Effect of weight loss on blood pressure and drug consumption in normal weight patients

The effect of weight loss on blood pressure and on antihypertensive drug consumption was examined in 81 nonobese subjects with essential hypertension who had been chronically treated with antihypertensive drugs. A hypocaloric diet was prescribed for 5 months. A weight loss greater than 2 kg in 5 months was considered significant. Quality and quantity of antihypertensive medications were scored according to a formula. In the subjects whose medication and weight did not change, mean arterial pressure remained unchanged, whereas it decreased significantly (-7.1 ± 1.9 mm Hg) in those who showed significant weight loss (— 3.28 ± 0.34 kg) with no change in medication. Among the subjects whose antihypertensive medication remained constant during the diet program there was a significant correlation between the change in weight and mean arterial pressure (r = 0.45, p < 0.01). Mean arterial pressure increased significantly (+ 5.1 ± 1.7 mm Hg) in subjects whose weight remained unchanged with a decrease in medication, whereas it remained significantly lower than the control (by-3.1 ± 2.0 mm Hg) in those whose weight decreased significantly (-4.57 ± 0.69 kg) with the decrease in medication. The weight loss-induced decrease in blood pressure occurred independently of the initial degree of obesity and the initial level of mean arterial pressure. Urinary sodium excretion in the control period and at the end of the diet program did not differ significantly between subgroups. These results indicate that, even in subjects of normal weight with essential hypertension, weight loss can induce a fall in blood pressure that leads to a reduction of antihypertensive medication. A 4-kg weight loss was equivalent to the amount of antihypertensive medication required for effective control of mild hypertension.