[Bone mineral density and risk factors for developing osteoporosis in bronchial asthma patients]

To estimate mineral bone tissue density (MBTD) and risk factors for osteoporosis in patients with bronchial asthma (BA).

A cross-sectional study included 119 patients (48 males and 71 females) aged 18 to 49 years who had no diseases or states that can induce MBTD, except BA. The patients were divided into 3 groups: 1) those untreated with glucocorticoids (GC); 2) those who received inhaled GC; and 3) those who permanently took oral and inhaled GC. The patients underwent questionnaire survey, double-power X-ray absorption of the lumbar vertebral column and proximal femur, and X-ray study; forced expiratory volume per sec and peak expiratory function were measured.

In Group 1 patients, there was a high incidence of osteopenia that increased with the severity of BA. About 2.5-year therapy with inhaled GC in large and small doses had no impact on MBTD. The prolonged use of systemic GC caused a marked reduction in MBTD and led to the development of osteoporetic fractures. Changes were detected in both the lumbar spine and proximal femur. In males and females, MBTD decreases were equal. MBTD correlated with the duration of GC therapy and with age at its initiation, but not with the daily dose of GC. In 15.4% of the patients, MBTD remained in the normal range despite the prolonged use of GC in large doses. Osteoporetic fractures were observed at the values of MBTD, which had not reached the stage of osteoporosis according to the WHO criteria, which was indicative of qualitative GC-induced bone tissue changes.

GC is an important, but not alone, risk factor for osteoporosis in asthmatic patients. The high rate of low MBTD among the patients receiving no GC suggests that it is necessary to make an early diagnosis and to perform rational treatments.