Genetic and metabolic risk factors for the development of late complications in type I (insulin-dependent) diabetes

Apolipoprotein profile in type II diabetic patients with and without coronary heart disease

Diabetes mellitus is frequently associated with lipid metabolism abnormalities. In the present study the lipid and apolipoprotein profiles have been compared in type II diabetic subjects with (n = 30) and without (n = 30) coronary heart disease (CHD). All subjects were studied after good metabolic control had been achieved. Significant differences in plasma lipids and apolipoproteins were seen in diabetic patients with CHD in comparison with diabetics without CHD. Patients with CHD presented higher total cholesterol, triglyceride, LDL-cholesterol, apo B, apo CII and apo CIII levels and total cholesterol/HDL-cholesterol and LDL-cholesterol HDL-cholesterol ratios and lower HDL-cholesterol values and apo A1/apo B ratio than the patients without CHD. The same findings were found in females; while male subjects with CHD had significantly increased total cholesterol, LDL-cholesterol and apo B levels and total cholesterol/HDL-cholesterol and LDL-cholesterol/HDL-cholesterol ratios and significantly decreased apo A1/apo B ratio compared with males without CHD. These findings support the concept that the apolipoprotein profile plays a remarkable role as risk factor for CHD in type II diabetes mellitus.

Association of coronary heart disease with serum lipid and apolipoprotein concentrations in long-term diabetes. Results of the Erfurt study

The Erfurt study is concerned with the follow-up of all the 208 long-term diabetics out of the closed area of the Erfurt district with an at least 20 years' diabetes survival in 1970. In 1980 risk factors for coronary heart disease (CHD) were assessed in 71 (85% type I diabetes) out of 76 patients still alive. Progression of CHD within the subsequent five years (death due to CHD in 8 cases and progression of the ECG findings according to the Minnesota code in 3 cases) was associated with older age, lower body mass index, higher triglycerides, and a higher total cholesterol/HDL cholesterol ratio in comparison with the surviving patients without progression (n = 41). No significant differences could be found with regard to sex distribution, age at diabetes onset, duration of diabetes, percentage of type I diabetes, systolic and diastolic blood pressure, smoking behavior, prevalence of nephropathy, glycemic control, and serum levels of total cholesterol, LDL cholesterol, and HDL cholesterol. The subsequent reinvestigation in 1985 also included the determination of apolipoproteins. Since type II diabetes was not equally distributed, only type I diabetics were considered for the comparison of patients with ECG findings suggestive of CHD (n = 5) with the remaining subjects (n = 35). In addition to the above mentioned differences, CHD in long-term type I diabetes was also accompanied by lower HDL cholesterol, lower apolipoprotein A-I, and a higher apolipoprotein B/apolipoprotein A-I ratio. Substantially similar differences could be observed when type II diabetics were not excluded (10 patients with and 37 patients without CHD). It is concluded that the lipoprotein pattern is important for the survival in long-term diabetes.

Lipoprotein pattern in long-term diabetes of an at least 35 years' duration. Results of the Erfurt Study

All diabetic patients suffering from the disease for at least 20 years and living in the closed area of the Erfurt district in 1970 have been followed prospectively since that time. In 47 of them still alive in 1985, i.e. after more than 35 years of diabetes, serum lipid and apolipoprotein concentrations were measured and compared to those of non-diabetic subjects without cardiovascular diseases (n = 47) pair-matched by sex, age, and body weight. In males (n = 27) significantly (p less than 0.01) higher levels of HDL cholesterol and apolipoprotein A-I as well as lower concentrations of triglycerides and a lower total cholesterol/HDL cholesterol risk ratio than in nondiabetic control subjects could be found. In long-term diabetic females (n = 20), apolipoprotein A-I levels were also increased (p less than 0.02). Trends in HDL cholesterol and triglycerides were similar to those found in males but did not reach statistical significance. Higher concentrations of total cholesterol (p less than 0.02), LDL cholesterol (P less than 0.05), and apolipoprotein B (p less than 0.02), however, did not fit in with a beneficial lipoprotein pattern. The frequency of pathological lipoprotein patterns was not higher than among the non-diabetic control subjects (32% and 40%, respectively). According to these findings an antiatherogenic lipoprotein pattern might be considered, at least in males, as one of the determinants causing the multifactorial event of long-term survival in diabetes.

Acetylator phenotypes in diabetes mellitus

The purpose of this study was to establish the correlation between the genetically determined rate of acetylation of certain drugs and the development of diabetic neuropathy. Acetylator phenotype was determined according to Evans in 100 healthy individuals and 160 diabetics including 80 patients with type I and 80 with type II diabetes. The diagnosis of diabetic neuropathy was based on clinical neurological examination. In addition, electrostimulation was carried out in 49 diabetics. Among the healthy controls, the fast acetylator phenotype was found in 44 cases (44%) and the slow one in 56 (56%). In type I diabetes these values were 51 (64%) and 29 (36%), in type II 46 (58%) and 34 (42%), respectively. The predominance of fast acetylators in type I diabetes was statistically significant (p less than 0.01) when compared to the healthy population of Warsaw. However, no significant correlation was found between diabetic neuropathy and the distribution of acetylator phenotype. Further prospective studies are necessary in order to ascertain whether the acetylator phenotype might be considered a genetic marker of type I diabetes.