EFFECTIVENESS OF NIFEDIPINE GASTROINTESTINAL THERAPEUTIC SYSTEM FOR TREATMENT OF HYPERTENSION - RESULTS OF THE MATH TRIAL

Nifedipine gastrointestinal therapeutic system (GITS), a controlled-release delivery system given once a day, was evaluated in a multisite study of mild-to-moderate hypertensive subjects, seated diastolic pressure between 95 and 110 mm Hg, on placebo. Of 1,666 subjects enrolled, 69% were eligible to begin treatment. Therapy with nifedipine GITS was started at 30 mg daily and increased by 30 mg/day each week until there was a response (seated diastolic pressure < 90 mm Hg and a reduction of greater-than-or-equal-to 10 mm Hg) or until a maximum dose of 180 mg/day was reached. After titration, responders were kept on active treatment for 12 more weeks. Seventy-six percent of those treated responded, and 88% of the responders completed the 12-week phase. Comparisons were made among relevant subgroups. Elderly patients (age greater-than-or-equal-to 65 years) had a significantly higher response rate at a lower average daily dose, compared with younger subjects. Response rates were > 70% and relatively similar in (a) white and black patients, (b) diabetic and nondiabetic patients, (c) men and women, and (d) normal-weight, overweight, and obese patients. Nifedipine GITS had no significant effect on fasting serum glucose or cholesterol fractions. Edema and headache were the most often observed adverse effects during treatment. Incidence of the former was related to dose but occurred without evidence of fluid retention (average body weight fell significantly by 1% during treatment). As antihypertensive monotherapy given once a day, nifedipine GITS is effective and well tolerated for a wide spectrum of hypertensive patients.