title: Risk of atrial fibrillation in dipper and nondipper sustained hypertensive patients.
abstract: OBJECTIVE
  The risk of atrial fibrillation (AF) in sustained hypertensive patients with different circadian blood pressure (BP) patterns is unknown. We investigated the risk of new onset AF in dipper and nondipper sustained hypertensive patients.
  
  
  METHODS
  The occurrence of AF was evaluated in 1141 patients aged > or = 40 years with sustained hypertension (clinic BP > or = 140 and/or 90 mmHg and daytime BP > or = 135 and/or 85 mmHg). Among these patients, 783 had night-time systolic BP fall > or = 10% (dippers) and 358 had night-time BP decline <10% (nondippers).
  
  
  RESULTS
  During the follow-up (6.1+/-3.2, range 0.5-12.9 years), AF occurred in 43 patients. The AF rate per 100 patient-years in dippers and nondippers was 0.38 and 1.13, respectively. AF free survival was significantly different between the groups (P=0.0002). After adjustment for other covariates, including left atrial enlargement or left ventricular hypertrophy (these variables were analyzed in separate models because of a strong association between them) and 24-h BP, Cox regression analysis showed that the risk of AF was significantly higher in nondippers than in dippers [nondippers vs. dippers, relative risk (RR) 2.02, 95% confidence interval (CI) 1.08-3.79, P=0.028 in the model including left atrial enlargement, and RR 1.97, 95% CI: 1.05-3.69, P=0.035 in the model including left ventricular hypertrophy].
  
  
  CONCLUSIONS
  This study shows that nondipper sustained hypertensive patients have a two-fold greater risk of developing AF than dipper ones. This aspect could partly contribute to explain the higher cardiovascular risk previously observed in nondipper hypertensive patients.
authors.affiliation: Department of Medicine and Aging Science, University Gabriele d'Annunzio, and Clinical Research Center, University Gabriele d'Annunzio Foundation, Chieti, Italy. pierdomenico@unich.it
authors.forename: Sante D
authors.initials: SD
authors.lastname: Pierdomenico
authors.forename: Domenico
authors.initials: D
authors.lastname: Lapenna
authors.forename: Franco
authors.initials: F
authors.lastname: Cuccurullo
mesh_terms: D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation / Q000209:etiology / Q000401:mortality*; D002940:Circadian Rhythm; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000401:mortality*; D017379:Hypertrophy, Left Ventricular / Q000209:etiology / Q000401:mortality; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D015996:Survival Rate