Risk factors for incident dementia in the very old

• Background : Several risk factors for dementia, Alzheimer's disease, and cognitive impairment have been established; however, knowledge about risk factors in the very old population (>= 85 years) is limited. This study describes the association of several baseline factors with dementia in participants aged >= 85 years, and investigates factors associated with a higher risk of incident dementia over five years. Methods : The participants in this population-based cohort study were aged 85, 90, and >= 95 years at baseline (2000-2002). Data were collected during home visits for interviews and testing, from a review of medical records, and/or interviewing the caregiver or next of kin. After five years 212 participants could be followed up concerning incident dementia. Multivariate logistic regression was used. Results : At baseline, 100/353 (28%) of participants had a dementia diagnosis. Over five years, 71/212 (33.5%) participants developed dementia. Few participants with dementia at baseline remained alive after five years (12%). Depression at the baseline and follow-up time were associated with a higher risk of dementia, odds ratio (OR) (95% CI, p-value) 2.91 (1.37-6.16, 0.005) and 1.61 (1.26-2.05, <0.001) respectively. More social contact and a higher Mini-Mental State Examination score at baseline were associated with lower risk of incident dementia, OR (95% CI, p-value) 0.87 (0.78-0.97, 0.009) and 0.83 (0.74-0.93, 0.001) respectively. Conclusions : Prevalence and incidence of dementia are high in very old people and dementia appears to be a fatal disorder. Depression is associated with higher risk of incident dementia over five years whereas more frequent social contacts and a higher MMSE score are associated with lower risk.

Subject headings

Medical and Health Sciences  (ssif)

Clinical Medicine  (ssif)

Geriatrics  (ssif)

Medicin och hälsovetenskap  (ssif)

Klinisk medicin  (ssif)

Geriatrik  (ssif)

Genre

government publication  (marcgt)

Keyword

aged

80 and over

longitudinal

population-based

depression

social isolation

prevalence

incidence