| 119 CUSPIDI et al. diagnosis of office hypertension or evaluate the efficacy of antihypertensive therapy. A total of 7364 individual 24-hour ambulatory BP recordings from untreated individuals and treated hypertensive patients with office systolic BP ≥ 140 mm Hg and/or diastolic BP ≥ 90 mm Hg were analyzed. Based on office and 24-hour ambulatory BP values, subjects were divided into four groups: (a) untreated elevated office systolic or diastolic BP and normal 24-hour ambulatory BP, that is, WCH; (b) untreated elevated office systolic or diastolic BP and elevated 24-hour ambulatory BP, that is, sustained hypertension; (c) treated elevated office systolic or diastolic BP and normal 24-hour ambulatory BP (<130/80 mm Hg), that is, WUCH; and (d) treated elevated office and 24-hour systolic or diastolic BP, that is, uncontrolled hypertension. The prevalence rates WCH and WUCH were assessed according to both European and American hypertension guidelines whose normal 24-hour BP thresholds are <130/80 and 125/75 mm Hg, respectively. A total of 1284 patients were classified as WCH (17.4%) and 1950 as WUCH (26.5%) according to the 2018 ESH/ESC guidelines; the corresponding numbers, based on the 2017 AHA/ACCguidelines, were 697 (9.4%) and 1156 (15.6%), respectively. These findings strongly suggest that the detection of both WCH and WUCH markedly decreases when applying the AHA/ACC 24-hour BP thresholds and, at the same time, an opposite trend occurs for the sum of sustained untreated and uncontrolled hypertension (from 56% to 75%). However, it should not be ignored that the classification of BP patterns has limited reproducibility over time.As for WUCH, a recent comprehensive analysis of the European Lacidipine Study on Atherosclerosis showed that its reproducibility was worse than that of patients showing control or lack of control of both office and ambulatory BP. 9 Whether the use of lower 24-hour BP criteria for defining WCH and WUCH can improve cardiovascular risk stratification and preventive strategies in the hypertensive population remains an open question. Data from the Intensive Versus Standard Ambulatory Blood Pressure Lowering to Prevent Functional Decline In the Elderly (INFINITY) study in which intensive treatment of ambulatory BP in older patients was well tolerated and associated with a significant reduction of cardiovascular can be considered an argument in favor of lower ambulatory normality thresholds. 10