EDITOR—In his editorial Rosengren considers that reaching target cholesterol concentrations may be better than relative reductions.1 He stated that “in observational studies a prolonged difference in usual serum cholesterol value of 0.06 mmol/l is associated with an almost 30% reduction in risk of coronary disease.”

No one would question the need for reducing serum cholesterol concentration in large proportions of adults in Western populations. However, the subject of cholesterol concentration and its pathological importance is complex.

Known risk factors for coronary heart disease, of which serum cholesterol concentration is one,explain only half of the variance in the occurrence of the disease.2 There are also numerous contextual problems. For example, in the Sheffield risk table, cholesterol reduction may be called for at 5.5 mmol/l in those at high risk, whereas intervention may not be needed until 9.0 mmol/l in those at low risk.3 The experience of coronary heart disease also differs between Belfast and Toulouse. Although mean …