Antihypertensive therapy potentially unnecessary in low risk, mild hypertension
Patients with mild hypertension who are at low risk for cardiovascular disease (CVD) do not appear to derive mortality or CVD benefit from antihypertensive treatments, raising questions on the need for treatment in this population, according to a recent study from England.
Researchers used data from the Clinical Practice Research Datalink between January 1998 and September 2015 to identify adults with mild, untreated hypertension (three consecutive measurements of blood pressure [BP] 140/90 to 159/99 mm Hg over 12 months; mean pre-treatment BP 146/89 mm Hg) and no history or risk factors for CVD. Patients who received antihypertensive treatment (n=19,143, mean age 54.7 years, 55.9 percent female) were matched with those who did not receive treatment (n=19,143, mean age 54.9 years, 55.5 percent female), and were followed up for a median 5.8 years. Among patients in the untreated group, 41.6 percent received an antihypertensive during the follow-up period.
Patients who received antihypertensive treatment did not differ from those who did not receive treatment in terms of mortality (4.49 percent vs 4.08 percent, hazard ratio [HR], 1.02, 95 percent confidence interval [CI], 0.88–1.17; p=0.81) or CVD (HR, 1.09, 95 percent CI, 0.95–1.25; p=0.23). [JAMA Intern Med 2018;doi:10.1001/jamainternmed.2018.4684]
Conversely, patients who received treatment had elevated risks of hypotension (HR, 1.69, 95 percent CI, 1.30–2.20; p<0.001), syncope (HR, 1.28, 95 percent CI, 1.10–1.50; p=0.002), acute kidney injury (HR, 1.37, 95 percent CI, 1.00–1.88; p=0.048), and electrolyte abnormalities (HR, 1.72, 95 percent CI, 1.12–2.65; p=0.01).
Subgroup analysis showed that the effect of antihypertensive treatment on mortality or CVD did not differ by age, systolic BP, or antihypertensive drug class.
Recent guidelines from the ACC/AHA* recommended antihypertensive treatment initiation in high-risk patients with BP ≥130/80 mm Hg, as well as in those with BP ≥140/90 mm Hg regardless of risk, said the researchers. [J Am Coll Cardiol 2017;doi:10.1016/j.jacc.2017.11.006]
“These recommendations are considered to be controversial particularly with regard to treatment of people with low CVD risk and mild hypertension (ie, sustained blood pressure of 140/90–159/99 mm Hg), for whom there is a lack of clinical trial evidence to support initiation of pharmacologic treatment,” they said.
“We found that, contrary to the latest guideline recommendations, there was no evidence of any benefit to treating patients with low-risk mild hypertension,” said study first author Dr James Sheppard from the Nuffield Department of Primary Care Health Science, University of Oxford, Oxford, UK.
“This suggests that doctors should be cautious when considering hypertension treatment in this group and we would therefore encourage a conversation between a patient and their doctor to decide the best way to treat the condition. Younger patients in particular may prefer to adopt lifestyle changes to reduce their BP, rather than committing to taking antihypertensive drugs for many years,” he said.
“Given that we found tangible evidence of the potential harm of treating people with mild hypertension, and no evidence of benefit, this study does raise questions over the value of initiating drug treatment in such patients,” added study co-author Professor Jonathan Mant, head of the Primary Care Unit at the University of Cambridge, Cambridge, UK.
The researchers acknowledged the potential for confounding in this observational study. Furthermore, it is not known if longer follow-up would have yielded different findings or if patients were adherent to antihypertensive therapy.
“To ensure future guideline recommendations for treating low-risk mild hypertension are based on the best-quality evidence, large-scale clinical trials are now needed,” said Sheppard.