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reduced blood sugar level (both fasting and post prandial). All the subjects of this study taking oral antidiabetic drugs or less than 40 units of insulin daily were relieved of the necessity of medication. These findings again support the results of the present study.
Glycosylated haemoglobin concentration significantly predicted mortality, with increasing risk throughout the whole range of concentrations, even below the threshold commonly accepted for diagnosis of diabetes. This effect was independent of known risk factors and consistent after men with existing diabetes, heart disease, and stroke were excluded. The predictive value of HbA, for total mortality was stronger than that documented for cholesterol concentration, body mass index, and blood pressure. The mortality risk of establishing diabetes seemed to be mediated largely through HbA, concentration.
People with diabetes have increased risk of vascular and respiratory diseases 29,30,31,32 and in these people blood concentration of glucose or HbA, predicts subsequent microvascular and macrovascular events.33,34 High glucose concentrations might accelerate atherosclerotic processes through several plausible mechanisms such as oxidative stress and protein glycation of vessel walls.35 Reductions in blood glucose or HbA. concentrations through tight blood glucose control in people with diabetes also reduces the risk of microvascular disease. 36-39 However, whether the relation of increasing blood glucose with adverse clinical outcomes exists only above a thresholdor is a continuous relation across the whole population distribution is still debated. 40-46 For microvascular complications, studies report a flat relation below a threshold for fasting and post prandial glucose concentration as well as for HbA,,.47 The relation with macrovascular outcomes, coronary heart disease, and stroke, is less clear. 40-46 It has been concluded that the progressive relation between glucose concentrations and cardiovascular and respiratory diseases extends below the diabetic threshold.
HbA, concentration is related to prevalent coronary disease or carotid intimal thickening in non-diabetic people.48.49 Two prospective studies reported that HbA, predicts cardiovascular disease in non-diabetic people, but they focused on the top end of the distribution, which may contain people with undiagnosed diabetes.50,51 Glycosylated haemoglobin seems to resemble blood pressure and blood cholesterol in terms of the
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