Acetaminophen use and change in blood pressure in a hypertensive population.

OBJECTIVE: Recent data suggest that self-reported acetaminophen use is associated with increased risk of cardiovascular events and a rise in arterial blood pressure (BP). We investigated the association between acetaminophen use and BP in a large cohort of patients with hypertension using verified prescription data.
METHODS: We extracted data from the UK General Practice Research Database for all hypertensive patients aged 65 years or older who were prescribed acetaminophen and had BP measured both before and during acetaminophen treatment. Patients were grouped according to whether their antihypertensive treatment remained unchanged or not during the study period. The change in SBP and DBP during acetaminophen use was determined and compared with the change in BP in a group of nonacetaminophen-exposed people identified using propensity matching.
RESULTS: A total of 2754 acetaminophen-exposed individuals were included. BP rose slightly during the period of acetaminophen treatment wherein antihypertensive treatment was unchanged [change in SBP 1.6 [95% confidence interval (CI) 0.7-2.5) mmHg and change in DBP 0.5 (95% CI 0.1-1.0) mmHg)]. BP fell when new antihypertensive medications were prescribed. These BP changes were no different to those seen in matched nonacetaminophen-exposed individuals [between-group difference wherein antihypertensive treatment was unchanged was 0.6 (95% CI -0.6 to 1.9) mmHg and 0.5 (-0.1 to 1.1) mmHg for change in SBP and DBP, respectively].
CONCLUSION: We found no evidence of a sustained rise in blood pressure caused by acetaminophen treatment in a large population of patients with treated hypertension.