Factors associated with social isolation and being homebound among older patients with diabetes: a cross-sectional study

Objective We aimed at investigating factors associated with social isolation and being homebound in older patients with diabetes. Design Cross-sectional study. Settings Those undergoing outpatient treatments at Ise Red Cross Hospital, Mie Prefecture. Participants Patients with diabetes aged >= 65 years. Primary and secondary outcome measures Social isolation was defined as indulging in less than one interaction per week with individuals other than cohabiting family members. We defined homebound as going outside home less than once a day. To identify factors associated with social isolation and being homebound, we performed logistic regression analysis. The dependent variable was social isolation or homebound and independent variables were basic attributes, glycaemic parameters, complications and treatment details. Results We analysed 558 cases (320 men and 238 women). Among these, 174 (31.2%) were socially isolated; meanwhile, 87 (15.6%) were homebound. The glycoalbumin/haemoglobin A1c ratio (OR 4.52; 95% CI 1.07 to 19.1; p=0.040) and the Tokyo Metropolitan Institute of Gerontology Index of Competence (TMIG-IC) scores (OR 0.72; 95% CI 0.57 to 0.90; p=0.006) had significant associations with social isolation. TMIG-IC scores (OR 0.78; 95% CI 0.66 to 0.92; p=0.003) and insulin use (OR 4.29; 95% CI 1.14 to 16.1; p=0.031) were associated with being homebound. Conclusion In older patients with diabetes, glycaemic fluctuations and insulin use are associated with social isolation and being homebound, respectively. In addition, a decline in higher level functional capacity is a common factor associated with social isolation and being homebound. Thus, it is important to pay attention to social isolation and being homebound when a decline in higher level functional capacity, increased glycaemic fluctuations and insulin use in older patients with diabetes are observed.