SUMMARY. We have studied the relationship between serum glucose and urate in 260 699 men and 214 118 women from Sweden, and 140084 men and 30653 women from the UK. We found an increase in mean serum urate with increasing glucose concentrations up to 7'OmmollL in men and 9'OmmollL in women. Thereafter increasing glucose values were accompanied by a statistically significant decrease in urate concentrations. This fall was particularly marked in younger subjects. We believe this may have important implications for the free radical status of diabetics.
Additional key phrases: diabetics; glycosuria; free radicalsRelationships between serum urate and glucose in patients with diabetes have been reported over three decades.l " All the authors conclude that in diabetes the serum urate concentration is reduced. Moreover, higher urate concentrations in prediabetic compared with non-diabetic subjects have also been reported." This work was indirectly confirmed by Cook et al.,5 who showed that in a population study of men the mean urate concentrations increased with increasing mean glucose concentration until a mean glucose of approximately 8 mmollL was reached, after which the urate value did not increase further. Then as the mean glucose value increased above 10 mmollL there was a significant decrease in urate concentrations. They postulated that the fall in urate concentrations occurred when the serum glucose concentration rose to a value which resulted in glycosuria. It has been shown in healthy volunteers" that if the serum glucose is raised above that sufficient to cause glycosuria, then urinary urate is directly proportional to the urinary glucose.
METHODSTo study this problem we have been able to use large data bases of laboratory results from Sweden and the UK. The Swedish results were from a group of patients numbering 260 699 men and 214118 women. Most of the specimens Correspondence: Dr Ann Hale.analysed were from subjects having routine health assessments but some were from known diabetics. There were 9415 (3 '60/0) men with serum glucose concentrations of 7· 5 mmollL or greater. The corresponding figure for women was 4048 (1' 9%).The patients in the UK study were attending the BUP A Health Screening Centres in London, the analyses being carried out by J S Pathology Pic (London, UK). The results from 140084 men have been analysed and 1936 (1'4%) had serum glucose concentrations of at least 7· 5 mmollL. The corresponding figure for women was 30653 of whom 220 (0' 7%) had a serum glucose of 7· 5 mmollL or greater.The specimens were separated within 1 h of collection. The serum glucose method using glucose oxidase was the same in both countries, but the urate methods were different. In the UK the phosphotungstic acid method was used, employing the SMAC II analyser of the Technicon Company (Basingstoke, UK) and in Sweden the uricase method marketed as a diagnostic kit by Boehringer Mannheim (Tutzing, Germany) was used, the apparatus employed being a PRISMA Multichannel Analyser (New Clinicon, Stockholm, Sweden). We ...