The combination of a low-Na/high-K salt with metoprolol in the treatment of mild-moderate hypertension. A multicenter study.

To extend our previous findings that a low-Na/high-K salt (S) reduces BP in hospitalized patients, a multicenter study was performed. After a placebo period during which patients were informed by written instruction how to avoid only foods with a high Na content, 143 out-patients (84 males and 59 females, mean age 50.7 years, range 28-69) with DBP greater than or equal to 95 mm Hg randomly received for 4 weeks either metoprolol (M) 200 mg SR qd (67 patients), or S, 2 g bid to add to foods (76 patients). At the end of this period patients with DBP still greater than 90 mm Hg combined the two treatments for a further 4 weeks. Mean blood pressure (mm Hg), HR (bpm), 24-hrs urinary Na and K excretion were measured fortnightly. In comparison to pretreatment values MBP was significantly (P less than 0.01) reduced by both treatments, although to a greater extent in the M group already at the second week, without any further decrement thereafter. In the S group MBP decreased by 4.4 mm Hg and 27/76 patients were responders (DBP less than or equal to 90 mm Hg), while in the M group it was reduced by 9.0 mm Hg and 28/67 patients were responders. In the S group urinary Na excretion was significantly (P less than 0.01) lower than in the M group, and this difference was present until the end of period 1.(ABSTRACT TRUNCATED AT 250 WORDS)