Non-steroidal anti-inflammatory drug use and markers of Parkinson's disease progression: A retrospective cohort study.

BACKGROUND:Previous studies demonstrated reduced incidence of Parkinson's disease (PD) with regular non-steroidal anti-inflammatory drug (NSAID) exposure, particularly ibuprofen. No studies have investigated the impact of NSAID exposure on markers of disease progression for established PD. METHODS:This is a retrospective observational study using two cohorts. The Deprenyl and Tocopheral Anti-Oxidative Therapy of Parkinsonism (DATATOP) study enrolled 800 drug naïve people with PD with a median follow-up duration of 6.5 years. The DATATOP primary outcome measures were mortality at last study visit. The Parkinson's Progression Markers Initiative (PPMI) cohort was limited to drug naïve PD participants (423 at time of analysis). The PPMI primary outcome measure was annual rate of change in ipsilateral putamen 123I-ioflupane binding ratio at four years study duration. Regular NSAID exposure was defined as any scheduled NSAID use (as needed use was excluded). Analysis was performed separately for recent exposure and cumulative exposure time (CET). RESULTS:Total CET median and interquartile range (years) for ibuprofen, non-aspirin NSAID, and aspirin were respectively 0.9 (0.3-2.9), 1.1 (0.3-2.6), and 1.5 (0.4-2.8) for DATATOP and 0.4 (0.01-2.2), 1.4 (0.3-4.4), and 5.5 (2.6-7.1) for PPMI. Exposure was usually discontinuous. Exposure to ibuprofen was low in both cohorts. There was no significant association between NSAID recent exposure or CET and primary outcome measures in either cohort. CONCLUSIONS:NSAID exposure in established PD does not appear to provide protective effect although exposure may not have occurred continuously enough in these two cohorts to provide benefit. Statistical power for ibuprofen exposure analyses was limited.