Decreased prevalence of Alzheimer disease associated with 3-hydroxy-3-methyglutaryl coenzyme A reductase inhibitors.

CONTEXT

Increasing evidence suggests that cholesterol plays a role in the pathophysiology of Alzheimer disease (AD). For instance, an elevated serum cholesterol level has been shown to be a risk factor for AD.

OBJECTIVE

To determine whether patients taking 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins), which are a group of medicines that inhibit the synthesis of cholesterol, have a lower prevalence of probable AD.

DESIGN

The experiment uses a cross-sectional analysis comparing the prevalence of probable AD in 3 groups of patients from hospital records: the entire population, patients receiving 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (hereafter referred to as the statins), and patients receiving medications used to treat hypertension or cardiovascular disease.

PATIENTS

The subjects studied were those included in the computer databases of 3 different hospitals for the years October 1, 1996, through August 31, 1998.

MAIN OUTCOME MEASURES

Diagnosis of probable AD.

RESULTS

We find that the prevalence of probable AD in the cohort taking statins during the study interval is 60% to 73% (P < .001) lower than the total patient population or compared with patients taking other medications typically used in the treatment of hypertension or cardiovascular disease.

CONCLUSIONS

There is a lower prevalence of diagnosed probable AD in patients taking 2 different 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors-lovastatin and pravastatin. While one cannot infer causative mechanisms based on these data, this study reveals an interesting association in the data, which warrants further study. Arch Neurol. 2000;57:1439-1443