Changes in cardiovascular risk factors by combined pharmacological and nonpharmacological strategies: the main results of the CELL Study

Abstract

Objective: The objectives of the Cost Effectiveness of Lipid Lowering (CELL) study were twofold: (i) to evaluate the effect on overall cardiovascular risk of two types of health care advice ("usual' and "intensive') given in primary care, with or without pharmacological medication, with the target being to attain a moderate decrease in cholesterol; (ii) to evaluate the ritual of daily medication on compliance with the health care advice.

Design: A prospective, double-blind, randomized, controlled trial of 18 months' duration.

Setting: The study was carried out in 32 health centres (out of a total of approximately 850) in Sweden.

Subjects: In all, 681 subjects, aged 30-59 years, were randomized. They had at least two cardiovascular risk factors in addition to moderate primary hyperlipidaemia (total cholesterol of at least 6.50 mmol L-1 on three occasions measured by Reflotron triglycerides less than 4.0 mmol L-1 and an LDL:HDL cholesterol ratio of more than 4.0). Most (87%) of the subjects were males; 626 subjects (92%) completed the 18-month follow-up.

Intervention: Half the subjects were randomized to 'intensive advice' given in group sessions led by doctors and nurses in primary care. The other half received 'usual advice'. In each of the two advice groups, one-third received an active lipid-lowering drug (pravastatin), one-third placebo, and one-third no drug at all. The tablets were titrated to achieve a 15% reduction in cholesterol.

Main outcome measures: Changes in the overall Framingham risk score, and the development of adverse events in each group.

Results: The change in Framingham risk score was significantly reduced only in subjects taking lipid-lowering medication (together with intensive advice -0.13; 95% CI-0.20, -0.06, and together with usual advice -0.16; 95% CI -0.23, -0.09). The other subjects receiving intensive advice tended to fare better than those on usual advice. Lifestyle was not influenced significantly over the study period. The ritual of daily medication did not affect the outcome.

Conclusion: As expected, lipid-lowering medication reduced serum cholesterol as well as overall cardiovascular risk in subjects with several risk factors for cardiovascular disease. There was no additive effect of intensive advice to these subjects. However, there was a meagre but significant effect of intensive advice in subjects not receiving active lipid-lowering drugs. One explanation for this difference may be that those on active lipid-lowering medication who had substantial drops in cholesterol might have felt less inclined to change their lifestyle compared with those on other treatment regimens who had less successful drops in cholesterol. There was no benefit from the ritual of taking daily medication.