GLYCOSYLATED HÆMOGLOBIN CONCENTRATIONS AND CLINITEST RESULTS IN INSULIN-DEPENDENT DIABETES
RANK-CORRELATION COEFFICIENTS, r,
LEVELS AND DIFFERENT MEASUREMENTS OF
J. SORIA C. SORIA
R. LANOE N. THIBULT E. ESCHWEGE
Departments of Diabetes and Hœmatology, Hôtel-Dieu Hospital and Pierre and Marie Curie University, Paris, Unité de Recherches Statistiques, INSERM, Villejuif, France, and Central Laboratories of Biochemistry and Hœmatology, Lariboisière Hospital, Paris, France
insulin-dependent diabetic outpatients, hæmoglobin AIc (HbAIc) was measured by an electrofocusing method. Diabetic control was evaluated by the semiquantitative urine test for sugar, ’Clinitest’, three times a day every day in the 8 weeks before the HbAIc determination. 24-hour glycosuria and fasting and postprandial blood-glucose levels were measured one to five times during this period. The HbAIc concentration correlated highly with the semiquantitative urinary-sugar-concentration index but not
with the other parameters. Introduction GLYCOSYLATED haemoglobin concentrations (HbAIC) in the blood are higher in diabetic than non-diabetic patients.1-4 An inverse correlation has been established between HbAIC concentrations and the quality of control of diabetes in the 2 months before HbAIC determination,5-8 but no correlation was found with a single bloodsugar measurement.3 We investigated insulin-dependent diabetic patients to see if there was a relation between HbAIC concentrations and diabetic control judged by a thrice-daily semiquantitative estimation of urinary sugar excretion.
Methods 11 insulin-dependent diabetic patients were selected from the Hotel-Dieu Hospital diabetic clinic. They were known to be reliable regular outpatients. The degree of diabetic control was evaluated by the patients themselves with ’Clinitest’ (Miles Laboratories, Ames Division, France), a rapid method of testing the urine for sugar. The patient matched the urine sample against a colour chart with a scale ranging from 0 to
*For abbreviations see text. N.s.=not
4, three times
a day. As suggested by Koenig,8 these measuresummed and mean daily indices were calculated (u.G. index before breakfast, before lunch, before dinner, total each day) during the 8 weeks before the blood-Sampling for HbAIc determination. In addition, the percentages of negative tests for sugar were calculated (N.U.G. percentages). One or more 24-hour glycosuria and blood-glucose levels, fasting (F.B.G.) and postprandial (P.P.B.G.) (at 2 P.M.), were also measured during this period. HbAi,, concentrations were determined by Jeppsson’s method9 as modified by Krishnamoorthy et al. 10 by electrofocusing. After the band HbAIc was separated by electrofocusing, the HbAIc and remaining haemoglobins were eluted separately. The benzidin and perhydrol method" was then used to measure the percentage of HbAIc.
in table I. Because the degree of control of diabetes showed non-normal distribution, and because the number of subjects was small, we used Spearman’s rank-correlation coefficient12 to evaluate the relation between HbAIC levels and diabetes control (table II). Strong correlations were found between HbAIC concentrations and urinary glucose indices: all the coefficient values were at least 0.65 and highly significant (P