Local authorities in Japan have been used different criteria for diabetes diagnoses in annual medical checkups for elderly people and other local residents, a practice that may lead to misdiagnoses, health ministry officials said Friday.

The Ministry of Health, Labor and Welfare is planning to consider unifying the criteria and seek expert advice, they said.

A survey the health ministry conducted in Aichi Prefecture in 2001 found that 38 municipalities there depend on the health ministry criteria in diagnoses using blood-sugar levels, 25 on hospital-adopted criteria, and 11 on the Japan Diabetes Society criteria, they said.

Kyodo News has also found that the health ministry criteria are adopted in Sapporo and Sendai, the Diabetes Society criteria in Kyoto, and a local medical society's criteria in Hiroshima.

About 12 million people receive annual diabetes tests organized by local authorities across the country.

Under the health ministry criteria, the minimum fasting blood-sugar level for recommending medical treatments is 140 milligrams per deciliter of blood, and 126 mg/dL under the Diabetes Society criteria.

The health ministry survey found that the blood-sugar level ranges from 116 mg/dL to 200 mg/dL in diabetes tests performed in Aichi, the officials said.
The local authorities in Aichi might have refrained from changing their blood-sugar criteria in order to maintain continuity of data, they said.

The health ministry survey team warns that loose criteria could allow diabetes to be left untreated and that diagnosis results could change if a person moves from one city to another, they said.