Sibutramine Lowers Blood Pressure in High-Risk Patients

Sibutramine (Meridia) is a serotonin and norepinephrine reuptake inhibitor (SNRI) licensed as a prescription drug for obesity treatment.

Although sibutramine has been available for around a decade in over 70 countries and has been shown to reduce weight and improve comorbidities and risk factors in patients with obesity, its potential to increase blood pressure in some patients has remained an important barrier to its widespread use.

In the most recent issue of Diabetes Obesity and Metabolism, together with other colleagues from the Executive Steering Committee, we now publish an analysis of blood pressure changes associated with sibutramine during the 6-week lead-in period of the sibutramine cardiovascular outcomes trial (SCOUT), an ongoing, double-blind, randomized, placebo-controlled trial in over 10,000 overweight/obese patients at high risk of a cardiovascular event.

During the 6-week lead-in period, 10,742 patients received sibutramine and weight management. At entry, approximately 50% of patients were hypertensive and 26% were high-normal.

In hypertensive patients, blood pressure decreased by median of -6.5 mmHg systolic and -2.0 mmHg diastolic (p < 0.001). Even hypertensive patients with no weight loss or with weight gain had median decreases of -3.5 mmHg systolic and -1.5 mmHg diastolic (p < 0.001). Approximately 43% of patients initially categorized as hypertensive had a lower blood pressure category at end-point.

On the other hand, normotensive patients had median increases of 1.5 mmHg systolic and 1.0 mmHg diastolic (p < 0.001) which was attenuated with increasing weight loss.

As expected, pulse rates were uniformly elevated (median 1-4 bpm, p < 0.001) across blood pressure and weight change categories.

Although it must be remembered, that all patients received sibutramine during the lead-in period and therefore some decrease in blood pressure may be due to regression to the mean, the data confirm that even in patients at high risk for cardiovascular events, the vast majority of patients (especially if hypertensive) will experience a reduction in blood pressure.

Whether or not treatment with sibutramine will also reduce cardiovascular mortality of course remains to be seen when the study finishes sometime next year.

In the meantime, these data reinforce the notion that sibutramine can indeed be used in the vast majority of patients with controlled hypertension without having to fear an increase in blood pressure.

Obviously, in the few patients who do happen to experience an increase in blood pressure, adjustments in antihypertensive medications or discontinuation of sibutramine should be considered.

Edmonton, Alberta

Conflict of Interest: I am on the Executive Steering Committee of the SCOUT trial and am reimbursed for my time and effort by Abbott Laboratories, the maker of sibutramine