title: Cohort Effects in the Prevalence and Survival of People with Dementia in a Rural Area in Northern Sweden.
abstract: BACKGROUND
  Recent studies suggest that trends in cardiovascular risk may result in a decrease in age-specific prevalence of dementia. Studies in rural areas are rare.
  
  
  OBJECTIVE
  To study cohort effects in dementia prevalence and survival of people with dementia in a Swedish rural area.
  
  
  METHODS
  Participants were from the 1995-1998 Nordanstig Project (NP) (n = 303) and the 2001-2003 Swedish National study on Aging and Care in Nordanstig (SNAC-N) (n = 384). Overall 6-year dementia prevalence and mortality in NP and SNAC-N were compared for people 78 years and older. Logistic regression analyses were used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for dementia occurrence using the NP study population as the reference group. Cox regression models were used to analyze time to death.
  
  
  RESULTS
  The crude prevalence of dementia was 21.8% in NP and 17.4% in SNAC-N. When the NP cohort was used as the reference group, the age- and gender-adjusted OR of dementia was 0.71 (95% CI 0.48-1.04) in SNAC-N; the OR was 0.47 (0.24-0.90) for men and 0.88 (0.54-1.44) for women. In the extended model, the OR of dementia was significantly lower in SNAC-N than in the NP cohort as a whole (0.63; 0.39-0.99) and in men (0.34; 0.15-0.79), but not in women (0.81; 0.46-1.44). The Cox regression models indicated that the hazard ratio of dying was lower in the SNAC-N than NP population.
  
  
  CONCLUSIONS
  Trends toward a lower prevalence of dementia in high-income countries seem to be evident in this Swedish rural area, at least in men.
authors.affiliation: Aging Research Center (ARC), Karolinska Institutet and Stockholm University, Stockholm, Sweden.|Center for Alzheimer Research at Karolinska Institutet, Stockholm, Sweden.|Centre for Research & Development, Uppsala University/County Council of Gävleborg, Sjukhuset i Gävle, Sweden.
authors.forename: Anders
authors.initials: A
authors.lastname: Wimo
authors.affiliation: Aging Research Center (ARC), Karolinska Institutet and Stockholm University, Stockholm, Sweden.|University of Gävle, Gävle, Sweden.
authors.forename: Britt-Marie
authors.initials: BM
authors.lastname: Sjölund
authors.affiliation: Aging Research Center (ARC), Karolinska Institutet and Stockholm University, Stockholm, Sweden.
authors.forename: Anders
authors.initials: A
authors.lastname: Sköldunger
authors.affiliation: Aging Research Center (ARC), Karolinska Institutet and Stockholm University, Stockholm, Sweden.
authors.forename: Chengxuan
authors.initials: C
authors.lastname: Qiu
authors.affiliation: Department of Geriatrics, Karolinska University Hospital, Stockholm, Sweden.|Division of Clinical Geriatrics, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm Sweden.
authors.forename: Inga
authors.initials: I
authors.lastname: Klarin
authors.affiliation: The Swedish Dementia Centre, Stockholm, Sweden.
authors.forename: Gunilla
authors.initials: G
authors.lastname: Nordberg
authors.affiliation: Aging Research Center (ARC), Karolinska Institutet and Stockholm University, Stockholm, Sweden.|The Swedish Red Cross University College, Stockholm, Sweden.
authors.forename: Eva
authors.initials: E
authors.lastname: von Strauss
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging; D015988:Cohort Effect; D003704:Dementia / Q000453:epidemiology* / Q000401:mortality; D005260:Female; D006801:Humans; D008297:Male; D015995:Prevalence; D012307:Risk Factors; D012424:Rural Population; D012737:Sex Factors; D015996:Survival Rate; D013548:Sweden / Q000453:epidemiology
keywords: Dementia; mortality; prevalence; rural population