Statins have become a mainstay in the treatment of hyperlipidemia, based on their potency and favorable side-effect profile. Drug choice is presumed to be guided by the estimated degree of low-density lipoprotein (LDL) cholesterol lowering required in a particular patient and the projected efficacy of any drug-dose combination, as contained in the package inserts for each medication. We investigated whether these expectations were met in a clinical practice.

Data were analyzed for 367 hyperlipidemic patients in a preventive cardiology practice who were not taking statins at entry, who were given a standard statin dose at their first visit, and who had at least one follow-up visit on the same drug/dose. Expected LDL cholesterol reductions were calculated for each patient based on guidelines in the package inserts for each drug.

The mean (±SD) observed LDL cholesterol reduction of 26% ± 20% was significantly less than expected (34% ± 7%, P < 0.001). The ratio of observed to expected reduction was not different for the three statins used (atorvastatin, 0.79 ± 0.48; simvastatin, 0.88 ± 0.61; pravastatin, 0.75 ± 0.69; P = 0.39).

The use of statins in a clinical practice led to observed reductions in LDL cholesterol level that were significantly less than those projected by package insert guidelines. We believe this gap reflects the reduced patient compliance frequently observed in clinical practice settings, rather than any inherent difference in statin responsiveness of a practice versus a trial population. Physicians should be aware of this disparity when using statins in the clinical setting.