[Changes in lipids and lipoproteins caused by the beta-blocking agents used as antihypertensives]

It is certain that atherosclerosis is multi-factorial. Amongst the numerous risk factors two are particularly important: hypertension and primary or secondary abnormalities of plasma lipids and lipoproteins (high levels of total cholesterol, LDL and VLDL cholesterol, triglycerides or VLDL triglycerides, apoprotein B, low levels of HDL cholesterol, apoprotein A1 and probably HDL2). On the basis of a general review of the literature, the authors evaluate the changes in lipids, lipoproteins and apoproteins induced by different beta-blockers. Overall, the most constant and most obvious (particularly in hyperlipidaemic patients) disturbances combine an increase in total triglycerides or VLDL triglycerides and a fall in HDL cholesterol. There is little change in total cholesterol or LDL cholesterol. Side effects seen with most beta-blockers, cardioselective or not, differ in degree from one drug to another. They are particularly marked with some (propranolol) while they are virtually absent with others (pindolol). The mechanism of action is discussed (essentially inhibition of extra-hepatic lipoprotein lipase activity). These findings would seem to lead to the following practical conclusions: 1) Before starting antihypertensive treatment it is important to confirm lipid and lipoprotein levels, particularly bearing in mind the epidemiological links between moderate essential hypertension and lipoprotein abnormalities, especially those with a component of hypertriglyceridaemia. 2) Lipid profile including estimation by precipitation of HDL cholesterol must be studied during antihypertensive therapy and if there is a marked and confirmed deterioration towards an "increased atherogenicity", it is reasonable to envision a change of the antihypertensive agent. With the some efficacy on blood pressure levels and general tolerance, the choice should favour drugs having the least unfavourable effects on lipoprotein metabolism.