Leveraging a genetically-informative study design to explore depression as a risk factor for type 2 diabetes: Rationale and participant characteristics of the Mood and Immune Regulation in Twins Study.

Background: Comorbidity between depression and type 2 diabetes is thought to arise from the joint effects of psychological, behavioral, and biological processes. Studies of monozygotic twins may provide a unique opportunity for clarifying how these processes inter-relate. This paper describes the rationale, characteristics, and initial findings of a longitudinal co-twin study aimed at examining the biopsychosocial mechanisms linking depression and risk of diabetes in mid-life. Methods: Participants in the Mood and Immune Regulation in Twins (MIRT) Study were recruited from the Mid-Atlantic Twin Registry. MIRT consisted of 94 individuals who do not have diabetes at baseline, representing 43 twin pairs (41 monozygotic and 2 dizygotic), one set of monozygotic triplets, and 5 individuals whose co-twin did not participate. A broad set of variables were assessed including psychological factors (e.g., lifetime history major depression (MD)); social factors (e.g., stress perceptions and experiences); and biological factors, including indicators of metabolic risk (e.g., BMI, blood pressure (BP), HbA1c) and immune functioning (e.g., pro- and anti-inflammatory cytokines), as well as collection of RNA. Participants were re-assessed 6-month later. Intra-class correlation coefficients (ICC) and descriptive comparisons were used to explore variation in these psychological, social, and biological factors across time and within pairs. Results: Mean age was 53 years, 68% were female, and 77% identified as white. One-third had a history of MD, and 18 sibling sets were discordant for MD. MD was associated with higher systolic (139.1 vs 132.2 mmHg, p=0.05) and diastolic BP (87.2 vs. 80.8 mmHg, p=0.002) and IL-6 (1.47 vs. 0.93 pg/mL, p=0.001). MD was not associated with BMI, HbA1c, or other immune markers. While the biological characteristics of the co-twins were significantly correlated, all within-person ICCs were higher than the within-pair correlations (e.g., HbA1c within-person ICC=0.88 vs. within-pair ICC=0.49; IL-6 within-person ICC=0.64 vs. within-pair=0.54). Among the pairs discordant for MD, depression was not substantially associated with metabolic or immune markers, but was positively associated with stress. Conclusions: Twin studies have the potential to clarify the biopsychosocial processes linking depression and diabetes, and recently completed processing of RNA samples from MIRT permits future exploration of gene expression as a potential mechanism.

Hispanic/Latino Ethnic Identity and Diabetes: An Examination of Underlying Acculturation Processes and the Hispanic/Latino Health Advantage.

Background. Hispanics/Latinos in the United States experience both a health advantage and disadvantage in developing diabetes. Ethnic identity, a predictor of psychological well-being, has not been widely applied to physical health outcomes. The objective of this study is to apply what is known regarding ethnic identity and psychological health to physical health outcomes (diabetes) and to explore the moderating effect of education as a possible underlying mechanism of the Hispanic Health Advantage/Disadvantage. Specifically, this study examines (a) the association between ethnic identity and diabetes prevalence among adult Hispanics/Latinos and (b) determines whether education modifies this relationship. Method. Data come from the nationally representative adult U.S. household study, National Latino and Asian American Study (NLAAS), collected in 2001 to 2003 (N = 1,746). Multiple logistic regression was conducted to examine the relationship between ethnic identity, education, and their interaction with likelihood of diabetes. Results. Hispanics/Latinos with high ethnic identity have a higher odds of reporting diabetes among those with 13 to 15 years of education (odds ratio: 1.84; 95% confidence interval: 1.16-2.92) and a lower odds among those with 16+ years of education (odds ratio: 0.53; 95% confidence interval: 0.34-0.84). Ethnic identity is associated with diabetes prevalence and the relationship is moderated by educational attainment. Conclusion. Given the growth, diversity, and diabetes disparities among Hispanics/Latinos, our buffering and exacerbating findings exemplify the complexity and fluidity of theory in understanding psychological/behavioral processes. The findings highlight the importance of designing targeted health interventions that take into account the diverse psychosocial and educational experiences of Hispanics/Latinos.

Engaging Underserved Community Members in Diabetes Self-Management: Evidence From the YMCA of Greater Richmond Diabetes Control Program.

PURPOSE: The purpose of this study was to identify factors influencing participant engagement in a community-based diabetes self-management program (DSMP), with a focus on the needs of underserved groups (eg, racial/ethnic minorities, low income). METHODS: Focus groups were conducted with participants (n = 22) from the YMCA of Greater Richmond's Diabetes Control Program, who were recruited using a purposeful sampling frame to capture a range of experiences. In-depth interviews were conducted with lay health coaches (n = 3). The RADaR qualitative analysis technique was used to identify themes related to factors across the continuum of engagement. RESULTS: Fear affected program enrollment and retention in complex ways. Peers and coaches were important for social support and accountability. The length of the program (12 weeks), accessible information, practical skill building, and emphasis on making small, feasible improvements in pursuit of larger goals were identified as critical for engagement and improving diabetes self-management. Health and outside obligations were the major barriers to program attendance. CONCLUSIONS: Participant and coach perspectives provide important insight into existing strengths of community-based DSMPs that can be expanded on to promote engagement as well as potential opportunities for improvement. Actionable recommendations for increasing engagement of underserved groups in community-based DSMPs are provided.

Successfully Managing Diabetes in a Community Setting: Evidence From the YMCA of Greater Richmond Diabetes Control Program.

