Timing of simvastatin treatment

Editor—The paper by Wallace et al on the timing of administering simvastatin is interesting but flawed because of assessing cholesterol concentrations at one time point and the relation of this time point to time of drug dosing and diurnal variations in cholesterol concentration.¹,² This difficulty is compounded by the fact that, contrary to the BMJ's own advice to contributors, this trial is not reported according to CONSORT guidelines.³ Could these details not have been reported electronically?

These issues aside, the paper has important implications for primary care. From April this year the salaries of general practitioners in the United Kingdom will depend in part on their recording of patients' cholesterol concentrations.⁴ Attaining a total cholesterol concentration of ≤ 5 mmol/l in up to 60% of patients with coronary heart disease, diabetes, and stroke accounts for 27 quality points.

In the population described 77% of evening dosed patients would achieve this target compared with 61% of patients taking their dose in the morning—assuming morning testing and a mean baseline cholesterol concentration of 4.4 mmol/l. In many populations, the mean cholesterol concentration of the groups for whom quality points are available may be higher. Small variations in serum cholesterol for a practice population could therefore have a substantial impact on income. The validity of such a measure as an index of quality seems questionable.

On the basis of these data, prudent practitioners may ask their patients to take their statin at night and base their annual cholesterol check on a morning blood sample. This may or may not lead to improvements in cardiovascular health. However it should lead to improvements in practice finances.