Primary Prevention With Metoprolol in Patients With Hypertension-Reply

In Reply.—  The protocol for the trial of β-blockers vs diuretics in hypertension was defined in 1975. All centers randomized patients either to metoprolol or a diuretic counterpart, with the exception of one center with 46 patients taking propranolol (atenolol was not included as an option in the original study). More than two years after the first patient was randomized, a separate part randomizing patients to atenolol or diuretics was started (Fig 2). Many patients were followed up for only one year in this part, partially explaining a low mortality rate, probably about six deaths per 1000 patient-years in the diuretic-treated group. That tendencies in one or the other direction may occur when mortality rates are low, as in the part comparing atenolol with diuretics, might be expected by chance. This does not change the interpretation of the results of the MAPHY Study since, as pointed out by the chairman