[Smoking and diabetes mellitus].

The prevalence of smokers among patients with diabetes is found to be lower than in the population as a whole. Diabetic patients have increased morbidity and mortality from cardiovascular diseases and, in the majority of investigations, smoking is found to be a risk factor in this relationship which does not differ quantitatively from that found in non-diabetics. On the basis of the literature, it has not proved possible to quantitate smoking as a risk factor for the development of peripheral arteriosclerotic vascular disease. Smoking involves hormonal and metabolic changes which are of particular interest in relation to diabetes mellitus. Thus, smoking stimulates the secretion of the antiinsulin hormones, particularly catecholamines, resulting in subcutaneous vasoconstriction which may be unfortunate as it influences insulin absorption. Patients who smoke do not, however, appear to present poorer glycaemic control than non-smokers. A few investigations have shown that smokers have greater insulin requirements than non-smokers. In type 1 (insulin-dependent) diabetes, there is evidence to suggest that diabetic nephropathy and proliferative retinopathy occur more frequently in smokers than in non-smokers. Smoking aggravates the pre-existing more pronounced osteoporosis which occurs in female insulin-dependent patients. It is therefore advantageous to advise diabetic patients against smoking from the point of view of diabetes as such.