Gender, day-night blood pressure changes, and left ventricular mass in essential hypertension. Dippers and peakers.

The finding of increased left ventricular (LV) mass in hypertensive subjects with blunted nocturnal fall in blood pressure (BP) might be an artifact of matching patients for daytime BP, with resulting higher 24-h BP in nondippers. Therefore, we compared a large number (n = 1048) of hypertensive dippers and nondippers in their LV mass at echocardiography before and after adjustment for 24-h, daytime, and nighttime ambulatory BP. In men, the difference between dippers and nondippers was not significant before and after adjustment for 24-h BP, but after adjustment for nighttime BP LV mass was greater in dippers (more properly "peakers"). In women, LV mass was greater in nondippers than in dippers both before and after adjustment for 24-h BP, while the difference between the two groups disappeared after adjustment for nighttime BP. Thus, for any given level of mean 24-h BP, a flattened diurnal BP profile is associated with a greater LV mass in hypertensive women. Daytime hypertension, either associated or not with a blunted nocturnal fall in BP, may be a sufficient determinant of LV wall thickening in men.