The clinical significance of the extent of a decrease in nocturnal blood pressure (BP) and the resulting classification of hypertensives as "dipper" (decrease in BP >10% day BP) or "nondipper" (decrease in BP <10% day BP) has been questioned recently. The aim of our study was to evaluate if the extent of a nocturnal BP decrease, established on the basis of a single 24-hour BP monitoring, is related to cardiovascular remodeling in essential hypertension. We enrolled 253 never-treated essential hypertensives (24-hour BP > or = 140 and/or 90 mm Hg); for each patient we recorded 24-hour BP, left ventricular (LV) echocardiogram, Doppler transmitral flow velocities, and carotid-femoral pulse-wave velocities. A dipper BP profile was found in 161 patients, whereas 92 patients were nondippers. The 2 groups did not differ with regard to age, gender, body mass index, 24-hour and daytime BP, and 24-hour, daytime, and nighttime heart rate. All LV morphologic characteristics LV systolic and diastolic functional parameters, mitral Doppler-derived diastolic indexes, as well as carotid-femoral pulse-wave velocity, and aortic index distensibility were not significantly different between dippers and nondippers. The prevalence of LV hypertrophy and diastolic dysfunction was also similar between the 2 groups. The extent of a decrease in nocturnal BP did not correlate with any cardiovascular parameter. In conclusion, in never-treated hypertensives, the extent of a nocturnal BP decrease is not related to LV morpho-functional characteristics and aortic distensibility; therefore, the nondipping status established on the basis of a single 24-hour BP monitoring does not identify hypertensive patients with greater cardiovascular damage.