The effects of patient characteristics and geographical region on hospitalization in patients with type 2 diabetes

Aims: The ADVANCE trial recruited participants from 20 countries worldwide. We analyse here regional variations and causes of hospitalization for people with Type 2 diabetes from Asia, Established Market Economies and Eastern Europe. Methods: A cohort analysis examining the effects of region on causes of first hospitalization, and the association of participant characteristics on all-cause first hospitalization across regions, using multivariable (adjusted for clinical, physiological, behavioural and socio-demographic factors) Cox models. Results: Of 11 140 individuals (6407 men), all-cause hospitalization rates were highest in Established Market Economies, followed by Eastern Europe then Asia. Eastern Europe had rates of hospitalization for diabetic causes four times greater than Established Market Economies [multivariable-adjusted hazard ratio 4.02 (95% CI 2.86-5.63)]. There were no significant regional variations in hospitalization rates for cardiovascular disease (P = 0.534), but much lower rates for musculoskeletal and non-specific causes in Eastern Europe [multivariable-adjusted hazard ratio 0.44 (95% CI 0.32-0.60) and 0.19 (95% CI 0.12-0.29)] and Asia [hazard ratio 0.21 (95% CI 0.16-0.29) and 0.09 (95% CI 0.06-0.14)] compared with Established Market Economies. In all regions, participants hospitalized for any cause were more likely to be older, male, hypertensive, smokers, have higher glycated haemoglobin and a history of macrovascular or macrovascular disease. Conclusions: Across three markedly different regions of the world, regional rates and causes of hospitalization varied widely in patients with Type 2 diabetes. Adjustment for a range of patient characteristics did not explain these regional differences in hospitalization, which appear to be attributable to health system factors.