Living in an area in which neighbors connect and are willing to intervene for the common good, also known as neighborhood cohesion, mitigates the negative effects tooth loss has on cognitive decline. The study was published in the Archives of Gerontology and Geriatrics.
However, neighborhood disorder was not associated with cognitive decline, the authors wrote.
"The findings highlight the complex interplay between oral health and neighborhood environments in shaping cognitive function over time," wrote the authors, led by Ruotong Liu, PhD, of New York University in New York City (Arch Gerontol Geriatr, March 5, 2025, Vol. 133, 105806).
The worldwide burden of edentulism is expected to rise due to population growth and aging, with a substantial effect anticipated by 2040, according to a study in the International Dental Journal. By 2040, the global prevalence of tooth loss is projected to increase by about 12%, reaching 5,004 per 100,000, the authors wrote.
Previous research has shown that there is a relationship between edentulism and cognitive decline in older adults. However, only limited research has measured the synergistic effects of poor oral health and neighborhood environment on cognitive health.
To explore whether a neighborhood environment moderates the correlation between tooth loss and cognitive function over time, data from the U.S. Health and Retirement Study were used to analyze 9,994 adults ages 60 and older with 39,976 person-wave observations between 2006 and 2020.
The modified telephone interview for cognitive status was used to assess cognitive function. Complete tooth loss was self-reported, and neighborhood environment included perceived neighborhood cohesion and disorder, according to the study.
Over time, patients with tooth loss showed an accelerated decline in cognitive function compared to those with teeth (β = -0.57, 95 % confidence interval [CI]: -0.98 to -0.16), the authors wrote.
Furthermore, neighborhood cohesion moderated the relationship between tooth loss and cognitive function over time (β = 0.08, 95 % CI: 0.01 to 0.15). The negative effect of tooth loss on cognitive decline was attenuated in patients reporting higher neighborhood cohesion. However, neighborhood disorder had no significant correlations with cognitive function, they wrote.
Moreover, the study had limitations, including that this research relied on self-reported measures of tooth loss, which may introduce reporting bias, the authors wrote.
Nevertheless, this study may have vital implications for intervention development and health policy. In areas with a high prevalence of dental problems, it may be beneficial to create community-based interventions that promote neighborhood cohesion, such as creating inclusive social spaces and developing support networks, they wrote.
"By identifying modifiable neighborhood factors that could help maintain cognitive function among older adults with oral health challenges, this study contributes to the growing evidence base for multilevel approaches to promote healthy cognitive aging," Liu and colleagues wrote.
