Lifestyle Behavior Associated with Risk for Dementia
Lifestyle Behavior Associated with Risk for Dementia
Objectives: To identify distinct behavioral patterns of diet, exercise, social interaction, church attendance, alcohol consumption, and smoking and to examine their association with subsequent dementia risk.
Design: Longitudinal, population-based dementia study.
Setting: Rural county in northern Utah, at-home evaluations.
Participants: Two thousand four hundred ninety-one participants without dementia (51% male, average age 73.0 ± 5,7; average education 13.7 ± 4.1 years) initially reported no problems in activities of daily living and no stroke or head injury within the past 5 years.
Measurements: Six dichotomized lifestyle behaviors were examined (diet: high ≥ median on the Dietary Approaches to Stop Hypertension scale; exercise: ≥5 h/wk of light activity and at least occasional moderate to vigorous activity; church attendance: attending church services at least weekly; social Interaction: spending time with family and friends at least twice weekly; alcohol: currently drinking alcoholic beverages ≥ 2 times/wk; nonsmoker: no current use or fewer than 100 cigarettes ever). Latent class analysis (LCA) was used to identify patterns among these behaviors. Proportional hazards regression modeled time to dementia onset as a function of behavioral class, age, sex, education, and apolipoprotein E status. Follow-up averaged 6.3 ± 5.3 years, during which 278 cases of incident dementia (200 Alzheimer's disease (AD)) were diagnosed.
Results: LCA identified four distinct lifestyle classes. Unhealthy–religious (UH-R; 11.5%), unhealthy–nonreligious (UH-NR; 10.5%), healthy–moderately religious (H-MR; 38.5%), and healthy–very religious (H-VR; 39.5%). UH-NR (hazard ratio (HR) = 0.54, P = .028), H-MR (HR = 0.56, P = .003), and H-VR (HR = 0.58, P = .005) had significantly lower dementia risk than UH-R. Results were comparable for AD, except that UH-NR was less definitive.
Conclusion: Functionally independent older adults appear to cluster into subpopulations with distinct patterns of lifestyle behaviors with different levels of risk for subsequent dementia and AD.
Frequent church attendance has been associated with slower cognitive decline, and inversely associated with cognitive dysfunction. High vegetable consumption and adherence to a "Mediterranean diet," with high vegetable, fruit, whole grain, and monounsaturated fatty acid intake have also been associated with less cognitive decline (over 4–11 years) and lower risk of dementia. Low to moderate alcohol consumption and abstention from smoking have similarly been associated with lower risk of dementia.
Collectively, these studies have shown that individual behaviors may influence the probability of dementia onset, but little work has been done to simultaneously examine a wide range of lifestyle behaviors for their collective influence. Because additive or interactive relationships between multiple lifestyle behaviors might affect underlying neurodegenerative processes, it is important to study their combined effects. The identification of lifestyle behavioral patterns can identify subpopulations that may have different risks of dementia, suggesting specific dementia prevention interventions.
Although risk of dementia, particularly AD, depends strongly on biological and genetic factors, lifespan developmental theory argues that there is flexibility (plasticity) in development, suggesting that individuals may influence late-life cognitive outcomes through lifestyle choices. This theory supports multivariate approaches to studying multivariate developmental phenomena. Behavior clusters may better capture the multivariate nature of behavior that influences late-life developmental outcomes such as dementia. Such behavioral clusters may contribute to development of "cognitive reserve" through exposure to cognitively stimulating educational, occupational, and leisure activities. It has been hypothesized that cognitive reserve allows more-efficient use of brain networks and compensates for disruption of standard processing networks when a normal network is damaged.
Six lifestyle behaviors were examined in a community sample of older adults residing in Cache County, Utah, where residents generally have a high prevalence of most attributes thought to contribute to healthy aging. Behavioral subgroups were sought, based on combinations of diet, exercise, smoking, alcohol consumption, social interaction, and church attendance. Associations between subgroup and subsequent dementia risk were examined, and it was hypothesized that participants with healthier behavioral patterns would have lower dementia rates.
