title: Prognostic values of bundle branch blocks for cardiovascular mortality in Japanese (24year follow-up of NIPPON DATA80).
abstract: OBJECTIVE
  Left bundle branch block (LBBB) is generally considered to be associated with a poorer prognosis in comparison with normal controls. However, there are some studies that showed no difference in prognosis of LBBB in comparison with normal controls.
  
  
  RESULTS
  We studied prognostic values of BBBs on cardiovascular disease (CVD) and total mortality using the NIPPON DATA80 database with a 24-year follow-up. At the baseline in 1980, data were collected on study participants, ages 30years and over, from randomly selected areas in Japan. We followed 9,090 participants (44% men, mean age 51). During the 24year follow-up, there were 886 CVD, and 2,597 total mortality cases. Among participants, 0.2% of them were in LBBB, 1.3% in RBBB, 4.3% in other ventricular conduction defect (VCD) groups. The multivariate-adjusted hazard ratio (HR) using the Cox model including biochemical and other ECG variables revealed that LBBB was significantly positively associated with CVD (HR=2.71, 95% confidence intervals [CI]: 1.35-5.45, P=0.005), and total (HR=2.07, 95%CI: 1.26-3.39, P=0.004) mortality in men and women combined compared to participants without VCD. RBBB and other VCDs did not carry any significant risk for CVD or total mortality.
  
  
  CONCLUSIONS
  We found significant positive associations of LBBB with CVD and total mortality independent of confounding factors including other ECG changes.
authors.affiliation: Cardiovascular Epidemiology, Kyoto Women's University, Kyoto, Japan. nakamury@kyoto-wu.ac.jp
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Nakamura
authors.forename: Tomonori
authors.initials: T
authors.lastname: Okamura
authors.forename: Taku
authors.initials: T
authors.lastname: Inohara
authors.forename: Shun
authors.initials: S
authors.lastname: Kohsaka
authors.forename: Makoto
authors.initials: M
authors.lastname: Watanabe
authors.forename: Aya
authors.initials: A
authors.lastname: Higashiyama
authors.forename: Aya
authors.initials: A
authors.lastname: Kadota
authors.forename: Nagako
authors.initials: N
authors.lastname: Okuda
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Ohkubo
authors.forename: Shin-ya
authors.initials: SY
authors.lastname: Nagasawa
authors.forename: Katsuyuki
authors.initials: K
authors.lastname: Miura
authors.forename: Akira
authors.initials: A
authors.lastname: Okayama
authors.forename: Hirotsugu
authors.initials: H
authors.lastname: Ueshima
mesh_terms: D000368:Aged; D002037:Bundle-Branch Block / Q000175:diagnosis* / Q000401:mortality*; D002318:Cardiovascular Diseases / Q000175:diagnosis* / Q000401:mortality*; D015897:Comorbidity; D016757:Death, Sudden, Cardiac / Q000453:epidemiology*; D004562:Electrocardiography / Q000706:statistics & numerical data*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D015996:Survival Rate