Influence of endogenous hyperinsulinism on high density lipoprotein2 level in type 2 (non-insulin-dependent) diabetes mellitus and impaired glucose tolerance

We determined the insulin response to an oral glucose ingestion and levels of serum lipoproteins in 25 untreated patients with type 2 diabetes mellitus, in 26 subjects with impaired glucose tolerance (IGT), and in 35 non-diabetic control subjects. The three groups had similar compositions with respect to age and sex distribution. The levels of VLDL triglyceride in the subjects with type 2 diabetes or IGT were higher than those in controls. Serum HDL- and HDL2 cholesterol were significantly decreased in type 2 diabetics, and the subjects with IGT showed a similar tendency. Serum apolipoprotein A-II levels were lower in the male subjects with type 2 diabetes or IGT than in controls. Insulin response, i.e., sum of immunoreactive insulin (IRI) levels at basal, 30, 60, 90 and 120 min after a 75-g oral glucose load, negatively correlated to HDL- and HDL2 cholesterol levels (r = -0.396, P less than 0.05; r = -0.482, P less than 0.001, respectively), and positively correlated to VLDL triglyceride values (r = 0.485, P less than 0.001) in the male subjects with type 2 diabetes or IGT. In the female subjects, fasting plasma IRI values significantly correlated to HDL cholesterol (r = -0.496, P less than 0.05). There was a significant negative correlation between the concentrations of HDL2 cholesterol and VLDL triglyceride. These data show that lipoprotein metabolism, not only in type 2 diabetics, but also in IGT tends to show changes such as decreased HDL2 cholesterol and increased VLDL triglyceride levels, and which might be related to the hypersecretion of endogenous insulin.

Hyperlipoproteinaemia in primary gout: hyperlipoproteinaemic phenotype and influence of alcohol intake and obesity in Japan

Serum lipoprotein profiles were investigated in 108 male patients with primary gout before treatment to elucidate the prevalence of each individual phenotype of coexisting hyperlipoproteinaemia and pathogenic factors responsible for it. The mean serum triglyceride (TG) and total cholesterol (TC) levels in the patients with gout were 2.10 +/- 0.14 mmol/l and 5.26 +/- 0.10 mmol/l (mean +/- SEM) respectively, which were significantly higher (p less than 0.01 and p less than 0.05 respectively) than the levels in age matched controls without gout (1.30 +/- 0.07 mmol/l and 4.77 +/- 0.08 mmol/l respectively). Serum high density lipoprotein cholesterol (HDL-C) values were slightly decreased in patients with gout compared with controls (1.24 +/- 0.08 mmol/l v 1.40 +/- 0.03 mmol/l, p less than 0.05). Hyperlipoproteinaemia was seen in 61 patients (56%), of whom patients with type IIa, IIb, and IV hyperlipoproteinaemia formed 13, 15, and 69% respectively. Thus the prevalence of type IV hyperlipoproteinaemia was high in primary gout as compared with primary hyperlipoproteinaemia with primary hyperlipoproteinaemia (69% v 43%, p less than 0.01). The independent and relative influences of clinical data of the patients upon the concentrations of serum lipids were assessed by stepwise multiple regression analysis. Two major predictors of serum TG level were alcohol intake (p less than 0.01) and serum uric acid level (p less than 0.05). The most significant predictive variable was alcohol intake, but its influence was judged to be small (r2 = 0.067). None of the other variables, including obesity index, had any significant influence. The relationships between any of these variables and serum TC or HDL-C levels were not significant. In addition, serum lipid levels were investigated in patients with neither obesity (defined as 120% or more of ideal body weight) nor a history of alcohol intake. Their serum TG and TC concentrations were also significantly higher than the respective control levels. Thus hyperlipoproteinaemia in primary gout its unlikely to be secondary to excess alcohol intake or obesity, or both. Instead, it may result from genetic factors such as a combined hyperlipidaemic trait.