Syndemic effects of social isolation on mental health, health behaviours and diabetes management in older adults with diabetes: a gender-based cross-sectional study in South Korea

OBJECTIVES: To examine the associations between social isolation (SI) and mental health, health behaviours and diabetes management among older adults with diabetes in South Korea, focusing on gender-specific syndemic patterns. DESIGN: Cross-sectional secondary analysis. SETTING: 2023 Korea Community Health Survey, a nationwide community-based survey. PARTICIPANTS: 18 924 adults aged ≥65 years with physician-diagnosed diabetes. OUTCOME MEASURES: Mental health (depressive symptoms, perceived stress), health behaviours (smoking, high-risk drinking, physical activity) and diabetes management (medication use, complication screening, diabetes education) were assessed. Multivariable logistic regression was used to estimate the adjusted associations between SI and study outcomes. RESULTS: SI was more prevalent among women (33.6%) than among men (14.1%). In men, SI was associated with depressive symptoms (aOR=1.60, 95% CI 1.18 to 2.18, p=0.003), smoking (aOR=1.51, 95% CI 1.25 to 1.82, p