Bone mineral content and BMD measurements were done with dual energy x-ray absorptiometry using a Norland XR-26 densitometer (Fort Atkinson, Wis). The equipment has an accuracy and precision of 99 percent as documented with a phantom. Regions of interest that were assessed included total body, lumbar area of the spine (L2-4), and left hip (trochanter major, neck of femur, Ward’s triangle).
Quantitation of Inhaled Steroid
The total topical steroid doses, including both inhaled and nasal preparations and booster courses of systemic steroids, were calculated based on medical records. Drug compliance was checked by patient interview at the time of this study, and those who did not take inhaled steroids regularly as prescribed were excluded from the study. Only beclomethasone dipropionate (BDP) and budesonide (BUD) had been used. In the calculation of cumulative dose, they were considered to be equipotent Here generic allegra. In the evaluation of correlation between total cumulative dose and bone density, analysis was done twice: (1) the two preparations were considered equipotent, and (2) BUD was considered as having 50 percent of the systemic potency as BDP.
The BMD, expressed as both absolute values and z scores (as defined by [patient value—control group meanjdivided by control group SD) of the various regions of interest of patients were compared with values of matched control subjects using the Mann-Whitney U-test. The BMD levels of the female control subjects were verified to be within the normal distribution (± 2 SD) of the normal Chinese population in Hong Kong as reported by another group using similar equipment. However, normal data on such a large scale were not available for men for such validation. To assess the possible factors which may have contributed to a decrease in BMD in these patients, the following statistical analyses were done: BMD z scores of the 17 patients who never received systemic steroids were compared with those of the 13 patients who had received some systemic steroids in the past, using the Mann-Whitney U-test; BMD z scores of male and female patients were separately compared with those of their matched control subjects using the Mann-Whitney U-test; BMD z scores of the whole study group and the two sexes were correlated to the following parameters using Spearman rank correlation—cumulative inhaled steroid dose, average daily inhaled steroid dose, duration of inhaled steroid use, age, and BMI. The level of significance for all analyses was taken at p<0.05.