[Clinical study of the month. The ALLHAT-LLT trial].

ALLHAT-LLT was part of the ALLHAT study. The purpose was to determine whether pravastatin compared with usual care reduces all-cause mortality in older, moderately hypercholesterolaemic, hypertensive patients with at least one additional coronary heart disease (CHD) risk factor. 10,355 ambulatory patients, aged 55 years or more, with LDL cholesterol of 120-189 mg/dl (or, 100-129 mg/dl if known CHD) and triglycerides < 350 mg/dl, were randomised to pravastatin (40 mg/d; n = 5,170), or usual care (n = 5,185). Mean age was 66 years; 49% were women; 38% were black and 23% hispanic; 14% had a history of CHD and 35%, type 2 diabetes. Baseline mean total cholesterol was 224 mg/dl; LDL-C, 146 mg/dl; HDL-C, 48 mg/dl, and triglycerides, 152 mg/dl. Mean follow-up was 4.8 years. Among usual care patients, 32% of those with known CHD and 29% of those without CHD started taking lipid-lowering drugs. At year 4, total cholesterol was reduced by 17.2% with pravastatin and by 7.6% with usual care. A random sample had their LDL-C levels assessed: there was a reduction of 28% with pravastatin and of 11% with usual care. All-cause mortality was similar in the two groups (RR, 0.99; 95% CI, 0.89-1.11; p = 0.88), with 6-year mortality rates of 14.9% (pravastatin) and 15.3% (usual care). CHD event-rates were not different between the two groups (RR, 0.91; 95% CI, 0.79-1.04; p = 0.16); 6-year CHD event rates were 9.3% (pravastatin) and 10.4% (usual care), respectively. These results are likely due to the small differential in total cholesterol (9.6%) and LDL-C (16.7%) between pravastatin and usual care, compared with prior statin trials. Such an unusual differential essentially results from the open table of the study and from the possibility of prescribing a statin in the usual care group.