BACKGROUND: Several lines of evidence have linked cholesterol to dementia.

OBJECTIVE: To investigate lipid-lowering drug use and dementia development in a Finnish population.

METHODS: FINRISK is a large population-based survey of cardiovascular risk factors carried out since 1972 every 5 years using independent, random and representative population samples from different parts of Finland. Several cohorts were part of the WHO-MONICA study. Data from cohorts 1972-2002 were linked to the Hospital Discharge Registry and Drug Reimbursement Registry (1995-2007) to ascertain dementia diagnoses and lipid-lowering treatment. Selection criteria for the study were: (1) alive and without dementia in 1995; (2) age > or = 60 years (in 1995 for earlier cohorts and in 1997 or 2002 for later cohorts; (3) treatment prescribed at least 1 year before dementia diagnosis.

RESULTS: 17,597 persons were included in the study. Lipid-lowering treatment was related to decreased dementia risk. In Cox proportional hazards model, hazard ratio (95% CI) was 0.42 (0.37-0.49; controlled for age, sex, education, survey region, survey year, baseline cholesterol, body mass index and systolic blood pressure).

CONCLUSION: Preliminary results from the FINRISK study indicate that lipid-lowering drugs may have a beneficial effect in dementia prevention. Further data linkage is ongoing in order to investigate the roles of different types of lipid-lowering drugs.