Statin use and the risk of incident dementia: the Cardiovascular Health Study.
BACKGROUND
Statins (3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors) reduce cardiovascular risk through mechanisms that might affect the development of dementia.


OBJECTIVE
To evaluate whether statin use is associated with a lower risk of dementia compared with never use of lipid-lowering agents (LLAs).


METHODS
Cohort study of community-dwelling adults 65 years and older. The analysis included 2798 participants free of dementia at baseline.


METHODS
Using Cox proportional hazards regression analysis, we estimated the risk of incident all-cause and type-specific dementia associated with time-dependent statin therapy compared with never use of LLAs. The primary analyses incorporated a 1-year lag between exposure and outcome. Secondary analyses included the final year of exposure and modeled statin use as current use vs nonuse to simulate a case-control approach.


RESULTS
Compared with never use of LLAs, ever use of statins was not associated with the risk of all-cause dementia (multivariable-adjusted hazard ratio [HR], 1.08; 95% confidence interval [CI], 0.77-1.52), Alzheimer disease alone (HR, 1.21; 95% CI, 0.76-1.91), mixed Alzheimer disease and vascular dementia (HR, 0.87; 95% CI, 0.44-1.72), or vascular dementia alone (HR, 1.36; 95% CI, 0.61-3.06). In contrast, in secondary analyses, current use of statins compared with nonuse of LLAs was associated with HRs of 0.69 (95% CI, 0.46-1.02) for all-cause dementia and 0.56 (95% CI, 0.35-0.92) for any Alzheimer disease.


CONCLUSIONS
In this cohort study, statin therapy was not associated with a decreased risk of dementia. Methodological differences may explain why results of this cohort investigation differ from those of prior case-control studies. Additional investigation is needed to determine whether and for whom statin use may affect dementia risk.
Rea
Thomas D
TD
Department of Medicine, University of Washington, Seattle 98101, USA. rea123@u.washington.edu
Breitner
John C
JC
Psaty
Bruce M
BM
Fitzpatrick
Annette L
AL
Lopez
Oscar L
OL
Newman
Anne B
AB
Hazzard
William R
WR
Zandi
Peter P
PP
Burke
Gregory L
GL
Lyketsos
Constantine G
CG
Bernick
Charles
C
Kuller
Lewis H
LH
D000368:Aged; D000369:Aged, 80 and over; D002318:Cardiovascular Diseases / Q000517:prevention & control*; D015331:Cohort Studies; D003704:Dementia / Q000517:prevention & control*; D005260:Female; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000627:therapeutic use*; D006949:Hyperlipidemias / Q000150:complications / Q000188:drug therapy*; D008297:Male
D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors