Reverse Dipper and High Night-time Heart Rate in Acute Stage of Cerebral Infarction Are Associated with Increased Mortality

Abstract

Reverse dipper, blood pressure (BP) rises during night-time, is a risk factor of increased cardiovascular events in hypertensive patients. However, we have little information whether reverse dipper in acute stage of cerebral infarction (CI) affects on the recurrence and mortality. We studied to assess the relationship between reverse dipper and adverse clinical outcomes in the acute stage of CI. We screened and enrolled consecutive patients with acute CI with ambulatory blood pressure monitoring (ABPM) within 2weeks after admission from August 2001 to July 2005. According to systolic blood pressure (SBP) dropping pattern during night-time compared with daytime, we classified into extreme dipper (≥20%), dipper (≥10%, <20%), nondipper (≥0%, <10%), and reverse dipper (BP rises during night-time). We analyzed 426 patients (72±13years old, 255 men) and checked recurrence of CI or all-cause mortality for further 7.6±3.1years for checking of recurrence or all-cause mortality. Of 426 patients, 202 patients were nondippers (47%), 134 were reverse dippers (32%), 80 were dippers (19%), and 10 were extreme dippers (2%). During the follow-up period, 89 patients (21%) had recurrence of CI. After multivariate analysis, daytime SBP (hazard ratio=1.014, P=.018) was the significant predictor of recurrence. There were 141 deaths (33%) in our study cohort. Multivariate analysis showed that age (hazard ratio=1.106, P<.001), nocturnal mean heart rate (hazard ratio=1.023, P=.004), and reverse dipper (hazard ratio=1. 676, P=.007) were statistically significant. Reverse dipper and high night-time heart rate in the acute stage of CI were associated with total mortality during long-term follow-up. These findings suggest the clinical utility of ABPM in acute stage of CI.