The prevalence of acute response to bronchodilator in pulmonary lymphangioleiomyomatosis

Objective: The objective of this study was to evaluate the prevalence of acute bronchodilator responses in patients who were evaluated for pulmonary lymphangioleiomyomatosis. Methodology: This study was a retrospective review of the medical records of 50 patients, who were assessed for lymphangioleiomyomatosis from 1978 to 2002 at Mayo Clinic in Rochester, Minnesota, and Jacksonville, Florida, USA. Each medical record was reviewed for pertinent clinical and pulmonary function test data, including results for lung volume and flow, diffusing capacity and response to bronchodilator. Results: At initial testing, the mean FEV₁/FVC ratio for the whole group was 60%; 35 patients (70%) had airflow obstruction; five patients (10%) had only restriction; and 10 (20%) had neither restriction nor obstruction. Three patients (6%) showed a positive response to bronchodilator at initial testing and only one patient showed a positive response at 1 year. Pulmonary function testing at 1-year follow up was available in a subgroup of this cohort (23 patients; 46%), and only one patient (2%) had a positive response to bronchodilator. Although there was a statistically significant decrease in the FEV₁/FVC ratio (from 64% to 62%; P = 0.02), no other differences were found at 1-year follow up. Conclusions: In its advanced state, lymphangioleiomyomatosis produces irreversible airflow obstruction. A positive response to bronchodilator was unusual. Other measures of pulmonary function showed little or no change over a 12-month period.