['It has been reported that aspirin (ASA) may interfere with the blood pressure (BP)-lowering effect of various antihypertensive agents and attenuate the beneficial effects of angiotensin-converting enzyme (ACE) inhibitors in patients with congestive heart failure.', 'Data from the Hypertension Optimal Treatment (HOT) Study, in which 18 790 intensively treated hypertensive patients were randomized to either ASA 75 mg daily or placebo for 3.8 years (with a 15% reduction in cardiovascular events and a 36% reduction in myocardial infarction in ASA-treated patients), were reanalysed for the whole group of patients and for various subgroups with particular attention to the possible effects of ASA on BP and renal function. In ASA-treated and placebo-treated patients: (1) systolic blood pressure (SBP) and diastolic blood pressure (DBP) values achieved with antihypertensive treatment were superimposable, with clinically irrelevant differences; (2) these superimposable SBP and DBP were achieved with antihypertensive therapies, that were quantitatively and qualitatively similar, and (3) changes in serum creatinine and in estimated creatinine clearance and the number of patients developing renal dysfunction were also similar. Furthermore, the cardiovascular benefits of ASA were of the same magnitude in hypertensive patients receiving or not receiving ACE-inhibitors.'] Does low-dose aspirin interfere with the blood pressure-lowering effects of antihypertensive therapy?