A recent retrospective study raises questions about routine use of antihypertensive treatment for patients with mild, low-risk hypertension.
Researchers conducted a retrospective, longitudinal cohort study of data from the Clinical Practice Research Datalink from Jan. 1, 1998, through Sept. 30, 2015, using the electronic health records of 38,286 low-risk adult patients who had mild hypertension. Low-risk was defined as excluding anyone with a history of cardiovascular disease, left ventricular hypertrophy, atrial fibrillation, diabetes, chronic kidney disease, or family history of premature heart disease, and mild hypertension was defined as untreated blood pressure of 140/90 to 159/99 mm Hg. Results were published online Oct. 29 in JAMA Internal Medicine.
There were 19,143 patients who received hypertension treatment, matched 1:1 with similar untreated patients for a median follow-up of 5.8 years. No evidence of an association was seen between antihypertensive treatment and mortality (hazard ratio [HR], 1.02; 95% CI, 0.88 to 1.17) or between antihypertensive treatment and cardiovascular disease (HR, 1.09; 95% CI, 0.95 to 1.25). However, treatment was associated with an increased risk of adverse events, including hypotension (HR, 1.69; 95% CI, 1.30 to 2.20; number needed to harm at 10 years [NNH10], 41), syncope (HR, 1.28; 95% CI, 1.10 to 1.50; NNH10, 35), electrolyte abnormalities (HR, 1.72; 95% CI, 1.12 to 2.65; NNH10, 111), and acute kidney injury (HR, 1.37; 95% CI, 1.00 to 1.88; NNH10, 91).
The increased risk of adverse events means that physicians should exercise caution when following guidelines that generalize findings from trials conducted in high-risk individuals to those at lower risk, the authors noted.
“This finding does not seem particularly important in terms of number needed to harm but, in the context of little evidence of benefit, suggests that physicians should be cautious when initiating new treatment in this population, particularly because such an approach may affect millions of individuals,” the authors wrote.