osteoporosis, Postmenopausal / Q000453:epidemiology; D012016:Reference Values; D012737:Sex Factors