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OBJECTIVE To evaluate cardiac mass and function, carotid intima-media thickness, and serum lipid and lipoprotein (a) (Lpa) levels in children and adolescents with type 1 diabetes mellitus (DM) of short duration. BACKGROUND Diabetes mellitus has been found to be an important risk factor for macrovascular disease in adults. Increased serum lipids and Lpa levels have been reported in adolescents with type 1 DM; atherosclerotic vascular lesions involving a combination of fatty degeneration and vessel stiffening of the arterial wall and myocardial involvement impairing diastolic function may be present in adolescents and young adults with type 1 DM. DESIGN/METHODS Twenty children and adolescents (10 males, 10 females) diagnosed with type 1 DM before 3.4 +/- 3.3 years with a mean age of 11.9 +/- 3.6 years were studied; their HbA1c levels were 8.0 +/- 1.9%. Twenty healthy non-diabetic controls, 10 males and 10 females, aged 12.1 +/- 3.4 years, matched for height and weight, participated in the study. Fasting blood samples were obtained for lipid and Lpa analysis. Patients underwent transthoracic M-mode and two-dimensional echocardiographic evaluation for measurement of left atrial and ventricular dimensions and left ventricular (LV) wall thickness and mass. Stroke volume and cardiac output were measured using pulsed Doppler echocardiography; carotid intima-media thickness was measured using high-resolution mode B ultrasound. RESULTS Interventricular septal thickness (7.1 +/- 1.8 vs 7.0 +/- 1.5 mm), LV posterior wall thickness (7.1 +/- 1.4 vs 7.5 +/- 2.0 mm) and LV mass after correction for body surface area (70.6 +/- 27.4 vs 70.7 +/- 18.0 g/m2) were similar in patients and controls. Similarly, the LV ejection fraction at rest was similar in patients and controls (69.9 +/- 2.3 vs 70.0 +/- 0.6%), as were pulmonary venous flow velocities (0.56 +/- 0.09 vs 0.55 +/- 0.10 m/s for diastolic peak velocity, 0.54 +/- 0.08 vs 0.50 +/- 0.09 m/s for systolic peak velocity and 0.17 +/- 0.07 vs 0.19 +/- 0.05 m/s for atrial reversal filling). Carotid intima-media thickness (0.60 +/- 0.02 and 0.59 +/- 0.02 mm for the right and left carotid artery) was similar to that of controls (0.60 +/- 0.03 and 0.61 +/- 0.02 mm for the right and left carotid artery). Low density lipoprotein cholesterol and Lpa levels were increased in patients compared to controls (113.2 +/- 26.0 mg/dl and 20.1 +/- 11.7 mg/dl in patients vs 90.4 +/- 14.3 mg/dl and 9.8 +/- 2.9 mg/dl in controls; p

The effects of insulin dependent diabetes mellitus (IDDM) on bone metabolism are still not well defined. We evaluated total bone mineral content (TBMC) and bone mineral density (BMD) at the lumbar spine and femoral neck using dual X-ray absorptiometry in 26 IDDM children (15 M, 11 F) with a mean chronological age of 12.1+/-3.1 yr (range 7.1-14.2 yr). Duration of diabetes was 4.3+/-2.9 yr, with a mean glycosylated hemoglobin of 9.2+/-0.4%. BMD and TBMC standard deviation scores (Z-scores) were determined by comparing our results to controls matched for age, sex and pubertal status. BMD and bone formation and resorption markers were determined at the beginning of the study and after one year of follow up. Mean lumbar spine Z-score was -1.06+/-0.2, with negative values in 24 of 26 children (92.6%); 14/26 patients (53.8%) had a lumbar spine Z-score >1.0 SD below the mean. Mean lumbar spine Z-score remained unchanged after one year of follow up (-1.02+/-0.3). No significant differences were obtained in femoral neck BMD or TBMC between groups. No correlation was observed between lumbar spine BMD Z-scores and duration of IDDM or degree of diabetes control, as assessed by the mean glycosylated hemoglobin. Daily urinary calcium excretion was elevated in our patients initially and after one year of follow up; however, no correlation was obtained between lumbar spine BMD and 24 h urinary calcium excretion. Carboxy-terminal propeptide of type 1 collagen values and levels of urinary cross-linked N-telopeptides of type 1 collagen in the diabetic children were significantly lower than those of the matched controls. Osteoblastic activity as assessed by serum osteocalcin and by the carboxy-terminal propeptide of type I collagen and bone resorption as measured by cross-linked N-telopeptides of type 1 collagen did not correlate with the lumbar spine Z-scores. When IDDM patients were subdivided into males and females and into children with more than or less than 2 yr duration of diabetes since diagnosis, no differences between groups were found. These results suggest that insulin dependent diabetes in children is associated with low bone turnover resulting in a deficit in bone mass which may be manifested as osteopenia in the growing bone. This defect is already present in trabecular bone early on in the disease and seems not to be related to glycemic control.