DIETARY SALT REDUCTION POTENTIATES THE ACTION OF HYPOTENSIVE DRUGS

Hypertension is a common health problem. Hypotensive drugs and low salt diet are used in its treatment. This study was designed to compare the effectiveness of a low-salt diet and drug therapy in the treatment of arterial hypertension. A total of 256 randomly selected patients with essential hypertension consulting the Non-contagious Diseases Clinic in Shahreza, Isfahan, Iran, were included in the study for a period of 28 days. They were divided into four groups. Groups A and B received both methyldopa (250 mg t.i.d.) and hydrochlorothiazide (daily 10 mg), the former consuming a normal and the second a low-salt diet. Groups C and D consumed a low-salt and a salt-free diet, respectively, with no drugs. Both treatments A and B caused statistically significant reductions in blood pressure even after seven days, but treatment B was much more effective. Reductions in blood pressure in Groups C and D were very little, even after 28 days. Using the three-way classification of analysis of variance, it was revealed that interactions existed among the three factors, i.e., age, diet and length of treatment, as regards lowering blood pressure. We conclude, confirming previous reports in the literature, that a low-salt diet potentiates the hypotensive action of antihypertensive drugs.