Serum sialic acid concentration in children and adolescence with insulin dependent diabetes mellitus [IDDM]

ABSTRACT

It is well established that total serum sialic acid [TSA], a potent cardiovascular risk factor, is elevated in patients with type 2 diabetes mellitus [NIDDM] compared to non diabetics. However, it is not clear whether TSA is elevated in type I diabetic patients [IDDM]. The study included 32 children and adolescence with insulin dependent diabetes mellitus [IDDM], 19 males and 13 females, their ages were 14.8 +/- 2.7 years [8-19 years] with a diabetes duration of 7.3 +/- 2.9 years [3-12 years]. A group of 15 age and sex matched controls were studied, 9 males and 6 females, their ages were 14.5 +/- 2.5 years [9-18 years]. Fasting blood samples were taken for assessment of fasting blood glucose, glycated haemoglobin [HBAIc], serum cholesterol, serum creatinine and serum sialic acid, as was a first morning urine sample for assessment of microalbuminuria. Fasting blood glucose and serum sialic acid were estimated in the control group. Serum sialic acid was significantly elevated in diabetic patients compared to controls [91.8 +/- 27.6 mg/dl v.s 70.3-7 mg dl, P < 0.001]. 9 out of 32 diabetic patients had microalbuminuria, their serum sialic acid was significantly elevated compared to normoalbumi nuric diabetics [193.1 +/- 37.1 mg/dl v.s 81 +/- 11.9 mg/dl, P = 0.002]. Serum sialic acid correlated significantly with HBA1c [r = 0.49, P = 0.004] and serum cholesterol [r = 0.50, P = 0.003]. A weak correlation existed be tween serum sialic acid and fasting blood glucose [r = 0.36, P = 0.039], serum creatinine [r = 0.42, P = 0.016] and age [r = 0.44, P = 0.010]. In a multiple regression analysis including fasting blood glucose, HBAIc, creatinirte, cholesterol, age, diabetes duration, systolic and diastolic blood pressure and microalbuminuria, it was found that microalbuminuria was the only variable which affected the levels of sialic acid. It is concluded that serum sialic acid is elevated in IDDM patients and is further increased in diabetic patients with microalbuminuria. Whether serum sialic acid is predictive for early nephropathy and cardiovascular disease in IDDM has to be shown in the future