S. K. Cunningham

The relationship of blood glucose and haemoglobin A1 levels in diabetic subjects

Recommendations exist that fasting plasma glucose (FPG) levels can be substituted for glycosylated haemoglobin A, (HbA,) in Type II diabetic subjects (DM II), which have potential important financial implications. The present study was designed to expand this examination and to include Type I DM (DMI) patients and random blood glucose (RBG) values. Data were obtained from 234 DM II and 104 DM I patients, over 3 years. Correlation of HbA1 with FPG levels in DM II yielded an r value of 0.61. Correlation of HbA, with RBG and 2 h post prandial glucose measurements yielded r values of 0.59 and 0.51 respectively, p<0.001. In DM I, similar correlations gave r values ranging between 0.27 and 0.38, p<0.01-0.001.Thus while significant correlations exist between HbA1 and FPG and RBG measurements in both DM I and DM II, clinically applicable information on long-term diabetic control can only be achieved from glucose measurements in DM II but the correlation is not sufficiently tight to recommend substitution of plasma glucose for HbA1 determinations, despite the cost advantages.

Irish endocrine society

LDL oxidation has been implicated as an important atherogenic factor. We have previously shown that the LDL estetified/free cholesterol ratio is different in diabetes. This study examines the effect ofLDL glycosylation on the susceptibility of LDL to in vitro oxidation. In particular it examines whether there is a relationship between LDL cholesterol esterification, LDL glycosylation and the susceptibility to oxidation. LDL was isolated by sequential ultracentrifugation from normoc holesternlaemic (n=l 0, serum cholesterol 5.30-+0.18mmol/ 1 ) and hypercholesterolaemic diabetic patients(n=7 serum cholesterol 7.18_+0.2mmol/1) and normocholesterolaemic control subjects (n=10, serum cholesterol 5.14_+0.28mmo1/1). LDL glycosylation was determined using aminophenylborate gel chromatography and LDL composition was determined. The susceptibility of LDL to oxidation in the presence of CuS04 was assessed by measuring thiobarbituric reactive substances (TBARS) LDL from the hypercholesterolaemic diabetic patients was more rapidly oxidised, TBARS at 1, 2, 3 and 4 hours being 12.6+3.7, 24.5+3.3, 38.4+2.3, and 40.0_+2.1 nmol/mg LDL protein compared with 4.8_+0.6,16.0+2.5, 24.5+9.5, and 32.4+2.1 for LDL from control subjects (p<0.05). Oxidation of LDL from the normocholeslerolaemic diabetic patients of 6.3_+0.7, 18.4=[_,0.3, 34.0+2.4 and 37.2+2.1, nmol/mg LDL protein, was also significantly greater than that from controls (p<0.05). The esterified/free cholesterol ratio correlated positively with the susceptibility of the LDL to oxidation (p<0.05) which was also related positively to the degree of LDL glycosylation (p<0.01). These results suggest a mechanism which would account for the increased accumulation of cholesterol in the atherosclerotic plaque of the normocholesterolaemic diabetic patient.

A role for a non-androgenic anovulant in the management of hirsutism

Sixty-nine patients who had Ferriman/Gallwey hirsutism scores (FG) of ≥8 were treated with Diane, an anovulant containing cyproterone acetate, 2 mg, an anti-androgenic progesterone and ethinyl oestradiol, 5.0 μg. Twenty-one of these had been previously treated with dexamethasone (DEX) and did not respond, i.e. FG >50% of pre-treatment value. Prior to Diane treatment, plasma total testosterone (T) values, 1.4±0.5 nmol/l, mean ±S.D., were similar to those in 43 normal women, 1.23±0.3 nmol/1, as were plasma androstenedione levels, 6.8±2.5 and 6.0±1.7 nmol/1 respectively. However, plasma sex hormone-binding globulin (SHBG) values were suppressed being 36.2116 nmol/I in hirsute women and 45.8115 nmol/1 in normal women, p<0.01. The T/SHBG ratio, an index of free testosterone, was elevated in hirsute women, 4.8+4.1, compared to values in normal women, 2.911.0, p<0.001. Following Diane therapy (2-24 months), 73% of patients responded clinically. There was no change in T, but SHBG was increased to 181±54 nmol/1, p<0.001 and T/SHBG was decreased markedly to 0.9±0.4, p<0.001. Androstenedione fell also to 4.8±1.7 nmol/1, p<0.001. The clinical and hormone response to Diane was similar in both DEX-resistant and previously untreated groups. We conclude that Diane is an effective agent in the treatment of hirsutism while it avoids the adverse effects of androgenic progesterone and of high dose cyproterone acetate therapy.