Abstract
Purpose:
At our institution, requests for consultation are occasionally received to assess cataract occurrence and risk associated with systemic medications. This study was conducted to investigate cataract risk associated with the use of atypical antipsychotics.
Methods:
A large health claims database (The British Columbia Linked Health Database) from British Columbia, Canada was used for this nested case-control study. Cases were defined as those newly diagnosed with cataracts defined as the first cataract procedure performed. For each case, four controls were randomly selected using a density based sampling approach and matched to the cases by age and calendar time. Rate ratios were calculated for users of atypical and typical antipsychotics adjusting for possible confounding variables, such as steroid use, uveitis, and others.
Results:
162,501 cases of cataract surgery and 650,004 controls were included. The adjusted rate ratio (aRR) for current users of atypical antipsychotics was 0.84 (95% CI, 0.80-0.89) compared to none users. A greater number of prescriptions filled in the year prior to cataract surgery, compared to the median number of filled prescriptions, was associated with lower clinically significant cataract risk (aRR, 0.74; 95% CI, 0.69-0.80) than those with fewer prescriptions filled (aRR, 0.92; 95% CI, 0.85-0.99).
Conclusions:
A possible protective effect of atypical antipsychotic use for risk of clinically significant cataracts was established. Potential mechanisms for this protective effect will be discussed.
Keywords: 445 cataract •
464 clinical (human) or epidemiologic studies: risk factor assessment •
503 drug toxicity/drug effects