Short term HDL cholesterol decrease and cardiovascular risk

Trial description: During a GSK clinical trial, a decrease in HDL-C of up to 30-40% was seen in patients within the treatment arm. This study will be conducted to generate real world data that helps to quantify any increased risk of cardiovascular (CV) events associated with short term decreases in HDL-C. This is a retrospective cohort study to estimate the risk of CV events in subjects initiating statin therapy experiencing a decrease in HDL-C and remaining on treatment for <=6 months, compared to those with no change in HDL-C while on treatment for <=6 months.This study will select a sample of subjects >18 years of age and <85 years of age, with no ongoing malignancy, initiating statin therapy from 2006-2014. Subjects will be required to have 2 HDL-C measurements; 1 within 6 months before and 1 within 6 months after statin initiation. Subjects must have also discontinued statin therapy within 6 months of initiation and must not have experienced any of the pre-specified study outcomes within the time period of statin use. Study outcomes will be assessed using linked information from clinical practice research data link (CPRD), hospital episode statistics (HES), and office for national statistics (ONS) mortality data. The count of subjects initiating statins from 2006-2014 with HDL-C measurements within 6 months before and after statin initiation was 120674. It is expected that approximately 37400 subjects will discontinue statin use within 6 months of initiation. It is also expected that approximately 7480 statin initiators will have a decrease in HDL-C.