White-Coat Hypertension Without Organ Damage: Impact on Long-Term Mortality, New Hypertension, and New Organ Damage

BACKGROUND: According to some guidelines, white-coat hypertension (WCH) carries little or no increase of cardiovascular risk in the absence of organ damage (OD), but no data are available on this issue. METHODS: Using the population data from PAMELA (Pressioni Arteriose Monitorate E Loro Associazioni), we evaluated cardiovascular and total mortality over a median follow-up of 29 years in WCH (elevated office and normal 24-hour or home blood pressure [BP]) and normotensive controls (normal in- and out-of-office blood pressure) with no echocardiographic left ventricular hypertrophy and no reduction of estimated glomerular filtration rate. Patients with sustained hypertension (SH, in- and out-of-office blood pressure elevation) and normotensive, WCH, and SH with cardiac and renal OD served as controls. RESULTS: In the 1423 subjects analyzed, there were 165 cardiovascular and 526 all-cause deaths. After adjustment for confounders, no-OD WCH exhibited a risk of fatal cardiovascular events lower than that of no-OD SH but greater than that of no-ODN (hazard ratio, 2.0 [95% CI, 1.1–3.6], P=0.02), this being the case also for all-cause mortality. Compared with no-OD normotensive, no-OD WCH also exhibited a greater 10-year adjusted risk to develop new SH or OD. Similar findings were obtained in normotensive, WCH, and SH with OD. CONCLUSIONS: The present study provides the first evidence that WCH with no OD is accompanied by a noticeable increase in long-term risk of mortality, new hypertension, and new OD, thereby differing from normotension.