Prevalence of Osteopenia in Drug-Naive Patients With Antineutrophil Cytoplasmic Antibody–Associated Vasculitis

Objectives To examine the bone mineral density and prevalence of osteoporosis and osteopenia in glucocorticoid- and immunosuppressive drug–naive patients younger than 55 years with antineutrophil cytoplasmic antibody–associated vasculitis (AAV). Methods This was a cross-sectional study. We reviewed the medical records of 35 AAV patients and 35 age-, sex-, and body mass index (BMI)–matched control subjects. We collected clinical data such as AAV-related variables and conventional risk factors for osteoporosis and assessed bone mineral density and the prevalence of osteoporosis and osteopenia in both groups. Categorical and continuous variables were compared between the 2 groups using the χ 2 or Fisher exact test and Mann-Whitney U test, respectively. Multivariate logistic regression analysis was used to calculate the odds ratio (OR). Results There were no statistically significant differences between the demographical data of AAV patients and control subjects. Patients with AAV showed significantly higher frequencies of conventional risk factors for osteoporosis than the control subjects, except for hyperthyroidism. Osteopenia was found more commonly in AAV patients than in control subjects (57.1% vs. 31.4%, p = 0.030). In the univariate logistic regression analysis, BMI (OR, 0.813) and AAV (OR, 2.620) were associated with osteopenia in all participants. In the multivariate analysis, both BMI and AAV were associated with osteopenia, but this was not statistically significant. In contrast, when analyzing AAV patients only, neither conventional risk factors nor AAV-related variables were associated with the prevalence of osteopenia. Conclusions Antineutrophil cytoplasmic antibody–associated vasculitis and BMI were both associated with osteopenia.