Abstract and Introduction
Abstract
Objectives: To identify distinct behavioral patterns of diet, exercise, social interaction, church attendance, alcohol consumption, and smoking and to examine their association with subsequent dementia risk.
Design: Longitudinal, population-based dementia study.
Setting: Rural county in northern Utah, at-home evaluations.
Participants: Two thousand four hundred ninety-one participants without dementia (51% male, average age 73.0 ± 5,7; average education 13.7 ± 4.1 years) initially reported no problems in activities of daily living and no stroke or head injury within the past 5 years.
Measurements: Six dichotomized lifestyle behaviors were examined (diet: high ≥ median on the Dietary Approaches to Stop Hypertension scale; exercise: ≥5 h/wk of light activity and at least occasional moderate to vigorous activity; church attendance: attending church services at least weekly; social Interaction: spending time with family and friends at least twice weekly; alcohol: currently drinking alcoholic beverages ≥ 2 times/wk; nonsmoker: no current use or fewer than 100 cigarettes ever). Latent class analysis (LCA) was used to identify patterns among these behaviors. Proportional hazards regression modeled time to dementia onset as a function of behavioral class, age, sex, education, and apolipoprotein E status. Follow-up averaged 6.3 ± 5.3 years, during which 278 cases of incident dementia (200 Alzheimer's disease (AD)) were diagnosed.
Results: LCA identified four distinct lifestyle classes. Unhealthy–religious (UH-R; 11.5%), unhealthy–nonreligious (UH-NR; 10.5%), healthy–moderately religious (H-MR; 38.5%), and healthy–very religious (H-VR; 39.5%). UH-NR (hazard ratio (HR) = 0.54, P = .028), H-MR (HR = 0.56, P = .003), and H-VR (HR = 0.58, P = .005) had significantly lower dementia risk than UH-R. Results were comparable for AD, except that UH-NR was less definitive.
Conclusion: Functionally independent older adults appear to cluster into subpopulations with distinct patterns of lifestyle behaviors with different levels of risk for subsequent dementia and AD.
Introduction
Frequent church attendance has been associated with slower cognitive decline, and inversely associated with cognitive dysfunction. High vegetable consumption and adherence to a "Mediterranean diet," with high vegetable, fruit, whole grain, and monounsaturated fatty acid intake have also been associated with less cognitive decline (over 4–11 years) and lower risk of dementia. Low to moderate alcohol consumption and abstention from smoking have similarly been associated with lower risk of dementia.
Collectively, these studies have shown that individual behaviors may influence the probability of dementia onset, but little work has been done to simultaneously examine a wide range of lifestyle behaviors for their collective influence. Because additive or interactive relationships between multiple lifestyle behaviors might affect underlying neurodegenerative processes, it is important to study their combined effects. The identification of lifestyle behavioral patterns can identify subpopulations that may have different risks of dementia, suggesting specific dementia prevention interventions.
Although risk of dementia, particularly AD, depends strongly on biological and genetic factors, lifespan developmental theory argues that there is flexibility (plasticity) in development, suggesting that individuals may influence late-life cognitive outcomes through lifestyle choices. This theory supports multivariate approaches to studying multivariate developmental phenomena. Behavior clusters may better capture the multivariate nature of behavior that influences late-life developmental outcomes such as dementia. Such behavioral clusters may contribute to development of "cognitive reserve" through exposure to cognitively stimulating educational, occupational, and leisure activities. It has been hypothesized that cognitive reserve allows more-efficient use of brain networks and compensates for disruption of standard processing networks when a normal network is damaged.
Study Purpose
Six lifestyle behaviors were examined in a community sample of older adults residing in Cache County, Utah, where residents generally have a high prevalence of most attributes thought to contribute to healthy aging. Behavioral subgroups were sought, based on combinations of diet, exercise, smoking, alcohol consumption, social interaction, and church attendance. Associations between subgroup and subsequent dementia risk were examined, and it was hypothesized that participants with healthier behavioral patterns would have lower dementia rates.
