Variability in plasma lipoprotein profiles when comparing diltiazem and propranolol

OBJECTIVE: To examine the effects of diltiazem and propranolol on plasma lipoproteins in a double-blind, comparative trial. PATIENTS: Twenty-one mild-to-moderate hypertensive patients. METHODS: Following discontinuation of previous antihypertensive treatments, and a 4-week, single-blind, placebo run-in, subjects were randomized to receive sustained-release diltiazem or propranolol. Total cholesterol, high-density lipoproteins (HDL), low-density lipoproteins (LDL), and very-low-density lipoproteins (VLDL) were measured during placebo administration and after 12-16 weeks of treatment. RESULTS: No significant changes in plasma lipoprotein concentrations were noted in either the diltiazem or propranolol group compared with baseline values or each other. Marked variation in HDL, LDL, and VLDL were noted following drug treatment and in eight subjects whose lipoprotein concentrations were remeasured prior to drug treatment during the placebo period. The alterations were bidirectional, and similar in magnitude to those found following drug treatment. CONCLUSIONS: In many cases, changes in plasma lipoproteins reported to be a consequence of antihypertensive treatment may merely reflect normal intrapatient variability.