A study published in the journal Alzheimer’s Research & Therapy finds that intensive lifestyle changes can significantly improve cognition and function in patients with mild cognitive impairment or early dementia due to Alzheimer’s disease. 

Study: Effects of intensive lifestyle changes on the progression of mild cognitive impairment or early dementia due to Alzheimer’s disease: a randomized, controlled clinical trial. Image Credit: Prostock-studio / Shutterstock

Background

Several lifestyle factors, including unhealthy diet, lack of physical activity, smoking, obesity, diabetes, social isolation, and emotional stress, are known to trigger the onset and progression of dementia, including Alzheimer’s disease.

A total of 12 potentially modifiable risk factors have been identified by a Lancet commission on dementia prevention, intervention, and care, which are collectively responsible for about 40% of the global burden of dementia.

Existing evidence indicates that consumption of high amounts of vegetables and omega-3 fatty acids can reduce the risk of Alzheimer’s disease by 38% and 60%, respectively. In contrast, consumption of saturated fats or trans-fats has been found to increase the Alzheimer’s disease risk by more than 2-folds.

Studies investigating lifestyle risk factors have found that multidomain lifestyle interventions are more effective than single-domain interventions in reducing the risk of dementia and Alzheimer’s disease. A multimodal intervention of diet, exercise, cognitive training, and vascular risk monitoring has been found to maintain cognitive functions in older adults who are at higher risk of developing dementia.   

In this multicenter randomized controlled clinical trial, scientists have investigated the effect of a 20-week intensive multidomain lifestyle intervention on the progression of mild cognitive impairment or early dementia in patients with Alzheimer’s disease.

Study design

The trial was conducted on a total of 51 adults aged 45 – 90 years who were diagnosed with mild cognitive impairment of early-stage dementia due to Alzheimer’s disease. Of all participants, 26 were randomly assigned to the intervention group, and 25 were assigned to the usual habits and care control group.

The intervention group participants followed an intensive multidomain lifestyle program for 20 weeks. The lifestyle intervention included a diet (minimally processed plant-based diet low in harmful fats and low in refined carbohydrates and sweeteners with selected supplements), moderate exercise, stress management approaches, and support groups. The control group participants were asked not to make any lifestyle changes for 20 weeks.

At the 20-week follow-up visit, all participants underwent clinical and cognitive assessments. Four tests were carried out to assess the changes in participants’ cognition and function, including the Clinical Global Impression of Change (CGIC), the Alzheimer’s Disease Assessment Scale (ADAS-Cog), the Clinical Dementia Rating–Sum of Boxes (CDR-SB), and the Clinical Dementia Rating Global (CDR-G).

Blood-based biomarkers, including plasma aβ42/40 ratio and microbiome taxa, were also analyzed as secondary outcome measures. Plasma aβ42/40 ratio is used to assess the risk of having Alzheimer’s disease pathology in patients with mild cognitive impairment or dementia.

Important observations

The analysis of primary outcomes at 20 weeks revealed significant improvement in cognition and function in the multidomain lifestyle intervention group and worsening in the control group.

The lifestyle intervention group experienced significantly less progression of clinical dementia than the control group.

The analysis of blood-based biomarkers revealed a 6.4% increase in plasma aβ42/40 ratio in the intervention group and an 8.3% decrease in the control group. A high plasma aβ42/40 ratio is known to be associated with low deposition of beta-amyloid (a major hallmark of Alzheimer’s disease) in the brain.

Other biomarkers, including glycated hemoglobin, insulin, glycoprotein acetyls, low-density lipoprotein-cholesterol, and β-Hydroxybutyrate (ketone bodies), also showed improvement in the intervention group compared to the control group.

Overall, the study found that the degree of lifestyle change (between baseline and 20-week follow-up) and adherence to desired lifestyle changes were significantly associated with the changes in cognition and function.

In other words, a higher adherence to the prescribed lifestyle intervention was found to be associated with a more significant improvement in cognition and function.

The microbiota analysis showed significant improvement in the intervention group but not the control group. Specifically, the intervention group exhibited an induction in microbial species known to associate with a reduced risk of Alzheimer’s disease and a reduction in microbial species known to increase the disease risk.

Study significance

The study finds a beneficial impact of intensive lifestyle changes for 20 weeks on cognition and function in patients with mild cognitive impairment or early dementia due to Alzheimer’s disease.

These lifestyle changes can be availed at a much lower cost than the disease treatment and thus might be considered valuable interventions to prevent Alzheimer’s disease.

As the scientists suggested, future clinical trials should consider a larger sample size and longer follow-up duration to determine the long-term outcomes of intensive lifestyle changes in more diverse Alzheimer’s disease populations.