title: Cough in the elderly population: relationships with multiple comorbidity.
abstract: BACKGROUND
  The epidemiology of cough in the elderly population has not been studied comprehensively. The present study aimed to investigate the epidemiology of cough in a community elderly population, particularly in relation with their comorbidity.
  
  
  METHODS
  A cross-sectional analysis was performed using a baseline dataset from the Korean Longitudinal Study on Health and Aging, a community-based elderly population cohort study. Three types of cough (frequent cough, chronic persistent cough, and nocturnal cough) were defined using questionnaires. Comorbidity was examined using a structured questionnaire. Health-related quality of life was assessed using the Short Form 36 questionnaire.
  
  
  RESULTS
  The prevalence was 9.3% for frequent cough, 4.6% for chronic persistent cough, and 7.3% for nocturnal cough. In multivariate logistic regression analyses, smoking, asthma and allergic rhinitis were found to be risk factors for cough in the elderly. Interestingly, among comorbidities, constipation and uncontrolled diabetes mellitus (HbA1c ≥ 8%) were also found to have positive associations with elderly cough. In the Short Form 36 scores, chronic persistent cough was independently related to impairment of quality of life, predominantly in the mental component.
  
  
  CONCLUSIONS
  Cough has a high prevalence and is detrimental to quality of life in the elderly. Associations with smoking, asthma and rhinitis confirmed previous findings in younger populations. Previously unrecognised relationships with constipation and uncontrolled diabetes mellitus suggested the multi-faceted nature of cough in the elderly.
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea ; Institute of Allergy and Clinical Immunology, Seoul National University Medical Research Center, Seoul, Korea.
authors.forename: Woo-Jung
authors.initials: WJ
authors.lastname: Song
authors.forename: Alyn H
authors.initials: AH
authors.lastname: Morice
authors.forename: Min-Hye
authors.initials: MH
authors.lastname: Kim
authors.forename: Seung-Eun
authors.initials: SE
authors.lastname: Lee
authors.forename: Eun-Jung
authors.initials: EJ
authors.lastname: Jo
authors.forename: Sang-Min
authors.initials: SM
authors.lastname: Lee
authors.forename: Ji-Won
authors.initials: JW
authors.lastname: Han
authors.forename: Tae Hui
authors.initials: TH
authors.lastname: Kim
authors.forename: Sae-Hoon
authors.initials: SH
authors.lastname: Kim
authors.forename: Hak-Chul
authors.initials: HC
authors.lastname: Jang
authors.forename: Ki Woong
authors.initials: KW
authors.lastname: Kim
authors.forename: Sang-Heon
authors.initials: SH
authors.lastname: Cho
authors.forename: Kyung-Up
authors.initials: KU
authors.lastname: Min
authors.forename: Yoon-Seok
authors.initials: YS
authors.lastname: Chang
mesh_terms: D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D003371:Cough / Q000150:complications / Q000453:epidemiology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D015995:Prevalence