Desintrometría ósea en mujeres chilenas normales en edad fértil: correlación con valores referenciales y variables antropométricas / Dual X-ray absorptiometry [DEXA] in normal Chilean women: correlation between reference values and anthropometric variables

RESUMO

Background: Bone mineral density results are expressed as the number of standard deviations from reference values in similar populations. However, these reference values have not been obtained locally and there may be discrepancies between Chilean and other Hispanic populations. Aim: To evaluate the results of DEXA in healthy Chilean women and to correlate them with reference values and anthropometric parameters. Material and Method: We studied prospectively 166 normal women aged between 15 and 55 years, using a Hologic QDR 1000 equipment, yielding bone mineral density (BMD), bone mineral content (BMC) and bone area (A) in the lumbar spine (LS) and femoral neck (FN). These bone densitometric variables were correlated with weight, height and age of women and compared against the reference values of the Hologic equipment. Relation between BMC and A was evaluated using a regression analysis. Results: BMD and BMC were lower to reference values in most age groups, especially for LS. There was a significant correlation of BMD with A in LS (r 0.278, p <0.001), weight in both LS (r 0.382, p <0.0001) and FN (r 0.266, p <0.001), height in LS (r 0.258, p <0.001) and age in FN (r -0.231, p <0.01). Only in LS, regression analysis between A and BMC did not show direct proportionality. Conclusions: BMD of healthy Chilean women was lower than the reference values of the Hologic equipment for most age groups. Bone densitometric variables are non uniformly influenced by weight, height and size of bone structures (A) in normal women, especially in LS. Correct interpretation of DEXA requires the validation of reference values and to assess the value of bone area measurements (Rev Méd Chile 2004; 132 681-90).