Association between income levels and irregular physician visits after a health checkup, and its consequent effect on glycemic control among employees: A retrospective propensity score-matched cohort study

Aims/Introduction: The present study aimed to evaluate the effects of income levels on physician visit patterns and to quantify the consequent impact of irregular physician visits on glycemic control among employees’ health insurance beneficiaries in Japan. Materials and Methods: We obtained specific health checkup data of untreated diabetes patients from the Fukuoka branch of the Japanese Health Insurance Association. We selected 2,981 insurance beneficiaries and classified 650 and 2,331 patients into, respectively, the regular visit and irregular visit group. We implemented propensity score matching to select an adequate control group. Results: Compared with those with a standard monthly income <$2,000 (US$1 = ¥100), those with a higher monthly income were less likely to have irregular visits; $2,000–2,999: odds ratio 0.74 (95% confidence interval 0.56–0.98), $3,000–3,999: odds ratio 0.63 (95% confidence interval 0.46–0.87) and ≥$5,000: odds ratio 0.58 (95% confidence interval 0.39–0.86). After propensity score matching and adjusting for covariates, the irregular visit group tended to have poor glycemic control; increased glycated hemoglobin ≥0.5: odds ratio 1.90 (95% confidence interval 1.30–2.77), ≥1.0: odds ratio 2.75 (95% confidence interval 1.56–4.82) and ≥20% relatively: odds ratio 3.18 (95% confidence interval 1.46–6.92). Conclusions: We clarified that there was a significant relationship between income and irregular visits, and this consequently resulted in poor glycemic control. These findings would be useful for more effective disease management.