Population-based geographic variations in dxa bone density in Europe: The evos study

Abstract

Abstract. The purpose of this study was to investigate variations in bone density between 16 European populations, 13 of which were participants in the European Vertebral Osteoporosis Study (EVOS). Men and women aged 50-80 years were recruited randomly from local population registers, stratified in 5-year age bands. The other three centres recruited similarly. Random samples of 20-100% of EVOS subjects were invited for dual-energy X-ray absorptiometry (DXA) densitometry of the lumbar spine and/or proximal femur using Hologic, Lunar or Norland pencil beam machines or, in one centre, a Sopha fan.-beam machine. Crosscalibration of the different machines was undertaken using the European Spine Phantom prototype (ESPp). Highly significant differences in mean bone density were demonstrated between centres, giving rise to betweencentre SDs in bone density that were about a quarter of a population SD. These differences persisted when centres using Hologic machines and centres using Lunar machines were considered separately. The centres were ranked differently according to whether male or female subjects were being considered and according to site of measurement (L2-4, femoral neck or femoral trochanter). As expected, bone mineral density (BMD) had a curvilinear relationship with age, and apparent rates of decrease slowed as age advanced past 50 years in both sexes. In the spine, not only did male BMD usually appear to increase with age, but there was a highly significant difference between centres in the age effect in both sexes, suggesting a variability in the impact of osteoarthritis between centres. Weight was consistently positively associated with BMD, but the effects of height and armspan were less consistent. Logmithmic transformation was needed to normalize the regressions of BMD on the independent variates, and after transformation, all sites except the femoral neck in females showed significant increases in SD with age. Interestingly, the effect of increasing weight was to decrease dispersion in proximal femur measurements in both sexes, further accentuating the tendency in women for low body mass index to be associated with osteoporosis as defined by densitometry. It is concluded that there are major differences between BMD values in European population samples which, with variations in anthro~ pometric variables, have the potential to contribute substantially to variations in rates of osteoporotic fracture risk in Europe.

Geographic variation of bone mineral density and selected risk factors for prediction of incident fracture among Canadians 50 and older

“…The variation was larger than regional variation found in the U.S. [18], but smaller than geographic variation found within Norway, Mexico, Japan [19][20][21] or across Europe [22]. As expected, regional variation in the prevalence of osteoporosis (as defined by BMD T-scores≤−2.5) was related to underlying differences in the distribution of BMD.…”

Geographical variation in DXA bone mineral density in young European men and women. Results from the Network in Europe on male osteoporosis (NEMO) study

“…However this would only be of major importance where treatment decisions are made on the basis of a fixed T-score threshold as in the UK [12]. In previous work it has been observed that there are quite substantial between centre differences in BMD in older populations of men and women [6] and that rates of bone loss or gain differ between centres [13]. The between country and between centre differences in mean BMDs described in this paper will allow the study of whether these differences are apparently growing over time (implying an impact of ecology on the evolution of BMD) or whether they are constant across the range of adult ages in men and women.…”

“…This was done as described by Pearson et al [3], Kalender et al [5], and Lunt et al [6]. The minimum acceptable data for inclusion in the study was BMD at one measurement site (from femoral neck, trochanter, or L2-L4 spine), age, weight, and height at/or near the scan date.…”

Vitamin D deficiency, secondary hyperparathyroidism and bone mineral density in Pakistani and Norwegians living in Oslo, Norway / Vitamin D-mangel, sekundær hyperparathyroidisme og bentetthet hos pakistanere og nordmenn bosatt i Oslo

“…Tatt vitamin D-statusen i betraktning var dette et overraskende funn. På den annen side er nordmenn blant de med høyest bruddrate (14-16) og lavest verdi av bentetthet som er rapportert internasjonalt (17).…”