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Screening for lymphangioleiomyomatosis by high-resolution computed tomography in young, nonsmoking women presenting with spontaneous pneumothorax is cost-effective.

RATIONALE
Women with pulmonary lymphangioleiomyomatosis (LAM) who present with a sentinel spontaneous pneumothorax (SPTX) will experience an average of 2.5 additional pneumothoraces. The diagnosis of LAM is typically delayed until after the second pneumothorax.


OBJECTIVES
We hypothesized that targeted screening of an LAM-enriched population of nonsmoking women between the ages of 25 and 54 years, who present with a sentinel pneumothorax indicated by high-resolution computed tomography (HRCT), will facilitate early identification, definitive therapy, and improved quality of life for patients with LAM.


METHODS
We constructed a Markov state-transition model to assess the cost-effectiveness of screening. Rates of SPTX and prevalence of LAM in populations stratified by age, sex, and smoking status were derived from the literature. Costs of testing and treatment were extracted from 2007 Medicare data. We compared a strategy based on HRCT screening followed by pleurodesis for patients with LAM, versus no HRCT screening.


MEASUREMENTS AND MAIN RESULTS
The prevalence of LAM in nonsmoking women, between the ages of 25 and 54 years, with SPTX is estimated at 5% on the basis of the available literature. In our base case analysis, screening for LAM by HRCT is the most cost-effective strategy, with a marginal cost-effectiveness ratio of $32,980 per quality-adjusted life-year gained. Sensitivity analysis showed that HRCT screening remains cost-effective for groups in which the prevalence of LAM in the population subset screened is greater than 2.5%.


CONCLUSIONS
Screening for LAM by HRCT in nonsmoking women age 25-54 that present with SPTX is cost-effective. Physicians are advised to screen for LAM by HRCT in this population.