Association of Statin Use and High Serum Cholesterol Levels With Risk of Primary Open-Angle Glaucoma.

IMPORTANCE The use of statins (hydroxymethylglutaryl coenzyme A inhibitors) has been associated with a lower risk of primary open-angle glaucoma (POAG); however, results have been conflicting, and little is known about the association between high cholesterol levels and POAG. OBJECTIVE To assess the association of elevated cholesterol levels and statin use with incident POAG. DESIGN, SETTING, AND PARTICIPANTS This study used data collected biennially from participants aged 40 years or older who were free of glaucoma and reported eye examinations, within 3 population-based cohorts: the Nurses' Health Study (N = 50710; followed up from 2000 to 2014), the Nurses' Health Study 2 (N = 62992; 1999-2015), and the Health Professionals Follow-up Study (N = 23080; 2000-2014). Incident cases of POAG were confirmed by medical record review. The analyses were performed in January 2019. EXPOSURES Biennially updated self-reported information on elevated cholesterol level status, serum cholesterol levels, and duration of statin use. MAIN OUTCOMES AND MEASURES Multivariable-adjusted relative risks (RRs) and 95% CIs were estimated using Cox proportional hazards regression models on pooled data, with stratification by cohort. RESULTS Among the 136782 participants in the 3 cohorts (113702 women and 23080 men), 886 incident cases of POAG were identified. Every 20-mg/dL increase in total serum cholesterol was associated with a 7% increase in risk of POAG (RR, 1.07 [95% CI, 1.02-1.11]; P = .004). Any self-reported history of elevated cholesterol was also associated with a higher risk of POAG (RR, 1.17 [95% CI, 1.00-1.37]). A history of any statin use was associated with a 15% lower risk of POAG (RR, 0.85 [95% CI, 0.73-0.99]). Use of statins for 5 or more years vs never use of statins was associated with a 21% lower risk of POAG (RR, 0.79 [95% CI, 0.65-0.97]; P = .02 for linear trend). The association between use of statins for 5 or more years vs never use of statins and risk of POAG was more inverse in those who were older (>= 65 years: RR, 0.70 [95% CI, 0.56-0.87] vs <65 years: RR, 1.05 [95% CI, 0.68-1.63]; P = .01 for interaction). CONCLUSIONS AND RELEVANCE Among adults aged 40 years or older, higher serum cholesterol levels were associated with higher risk of POAG, while 5 or more years of statin use compared with never use of statins was associated with a lower risk of POAG.