Scientists conducted a pilot randomized controlled clinical trial to investigate whether a healthy multicultural diet can reduce cognitive decline and the risk of Alzheimer’s disease in adults aged 40 to 65.
Study: Multicultural healthy diet to reduce cognitive decline and risk of Alzheimer’s disease: study protocol for a pilot randomized controlled trial. Image credit: Olga Klochanko/Shutterstock
They have published new study protocols for ambulatory cognitive assessment and web-based dietary intake assessment in Contemporary Clinical Trials.
background
Alzheimer’s disease and related dementias (ADRD) are very common in the United States. The number of American adults living with ADRD is expected to increase from 6.2 million to 12.7 million by 2050.
Diet is a potentially modifiable risk factor for ADRD and related cognitive impairment. An anti-inflammatory diet, which includes large amounts of vegetables, fruits, whole grains and fish, is known to reduce cognitive decline and improve mood.
The current study aims to investigate the effects of a healthy multicultural diet to reduce the risk of Alzheimer’s disease and cognitive decline in a diverse population of adults living in the Bronx, New York.
Study design
The current randomized controlled trial is the first of its kind to combine new methods of ambulatory cognitive assessment with a web-based dietary intake record assessment. This ambulatory strategy assessed cognition and diet in real time for seven days every nine months. This led to a collection of 140 assessments of cognition and 28 days of real-time diet records per person.
Study participants were randomly assigned to two groups. Participants in the multicultural healthy diet group were exposed to the dietary intervention for 18 months. The sustainability of the intervention was assessed for an additional nine months.
Participants in the control group were exposed to a standard healthy diet intervention during the same period. Conventional methods were used in both the clinic and outpatient setting to evaluate the study results. Ambulatory methods were applied to reflect the natural settings in which people perform cognitive tasks in their daily lives.
The Mobile Monitoring of Cognitive Change (M2C2) smartphone application was used for ambulatory assessment of various cognitive tasks, including processing speed, visuospatial working memory, associative memory binding to short term, long term associative memory and working memory capacity.
Daily dietary intake was recorded using the National Cancer Institute’s 24-hour self-administered food records (ASA24).
Survey design
A total of six surveys, including one “wake-up survey,” four “notified surveys,” and one “bedtime survey,” were administered each day via the smartphone app.
The awakening survey was designed to collect information about the previous night’s sleep pattern, expectations for the day, self-ratings of cognition, momentary food recording, and physical activity prior to the awakening survey .
The reported survey was designed to collect information on self-rated emotional behaviors and cognition, ratings of time pressure and distraction since the last survey, momentary food records, and physical activity records. The bedtime survey also followed the same design as a notified survey.
Ambulatory cognitive assessments were performed at the end of each waking and reported survey. Dietary records were collected during each outpatient assessment.
Results of the study
The study assessed a composite global cognition score derived from the M2C2 ambulatory cognitive assessments at nine months after study initiation. In addition, the study assessed the adaptability of a multicultural healthy diet in a diverse population of adults in the Bronx, New York.
At nine months, several serum biomarkers were measured, including total folate and vitamers, tocopherols, carotenoids, vitamin B12, and fatty acids to determine the impact of the dietary intervention. Self-reported consumption of foods, such as fruits and vegetables, was assessed.
Short- and long-term associations between the dietary intervention and cognitive performance were assessed.
Study the importance
The ambulatory assessments of cognitive and dietary intake performed in the study provide a rich real-time database for characterizing the impact of dietary interventions on cognitive performance in adults.
The study includes ambulatory and in-clinic cognitive assessments for comparison and validation. The ability of ambulatory assessments to collect data remotely is particularly effective in a constrained situation such as the coronavirus disease 2019 (COVID-19) pandemic. Although in-clinic assessments have been interrupted during the pandemic, cutting-edge outpatient methods have allowed the study to continue with minimal disruption.