Purpose The purpose of this study was to describe how a community-academic partnership developed and implemented a shared goal of evaluating the impact of a large community-based diabetes self-management program on diabetes care and mental health outcomes. Methods Data came from the YMCA of Greater Richmond Diabetes Control Program (DCP), a 12-week, group-format self-management program led by lay health coaches. Adults with type 2 diabetes (N = 312) completed baseline assessments of sociodemographic characteristics, diabetes history, and mental health. Four outcomes were assessed pre- and post-DCP on 141 participants who completed the program: hemoglobin A1C (A1C), weight, depressive symptoms (Patient Health Questionnaire-8), and glucose monitoring. The team worked with a Community Advisory Board throughout the research process. Results The DCP had wide geographic reach, including lower-income neighborhoods. The average age of the participants was 53.9 years, 71.4% were female, and 69% were African American. During the DCP, A1C declined from 8.4% to 7.6% (P < .001), but weight was unchanged (229.2 vs 227.9, P < .282). During the DCP, the proportion of participants with clinically significant depressive symptoms declined from 32.4% to 15.5% (P < .001), and frequency of glucose monitoring significantly increased. Conclusions The YMCA of Greater Richmond DCP has wide reach into underserved populations throughout the metropolitan area. This program is effective at improving diabetes self-management and mental health. Findings have implications for supporting academic-community partnerships to address diabetes disparities.

Stress, self-regulation, and context: Evidence from the Health and Retirement Survey.

Health-related behaviors, such as smoking, alcohol use, exercise, and diet, are major determinants of physical health and health disparities. However, a growing body of experimental research in humans and animals also suggests these behaviors can impact the ways our bodies respond to stress, such that they modulate (that is, serve as a means to self-regulate or cope with) the deleterious impact of stressful experiences on mental health. A handful of epidemiologic studies have investigated the intersection between stress and health behaviors on health disparities (both mental and physical), with mixed results. In this study we use a novel instrument designed to explicitly measure the self-regulatory motivations and perceived effectiveness of eight health-related self-regulatory behaviors (smoking, alcohol, drug use, overeating, prayer, exercise, social support, talking with a councilor) in a subset of the Health and Retirement Study (N=1,354, Mean age=67, 54% female). We find that these behaviors are commonly endorsed as self-regulatory stress-coping strategies, with prayer, social support, exercise, and overeating used most frequently. The likelihood of using particular behaviors as self-regulatory strategies varied significantly by sex, but not by race/ethnicity, education, or wealth. We also find that greater stress exposure is associated with higher likelihood of using these behaviors to self-regulate feelings of emotional distress, particularly health-harming behaviors like smoking, alcohol, and overeating. These findings provide an important link between sociological and psychological theoretical models on stress and empirical epidemiological research on social determinants of health and health disparities.

Commentary: Reconsidering the Role of Context in Diabetes Prevention.

A substantial gap remains between what we know about type 2 diabetes prevention and our ability to apply that knowledge in socially disadvantaged populations at highest risk. This gap results, in part, from a lack of integration between epidemiologic science and social psychology theory, particularly regarding the intersections of stress, self-regulatory health behaviors, and the biological mechanisms underlying the development of diabetes. In this commentary, we describe the utility of a theoretical framework that focuses on the intersection of biological, psychosocial, and environmental contexts as they apply to diabetes disparities, and how such a framework could inform a translational research agenda to reorient prevention efforts to address these inequalities. Such reorientation is needed to ensure that the implementation of prevention efforts does not inadvertently widen diabetes disparities.

Mobile health is worth it! Economic benefit and impact on health of a population-based mobile screening program in new Mexico.

BACKGROUND: HABITS for Life was a 3-year initiative to broadly deliver a statewide biometric and retinal screening program via a mobile unit throughout New Mexico at no charge to participants. The program goal-to identify health risk and improve population health status-was tested over a 3-year period. Value to participants and impact to the healthcare system were measured to quantify impact and value of investing in prevention at the community level. MATERIALS AND METHODS: We used the Mobile Health Map Return-on-Investment Calculator, a mobile screening unit, biometric screening, retinography, and community coordination. Our systems included satellite, DSL, and 3G connectivity, a Tanita® (Arlington Heights, IL) automated body mass index-measuring scale, the Cholestec® (Alere™, Waltham, MA) system for biomarkers and glycosylated hemoglobin, a Canon (Melville, NY) CR-1 Mark II camera, and the Picture Archiving Communication System. RESULTS: In this report for the fiscal year 2011 time frame, 6,426 individuals received biometric screening, and 5,219 received retinal screening. A 15:1 return on investment was calculated; this excluded retinal screening for the under-65 year olds, estimated at $10 million in quality-adjusted life years saved. Statistically significant improvement in health status evidenced by sequential screening included a decrease in total cholesterol level (p=0.002) (n=308) and an increase in high-density lipoprotein level after the first and second screening (p=0.02 and p=0.01, respectively), but a decrease in mean random glucose level was not statistically significant (p=0.62). Retinal results indicate 28.4% (n=1,482) with a positive/abnormal finding, of which 1.79% (n=93) required immediate referral for sight-threatening retinopathy and 27% (n=1,389) required follow-up of from 3 months to 1 year. CONCLUSIONS: Screening programs are cost-effective and provide value in preventive health efforts. Broad use of screening programs should be considered in healthcare redesign efforts. Community-based screening is an effective strategy to identify health risk, improve access, provide motivation to change health habits, and improve physical status while returning significant value.