ST. LOUIS — Sixteen percent of the world's population struggles with constipation, and a new study shows it could also affect brain health.
The finding was released at the Alzheimer's Association International Conference 2023 underway in Amsterdam, Netherlands.
Sarah Lovegreen, V.P. of programs at the Alzheimer's Association Greater Missouri Chapter put the report into perspective this way.
"It’s important to note it wasn't a causal study,” Lovegreen said. “We're really just looking at some risk factors and a correlation between them, and folks with chronic constipation had a significant decline in their cognitive health to the point where they aged three years faster cognitively than those who didn't have chronic constipation.”
Chronic constipation is defined by having a bowel movement once every three or more days. It’s been associated with long-term health issues like inflammation, hormonal imbalances, anxiety and depression.
Older adults are more at risk due to age-related factors like fiber-deficient diets, lack of exercise and the use of certain constipating drugs to treat other medical conditions.
To study the relationship between constipation and brain health, Chaoran Ma, M.D., Ph.D., former research fellow at Brigham and Women’s Hospital and Harvard Medical School and current Assistant Professor at University of Massachusetts Amherst, analyzed three prospective studies of more than 110,000 middle-aged people in the Nurses’ Health Study, the Nurses’ Health Study II, and the Health Professionals Follow-up Study. Ma and team collected data on all participants’ bowel movement frequency in 2012-2013 and their self-assessments of cognitive function from 2014 to 2017; objective cognitive function was measured between 2014 and 2018 in a subgroup of 12,696 participants.
They found that less frequent bowel movements were associated with poorer cognitive function. Compared to those with bowel movements once daily, constipated participants (bowel movements every three days or more) had significantly worse cognition, equivalent to 3.0 years more of chronological cognitive aging.
Bowel movement frequency of every three days or less was associated with 73% higher odds of subjective cognitive decline.
Lovegreen says local scientists are also studying the gut-brain health connection.
"We have Dr. Beau Ances here at Washington University who's looking at gut health specifically with stool samples, and some of his early work has found, you can actually see some gut microbiome changes” before and Alzheimer’s diagnosis.
The Alzheimer’s Association says the findings stress the importance of doctors talking with patients about constipation, especially older patients.
In a news release, the Alzheimer’s Association quoted Dong Wang, M.D., Sc.D., an assistant professor at Harvard Medical School, Brigham and Women’s Hospital and Harvard T.H. Chan School of Public Health, who said “interventions for preventing constipation and improving gut health include adopting healthy diets enriched with high-fiber and high-polyphenol foods such as fruits, vegetables and whole grains; taking fiber supplementation; drinking plenty of water every day; and having regular physical activity.”
Lovegreen urges anyone who's concerned to talk with their doctor.