The Physiological Factors of Diabetes and Their Effect on the Cognitive and Emotional Functioning in Older Populations: A Secondary Data Analysis
Background: The rates of Type 2 Diabetes (T2D) have increased over the past 20 years in all age groups. The physiological factors that underlie T2D could have impact on specific brain pathways that support cognitive and emotional functioning. Aims and Objective: The goal of this study was to examine whether older Mexican American individuals with a history of T2D were more likely to develop later cognitive impairment and/or depression. Hypotheses: It was predicted that elderly participants (mean age at time of interview = 87.87 years) with a history of T2D onset prior to age 65, are more likely to have dementia-related symptoms and/or symptoms of depression, as compared to elderly participants with no earlier history of T2D. Specifically, respondents with T2D were predicted to have greater likelihood of diagnosed dementia (yes/no); lower (worse) Total Mini-Mental Status Examination scores; and higher depression rating scale scores. Methods: The hypotheses were tested using respondent data from the Hispanic Established Populations for the Epidemiologic Study of the Elderly (HEPESE) Wave 8, 2012-2013 [Arizona, California, Colorado, New Mexico, and Texas] (ICPSR 36578). The original Wave 8 dataset included 744 respondents; N = 506 had data points needed for the proposed analyses. The mean age of Wave 8 respondents included for analysis was 87.87 years. The analyzed sample was 65.6% female; 29.8% had a T2D diagnosis; and 19.8% had a formal diagnosis of Alzheimer’s or Dementia. Descriptive statistics were calculated for all variables. Hypotheses involving categorical variables were tested using Chi-Square tests. For continuous variables, distribution analyses (N, standard deviation, variance, skewness) were examined and data were analyzed using two-way ANOVAs. Results: Chi-square tests were not significant. The frequency of dementia diagnoses among respondents with early or any T2D, were not significantly increased as compared to respondents without early T2D or any T2D. Overall, the ANOVA results were also not significant but revealed some interesting trends. Regarding mental function scores, the overall model predicting MMSE scores from T2D, sex, and the interaction, was statistically significant, but none of the individual factors were significant. When the direction of effects was examined, it was opposite to the original prediction. Respondents with T2D had higher rather than lower mental function scores, as compared to those without T2D. Regarding ratings for reported depression, the overall model was significant, and the tests of individual factors showed that this was attributable to higher levels of depression symptoms reported by females as compared to males. Conclusions: Despite using all the available respondents for these exploratory secondary data analyses, small sub-group sizes limited the statistical power to detect possible effects. Nonetheless, the findings suggested that a T2D diagnosis may yield protective effects for the brain, perhaps due to T2D medication effects, and/or healthier lifestyle and dietary recommendations usually given to those with a T2D diagnosis. As compared to elderly males, elderly females with earlier T2D reported significantly more depression than males. While largely not significant, the findings suggested several novel directions for future research. Studies are needed to determine whether increased mental function among T2D participants may be attributable to medication use or lifestyle changes. Recent studies have suggested that Metformin, a common treatment for T2D, is directly and indirectly anti-inflammatory. Further studies are needed to understand whether the increased MMSE scores among T2D participants in this study could be attributable to the medications prescribed, and or lifestyle and dietary changes typically recommended, including increased exercise and reduced sugar intake. Additional studies are also needed to determine whether female T2D participants are uniquely vulnerable to depressive symptoms. As life expectancy continues to increase, it may be important to develop standards that aid in appropriately diagnosing, treating, and managing symptoms of Type 2 Diabetes (T2D), in an effort to help lower the risk for developing Alzheimer’s Disease/Dementia in later life. Further research is needed to explore the connection between these disorders, specifically in Hispanic populations.
Aging|Psychobiology|Endocrinology|Hispanic American studies|Public health
Alvidrez, Celeste Anahi, "The Physiological Factors of Diabetes and Their Effect on the Cognitive and Emotional Functioning in Older Populations: A Secondary Data Analysis" (2021). ETD Collection for University of Texas, El Paso. AAI28869341.