Lymphangioleiomyomatosis and Tuberous Sclerosis Complex in Quebec: Prevalence and Health-care Utilization

Lymphangioleiomyomatosis (LAM) is a manifestation of tuberous sclerosis complex (TSC) that causes destruction of the lung and chronic respiratory failure. Population-based estimates of demographics, clinical outcomes, and health-care utilization are lacking for TSC and LAM.

Data on demographics, clinical outcomes, and health-care utilization in the Quebec ministerial provincial health-care database were analyzed for their association with TSC and LAM.

A total of 1,004 subjects with TSC were identified using International Classification of Diseases, Ninth and 10th Revisions, codes for a prevalence of one in 7,872 people. There were 38 subjects with LAM, nine of whom also had TSC. Mean ages as well as the mean age at death were lower in the LAM and TSC group than in the control group. Mortality rates were higher in subjects with LAM than in those with TSC or in control subjects. Subjects with LAM experienced more medical visits and hospitalizations than did those with TSC and control subjects; these were associated with higher health-care costs. Frequently prescribed drugs in TSC or LAM included anticonvulsants, antidepressants, and sedatives; the use of mammalian target of rapamycin inhibitors was uncommon.

The prevalence of TSC in Quebec, Canada, is similar to estimates from previously published surveys. LAM is likely underreported, perhaps due to suboptimal case identification or referral. Health-care utilization and mortality for LAM are high, suggesting that timely diagnosis and therapy could be beneficial. Mental health disorders may be an unrecognized clinical feature of LAM. These results provide a population-based background for policymakers and researchers to better address the needs of patients with TSC and LAM.