Dietary Treatments for Cognitive Impairment in Older Adults

Feasibility and Efficacy of Dietary Interventions for Cognitive Impairment in Older Adults

This trial seeks to establish the feasibility of implementing a ketogenic, modified Atkins diet (MAD) to older adults with mild cognitive impairment (MCI) or early Alzheimer's disease (AD) living in the community. A secondary aim is to determine whether adherence to the MAD results in better cognitive test scores than adherence to a non-ketogenic control diet. A final aim is to determine the role of apolipoprotein E (ApoE) genotype in participants' response to the MAD. Participants will be randomly assigned to a 12-week trial of either the MAD or a placebo diet based on the National Institute on Aging's recommendations for senior nutrition.

Study Overview

• Status: Completed
• Conditions: Mild Cognitive Impairment; Probable Alzheimer's Disease
• Intervention / Treatment: Other: Modified Atkins Diet; Other: NIA Diet for Seniors

Detailed Description

It is well established that Alzheimer's disease (AD) is associated with insulin resistance and, hence, abnormal glucose metabolism. In fact, abnormalities in the brain's uptake of glucose can be observed on PET imaging in advance of clinical symptoms. In patients with established dementia due to AD, the severity of cognitive impairment is strongly correlated with the decrease in glucose uptake. Ketone bodies, the products of fat metabolism, can serve as a "backup" fuel when glucose is unavailable. Ketone body metabolism appears to bypass the metabolic processes that are abnormal in AD and may provide better nourishment for neurons. As a result, ketone body metabolism may slow cognitive decline or even improve cognition in patients with AD.

Participants will be 60 people, age 60 or older, with MCI or mild probable AD and without significant cardiovascular disease. They will be required to obtain the consent of their primary care physicians for their participation. Each patient will have a study partner who is cognitively healthy, lives with the participant, and can help him/her adhere to the diet. A research dietitian will teach participants and partners the new diet and monitor participants' adherence with food logs, in-person assessments, and urine ketone testing. After an initial baseline visit, participants will complete four in-person assessments during which adherence to the diet will be assessed and neurocognitive tests will be administered. It is hypothesized that the MAD will be feasible and well tolerated by seniors with MCI and AD. It is further hypothesized that adherence to the MAD will be associated with a greater increase (or less decline) in cognitive test scores than the placebo diet, particularly for those participants who do not carry an ApoE ε4 allele.

• Study Type: Interventional
• Enrollment (Actual): 38
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Maryland
    • Baltimore, Maryland, United States, 21205
      • Johns Hopkins Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 60 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• diagnosis of mild cognitive impairment or Alzheimer's disease
• availability of cohabitating study partner without cognitive impairment
• consent of primary care physician

Exclusion Criteria:

• history of stroke
• history of coronary artery disease
• history of pancreatitis
• untreated hypothyroidism or B12 deficiency
• history of renal disease or recurrent kidney stones
• history of liver disease
• insulin-dependent diabetes
• body mass index <18.5
• multiple food allergies
• follow strict diet (e.g., vegetarian, gluten-free)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Modified Atkins Diet; modified Atkins diet; fewer than 20 mg. carbohydrates per day, supplemented by extra dietary fats	Other: Modified Atkins Diet; Other Names: ketogenic diet
Active Comparator: NIA Diet for Seniors; Diet recommended by NIA for seniors	Other: NIA Diet for Seniors

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Feasibility for MAD Group	Achieving moderate ketosis (>=40 mg.dl) at 3 consecutive follow-up visits	12 weeks
Feasibility for Control Group	Achieving a Healthy Eating Index (>=85) at 3 consecutive follow-up visits	12 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Efficacy for Cognition	Composite Memory Score (mean z-score on delayed recall of HVLT-R and BVMT-R)	12 weeks
Efficacy for Function	Change in MDS-HC Instrumental Activities of Daily Living Score	12 weeks

Collaborators and Investigators

• Sponsor: Johns Hopkins University
• Investigators: Principal Investigator: Jason Brandt, Ph.D., Johns Hopkins University

Study record dates

Study Major Dates

• Study Start (Actual): August 1, 2015
• Primary Completion (Actual): July 1, 2019
• Study Completion (Actual): July 1, 2019

Study Registration Dates

• First Submitted: August 10, 2015
• First Submitted That Met QC Criteria: August 10, 2015
• First Posted (Estimate): August 13, 2015

Study Record Updates

• Last Update Posted (Actual): September 6, 2019
• Last Update Submitted That Met QC Criteria: September 4, 2019
• Last Verified: September 1, 2019

More Information

Terms related to this study

• Keywords: dementia; cognition; nutrition; elderly; diet; neuropsychological
• Additional Relevant MeSH Terms: Mental Disorders; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Neurocognitive Disorders; Neurodegenerative Diseases; Dementia; Tauopathies; Cognition Disorders; Alzheimer Disease; Cognitive Dysfunction
• Other Study ID Numbers: IRB00066092