# Regional Differences and Similarities in Diabetes Care in Japan: Insights from the J-DOME Registry

## TL;DR

The study found no regional differences in diabetes care in Japan but found better management by diabetes specialists compared to non-specialists.

## Contribution

The study is novel in comparing diabetes care by specialists versus non-specialists using nationwide registry data in Japan.

## Key findings

- No significant regional differences in glycated hemoglobin or blood pressure levels were found across Japan.
- Diabetes specialists had significantly higher rates of regular ophthalmologic visits and urinary albumin testing compared to non-specialists.
- Specialists showed better adherence to recommended diabetes management practices than non-specialist physicians.

## Abstract

Comparing diabetes care across different regions of Japan is essential for informing future healthcare policy. Additionally, since many patients with diabetes receive treatment from non-specialist physicians, it is important to determine whether differences exist between diabetes specialists and non-specialists in terms of medical care and to identify specific areas, if any, where these differences occur.

To investigate this, we utilized data from J-DOME (Japan Medical Association Database of Clinical Medicine), a patient registry established as a nationwide project by the Japan Medical Association. Patients with type 2 diabetes were categorized into seven regional groups based on Japan’s prefectural divisions, and a regional comparison was conducted. Differences between specialists and non-specialists were also examined.

A total of 116 medical institutions encompassing 2,938 patients were included in the analysis. The nationwide mean glycated hemoglobin level was 6.96% (standard deviation [SD]: 0.46), with no statistically significant regional variations. Similarly, the nationwide mean blood pressure was 129.7/73.0 mmHg (SD: 6.1/5.7 mmHg), with no significant regional differences observed.

The average rates of regular ophthalmologic visits and urinary albumin quantification testing were 63.7% (SD: 31.3) and 40.2% (SD: 38.4), respectively. These rates were significantly higher in institutions led by diabetes specialists compared to those managed by non-specialists (regular ophthalmologic visit rate: non-specialists institutions: 53.9% [SD: 33.8]; diabetes specialist institutions: 78.5% [SD: 19.5], p < 0.001; urinary albumin quantification test rate among patients without macroproteinuria: non-specialist institutions: 33.5% [SD: 39.0]; diabetes specialist institutions: 62.5% [SD: 35.5], p < 0.001).

This survey revealed no significant regional differences in diabetes care. However, certain aspects of diabetes management differed significantly between diabetes specialists and non-specialist physicians.