The effects of high haematocrit levels on glucose metabolism disorders.

There has been only limited research investigating the possible association between raised haematocrit levels, glucose intolerance and type 2 diabetes. In the present study, we explored the association between high haematocrit levels and impaired glucose tolerance by performing oral glucose tolerance tests in 46 patients with chronic obstructive pulmonary disease and no previous history of diabetes mellitus or glucose intolerance. A glucose metabolism disorder was observed in 12 (26%) patients (type 2 diabetes in six patients and impaired glucose tolerance in a further six). There was a significant association between high haematocrit levels and the presence of a glucose metabolism disorder, which was independent of other risk factors. High haematocrit levels may be an independent risk factor for type 2 diabetes and impaired glucose tolerance.