title: Smoking and cognitive impairment among older persons in Malaysia.
abstract: BACKGROUND
  Previous studies have shown conflicting results on the association between smoking and cognitive function. This study aims to examine the relationship of smoking with cognitive function.
  
  
  METHODS
  Data for the study, consisting of 2553 older adults aged 60 years and older, were drawn from a nationwide household survey entitled "Determinants of Wellness among Older Malaysians: A Health Promotion Perspective" conducted in 2010.
  
  
  RESULTS
  Current smokers had lower rates of cognitive impairment compared to never smokers (17.4% vs 25.9%), while cognitive function in former or ex-smokers was almost similar to that of the never smokers. Findings from multiple logistic regression analysis showed that current smokers were 37% less likely to be cognitively impaired, compared to the never smokers (odds ratio [OR] = .63; 95% confidence interval [CI]: .46-.86) while controlling for potential confounders. No difference in cognitive function was observed between former smokers and never smokers (OR = .94; 95% CI: .71-1.25).
  
  
  CONCLUSIONS
  Although the findings indicated a negative association between cigarette smoking and cognitive impairment, we are unable to conclude whether this relationship is causal or affected by other unmeasured confounding factors, especially survival bias.
authors.affiliation: Institute of Gerontology, Universiti Putra Malaysia, Serdang, Selangor, Malaysia Iranian Research Center on Aging, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran.
authors.forename: Yadollah Abolfathi
authors.initials: YA
authors.lastname: Momtaz
authors.affiliation: Institute of Gerontology, Universiti Putra Malaysia, Serdang, Selangor, Malaysia Department of Human Development and Family Studies, Faculty of Human Ecology, Institute of Gerontology, Universiti Putra Malaysia, Serdang, Selangor, Malaysia.
authors.forename: Rahimah
authors.initials: R
authors.lastname: Ibrahim
authors.affiliation: Institute of Gerontology, Universiti Putra Malaysia, Serdang, Selangor, Malaysia Department of Human Development and Family Studies, Faculty of Human Ecology, Institute of Gerontology, Universiti Putra Malaysia, Serdang, Selangor, Malaysia aizan@upm.edu.my.
authors.forename: Tengku Aizan
authors.initials: TA
authors.lastname: Hamid
authors.affiliation: Institute of Gerontology, Universiti Putra Malaysia, Serdang, Selangor, Malaysia.
authors.forename: Sen Tyng
authors.initials: ST
authors.lastname: Chai
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003072:Cognition Disorders / Q000453:epidemiology / Q000517:prevention & control*; D015897:Comorbidity; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008296:Malaysia / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D012907:Smoking / Q000453:epidemiology
keywords: Malaysia; aged; cigarette smoking; cognitive impairment