Objective: To document prescribing patterns of lipid-modifying therapies in hypercholesterolemic patients, cholesterol goal attainment, and factors associated with cholesterol goal attainment in Norway.
Method: This was a retrospective, observational study using existing computerized patient records at 11 primary healthcare centers in Norway and the Norwegian Patient Register of hospital data. The study population was 3111 patients identified in the primary care database who were prescribed a lipid-modifying therapy between the dates of July 1987 and May 2003 and who were > or = 18 years of age at the time of the first prescription. Of these patients, 1337 patients had uncontrolled lipid measures at baseline. In the analysis of goal attainment, data were available for 877 (28% of the total study population) and 1144 (37%) patients with baseline and follow-up total cholesterol (TC) and/or low-density lipoprotein-cholesterol (LDL-C) levels after 4 and 12 months' treatment, respectively.
Outcome measures: Initial lipid-modifying therapy (drug and dosage), changes in initial lipid-modifying therapy, cholesterol goal attainment, and factors related to cholesterol goal attainment. Cholesterol treatment goals were defined as LDL-C <3.0 mmol/L and/or TC <5.0 mmol/L (as per the Second Joint Task Force of European Societies on the Prevention of Cardiovascular Disease).
Results: The initial lipid-modifying therapy was a HMG-CoA reductase inhibitor (statin) in 98% of patients, most often simvastatin (42%; mean initial dosage = 18.4 mg/day) or atorvastatin (34%; 12.7 mg/day). The median year of treatment initiation was 1999 and the mean duration of follow-up was 39 months. The initial prescription remained unchanged at year 1 for most patients (69%), whereas 17% discontinued drug treatment. Mean TC levels decreased from 7.36 mmol/L at baseline (n = 1337) to 5.31 mmol/L at 12 months (n = 1144; p < 0.05), whereas mean LDL-C levels decreased from 4.98 (n = 847) to 3.08 mmol/L at 12 months (n = 713; p < 0.05). These mean reductions occurred within 3 months of the initial prescription and did not change subsequently. A total of 32.9% of patients who were not at goal at baseline achieved cholesterol goal 12 months after initiating treatment. The factors related to cholesterol goal attainment at 12 months were: baseline TC level (odds ratio [OR] 0.64; 95% CI 0.58, 0.71), treatment with a statin (OR 8.60; 95% CI 1.13, 65.4), diagnosis of diabetes mellitus (OR 2.91; 95% CI 2.01, 4.21), and age (OR 1.02; 95% CI 1.01, 1.03).
Conclusions: Lipid-modifying therapy in Norway is dominated by statin monotherapy. In this analysis of primary-care patients, maximal reductions in cholesterol levels were seen within the first 3-4 months after therapy initiation. After 12 months of treatment, 67% of patients remained above recommended cholesterol levels. More effective and well tolerated treatment strategies are needed to improve the probability of patients achieving cholesterol treatment goals.