title: Combined effects of cognitive impairment and hypertension on total mortality in elderly people: the Kangwha Cohort study.
abstract: BACKGROUND
  Previous studies have shown links between cognitive impairment and hypertension as well as mortality. However, combined effects of these two conditions on mortality have not been fully explored.
  
  
  OBJECTIVE
  To assess the combined effect of cognitive impairment and hypertension on all-cause mortality among the elderly people.
  
  
  METHODS
  We followed a cohort of 2,496 residents in Kangwha County, ranging in age from 64 to 101 years as of March 1994, for all-cause mortality for 11.8 years up to December 31, 2005. We calculated hazard ratios (HR) for all-cause mortality by cognitive status and blood pressure using the Cox proportional hazards model after having controlled for confounding factors.
  
  
  RESULTS
  1,189 people (47.6%) died during the 11.8 years of follow-up. The HR associated with severe cognitive impairment increased from 2.15 (95% CI: 1.30, 3.54) for prehypertension over 2.68 (95% CI: 1.60, 4.48) for stage 1 hypertension to 3.60 (95% CI: 1.99, 6.49) for stage 2 hypertension in women. A mortality risk of 3.67 (95% CI: 2.05, 6.57) was observed among men who had both mild cognitive impairment and stage 2 hypertension.
  
  
  CONCLUSIONS
  Individuals with coexisting cognitive impairment and hypertension are at an increased risk of all-cause mortality compared with those with cognitive impairment or hypertension alone.
authors.affiliation: Department of Public Health, Graduate School, College of Medicine, Yonsei University, Seoul, Korea.
authors.forename: Bayasgalan
authors.initials: B
authors.lastname: Gombojav
authors.forename: Sang-Wook
authors.initials: SW
authors.lastname: Yi
authors.forename: Jae Woong
authors.initials: JW
authors.lastname: Sull
authors.forename: Chung Mo
authors.initials: CM
authors.lastname: Nam
authors.forename: Heechoul
authors.initials: H
authors.lastname: Ohrr
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001794:Blood Pressure; D003072:Cognition Disorders / Q000150:complications* / Q000453:epidemiology / Q000401:mortality* / Q000523:psychology; D060825:Cognitive Dysfunction / Q000150:complications / Q000453:epidemiology / Q000401:mortality; D015331:Cohort Studies; D015897:Comorbidity; D003625:Data Collection; D005260:Female; D006801:Humans; D006973:Hypertension / Q000150:complications* / Q000453:epidemiology / Q000401:mortality* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D056910:Republic of Korea / Q000453:epidemiology; D012307:Risk Factors