SSRI/SNRI ANTI-DEPRESSANT INDUCED INTERSTITIAL LUNG DISEASE: A CASE SERIES AND CASE- CONTROL STUDY

Abstract

SSRI and SNRI anti-depressants are widely prescribed in the elderly population. For unknown reasons, the incidence of interstitial lung disease (ILD) is increasing in western populations. There are published case reports and references on the Pneumotox web site (www.pneumotox.com) linking SSRIs/SNRIs to development of ILD and/or airway involvement (ILD/AWI). A case of venlafaxine induced ILD/AWI led us to explored this association in more detail. We report a series of 5 cases and a case control study examining the association between SSRI/SNRI usage and presence of ILD/AWI in an elderly population. Participants were all 296 elderly people followed in a primary care geriatric practice. A chart audit of the electronic medical record was done to identify cases and controls. The case definition included chronic respiratory symptoms and presence of ILD/AWI on CT or CXR. SSRI/SNRI usage was standardized to 10mg of citalopram and person-month (p-m) exposure was calculated. There were 24 cases identified and 272 controls. Their mean ages were 90.5 and 88.6 (ns) respectively. There were 16/24 cases exposed to SSRI/SNRI and 97/175 controls. The Odds Ratio was 3.61, 95% CI 1.49–8.74, p 0.007. The mean p-m exposure to SSRI/SNRI was 129.3 months for cases and 27.1 for controls (P<0.001). We conclude that SSRIs and SNRIs were significantly associated with the risk of ILD/AWI. Because of their wide spread usage, further studies should be done to validate these findings. Prescribers should be cautious to monitor for development of insidious pulmonary symptoms and signs when these drugs are prescribed.