Case-control studies exposure databases

A case-control study using data from healthcare databases in Ontario from 1994 to 2000 identified 1051 patients who had been admitted to hospital with digoxin toxicity. Of these, 5 patients (0.5%) had been exposed to cefuroxime in the preceding 3 weeks when compared with 0.3% of controls, suggesting that digoxin toxicity was not significantly related to cefuroxime exposure. ... 

Urinary tract In a case-control study the risk of acute interstitial nephritis (AIN) and acute kidney injury (AKI) was estimated for exposure to nonselective NSAIDs (nsNSAIDs), (proton pump inhibitors) PPIs and co-exposure to both (nsNSAID + PPI). There were 68 AIN cases identified from a primary care database from the United Kingdom (Clinical Practice Research Datalink) who were matched to 3347 controls. The risk of AIN for use of PPIs only was 3.2 (95%CI 0.8-12.8), of nsNSAIDs only was 1.9 (95%CI 0.7-5.5) (Cl, confidence interval). For individual nsNSAIDs diclofenac showed an odds ratio (OR) of 2.7 (95%CI 0.6-10.9) piroxicam provided an OR of 28.0 (2.2-365.1), however, the estimates are affected by the small number of cases and matched controls. Regarding AKI (n=27,982 cases n= 1,323,850 matched controls), the risk was increased by 31% for use of nsNSAIDs only (OR 1.31 95%CI 1.25-1.37) and for nsNSAIDs + PPI by 33% (OR 1.33 95%CI 1.07-1.64) [2 =]. 

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