Living alone is associated with visit-to-visit HbA1c variability in men but not in women in people with type 2 diabetes: KAMOGAWA-DM cohort study

The purpose of this study was to evaluate the association between living alone and glycemic parameters, especially glycemic variability, in men and women with type 2 diabetes. Lifestyle factors, including living alone, were assessed by a questionnaire in this cross-sectional study. Average, standard deviation (SD), and coefficient of variation (CV) of HbA1c were calculated using the values of HbA1c, which were extracted from the medical record for 1 year. Eighteen percent of men (35/198) and 17% of women (18/103) were living alone. In men, the average of HbA1c (59.9 mmol/mol [11.0] vs. 55.7 mmol/mol [9.1], 7.6% [1.0] vs. 7.2% [0.8], p = 0.018), and CV of HbA1c (0.06 [0.03–0.08] vs. 0.03 [0.02–0.05], p < 0.001) were all significantly higher in men who were living alone than in men who weren’t. However, there were no differences in the average (53.2 mmol/mol [11.4] vs. 56.0 mmol/mol [8.8], 7.0% [1.0] vs. 7.3% [0.8], p = 0.252) or CV (0.03 [0.02–0.05] vs. 0.03 [0.02–0.04], p = 0.845) between women who were living alone and women who weren’t. Multiple regression analyses revealed that living alone was associated with CV of HbA1c after adjusting for covariates in men (β = 0.180, p = 0.005), but not in women (β = 0.085, p = 0.369). We showed that living alone is associated with visit-to-visit HbA1c variability in men, but not women, with type 2 diabetes. In clinical practice, it is necessary to pay attention to glycemic control in men who are living alone.