A 67-year-old man asks about what he can do to prevent dementia. He reports his mother had dementia, and he wants to do everything he can to prevent it. Which of the following has evidence of benefit?
B) Vitamin E
C) Multivitamin injection (MVI)
D) Keto diet
E) Red wine
FDA-approved therapies for dementia
To date the actual therapies for dementia have been disappointing. Donepezil, the most prescribed medication for the treatment of dementia has a number-needed-to treat (NNT) over 17, and causes frequent side effects. Aducanumab was recently approved by the Food and Drug Administration for the treatment of Alzheimer’s disease (AD), but controversy has arisen, as the clinical results were modest, and the price tag will be large – estimated at $30,000-$50,000/year.
Preventive options that may decrease the likelihood of dementia
Patients often ask the question stated above. Regarding how to respond to that question, choice C, MVI, has some recent evidence of benefit. Baker and colleagues studied the effect of cocoa extract and multivitamins on cognitive function in the COSMOS-Mind trial. A total of 2,262 people were enrolled, and over 90% completed baseline and at least one annual cognitive assessment. Cocoa extract had no impact on global cognition (confidence interval [CI], –.02-.08, P = .28), but MVI supplementation did have a statistically significant impact on global cognition (CI, .02-.12, P less than .007).
Vitamin E has been enthusiastically endorsed in the past as a treatment to prevent cognitive decline. The most recent Cochrane review on vitamin E concluded there was no evidence that the alpha-tocopherol form of vitamin E given to people with MCI prevents progression to dementia, or that it improves cognitive function in people with MCI or dementia due to AD.
Exercise has long been a mainstay of our advice to patients as something they can do to help prevent dementia. Yu and colleagues did a meta-analysis of almost 400 randomized controlled trials and observational studies to grade the evidence on different interventions. They gave exercise a grade B for evidence of benefit.
A recent study addressed this issue, and I think it is helpful on quantifying how much exercise is needed. Del Pozo Cruz and colleagues did a prospective population-based cohort study of 78,000 adults aged 40-79, with an average of 6.9 years of follow up. The optimal step count was 9,826 steps (hazard ratio [HR], 0.49; 95% CI, 0.39-0.62) and the minimal step count for benefit was 3,826 steps (HR, 0.75; 95% CI, 0.67-0.83).
The other major modifiable factors to consider are problems with special senses. Both vision loss and hearing loss have been associated with cognitive impairment.
Shang and colleagues published a meta-analysis of 14 cohort studies addressing vision impairment and cognitive function involving more than 6 million individuals. They concluded that vision impairment is associated with an increased risk of both dementia and cognitive impairment in older adults.
Loughrey and colleagues performed a meta-analysis of 36 studies addressing hearing loss and cognitive decline. They reported that, among cross-sectional studies, a significant association was found for cognitive impairment (odds ratio [OR], 2.00; 95% CI, 1.39-2.89) and dementia (OR, 2.42; 95% CI, 1.24-4.72). A similar finding was present in prospective cohort studies with a significant association being found for cognitive impairment (OR, 1.22; 95% CI, 1.09-1.36) and dementia (OR, 1.28; 95% CI, 1.02-1.59).
A 25-year prospective, population-based study of patients with hearing loss revealed a difference in the rate of change in MMSE score over the 25-year follow-up between participants with hearing loss not using hearing aids matched with controls who didn’t have hearing loss. Those with untreated hearing loss had more cognitive decline than that of patients without hearing loss. The subjects with hearing loss using a hearing aid had no difference in cognitive decline from controls.
Several simple and safe interventions may protect our patients from cognitive decline. These include taking a daily multivitamin, walking more than 4,000 steps a day, and optimizing vision and hearing.
Dr. Paauw is professor of medicine in the division of general internal medicine at the University of Washington, Seattle, and he serves as third-year medical student clerkship director at the University of Washington. Contact Dr. Paauw at firstname.lastname@example.org.
This article originally appeared on MDedge.com, part of the Medscape Professional Network.
Lead Image: Getty Images
Image 1: Douglas A. Paauw, MD
© 2022 Frontline Medical Communications Inc.
Any views expressed above are the author's own and do not necessarily reflect the views of MDedge or its affiliates.
Cite this: How Can I Keep From Losing My Mind? - Medscape - Nov 09, 2022.