Should all patients with mild hypertension be treated?

By Jane Lewis
A UK longitudinal cohort study has found no evidence to support guideline recom­mendations that treatment should be initiated in patients with low­risk mild hypertension.

Writing in JAMA Internal Medicine, the study authors said new guidelines from the American College of Cardiology/American Heart Association (ACC/AHA) recommending initiation of pharmacological treatment for all patients with a blood pressure of 140/90 mmHg or higher regardless of risk were controversial, particularly in terms of treating those with low­-risk mild hypertension. They advised that doctors ‘be cautious when initiating new treatment in this population, and patients should be made aware of the limited evidence of efficacy for treatment in low­-risk individuals.’

Cardiologist Professor Terry Campbell, Director of Research at St Vincent’s Hospital, Sydney, told Medicine Today the study was a timely reminder always to bear in mind the old adage ‘first do no harm’ when treating patients.

‘While there is epidemiolo­gical evidence to support the expectation of reduced risk of CVD at ever lower levels of blood pressure, the law of diminishing returns also applies here,’ he said. ‘The more we use drugs to reduce CVD risk in patients who are already at very low absolute risk, the more we risk doing more harm than good.’

The study examined the electronic records of patients aged 18 to 74 years (mean, 54.7 years) with mild hyperten­sion (untreated blood pressure 140/90 to 159/99mmHg) and matched 19,143 patients who were treated within 12 months of diagnosis to an equal number of untreated patients. Over a median follow up of 5.8 years, no evidence was found of an association between anti­ hypertensive treatment and mortality (hazard ratio [HR], 1.02) or between antihyper­tensive treatment and CVD (HR, 1.09). Treatment was associated with an increased risk of adverse events, including hypotension, syncope, electrolyte abnormalities and acute kidney injury.

‘Decisions to treat reversible risk factors such as blood pressure and lipids should be based on the overall absolute risk of the patient and not just on their blood pressure reading or LDL­-cholesterol level,’ said Professor Campbell. ‘What stands to be gained, in terms of reduced CVD risk, needs to be weighed against potential side effects of the drugs used, and an individual­ised decision made.’
JAMA Intern Med 2018; doi: 10.1001/jamainternmed.2018.4684.