In a previous audit of statin efficacy and attainment of lipid targets we reported to this society that in the Aberdeen hypertension clinic only 45.4% of patients on statin therapy met the current total cholesterol (TC) target (McIntyre et al., 2000). Of these 23% of treated patients failed to meet target because they were prescribed low dose statin with failure to uptitrate according to response, while 32% of the total cohort failed to achieve target because they experienced a poor response to statin, raising the possibility of poor compliance with therapy.

The aims of this study were, using a questionnaire and records of pre and post treatment lipid levels, to determine whether patient education, understanding, self reported compliance, and co-medication affect attainment of target lipid levels. Consecutive patients, currently on statin, were recruited into the study. Each was asked for informed consent, and once given, asked to complete a 15 point questionnaire which covered areas of cardiovascular risk education and under-standing, co-prescribed medication, type and dose of statin together with time of taking medication, and self reported compliance. Pre and post treatment lipid profiles were obtained from the central Biochemistry Department computer. 184 patients who completed the questionnaire were recruited, 45.6% were on simvastatin for primary and 54.4% for secondary prevention. The average age was 64.6±10 years (range 38-93), 56% were male, 25.6% diabetic and 16.6% smokers. The average dose of statin was 20.7±8.1mg/day, length of treatment was 41.1±28.7 months, and number of co-prescribed medicines 4.78±1.9 per patient. Only 9.2% of patients identified hypercholesterolaemia, and 7% smoking as one of their actual CHD risk factors, while 36% correctly identified hypertension. Only 7.6% of patients identified cholesterol reduction and 26% smoking cessation as important for CHD risk reduction. 32.7% (55) of patients failed to respond as expected to their statin dose with a TC reduction of 14.1±8.5% vs 37.1±8.1% (p<0.01) for those who met target, suggesting a lack of efficacy. Otherwise the responders differed only in having a greater pre-treatment TC (6.9±1.1 vs 6.4±1.2, p<0.05), duration of therapy (44.9±29.6 vs 33.6±25.8 months, p<0.05), systolic blood pressure control (149.3±18.9 vs 156.6±22.1 mm Hg, p<0.05), and to be more aware of hypertension as one of their risk factors (40,7 vs 25.5%, p<0.05). Less than ideal compliance with therapy was reported by 44% of patients, who were younger (61.9±9.7 vs 66.6±9.7 years, p< 0.01), and experienced less of a cholesterol reduction (26.1±12.8 vs 32.0±13.9%, p<0.01). More patients who admitted good compliance also admitted to receiving information from the doctor (85% vs 68%, p<0.01) and to being happy with there TC level (47% vs 30%, p<0.05). The time of dosing was also significantly associated with statin efficacy with night time dosing more efficacious than morning dosing. This study confirms that achieving lipid targets is associated with better BP control and awareness of risk factors while self admitted poor compliance is associated with a reduced statin efficacy and less educational input.

McIntyre C, McLay JS., (2000) Br J Clin Pharmacol 49: 513.