Katarzyna Homa

Low predictive value of traditional risk factors in identifying women at risk for gestational diabetes

Background. There is no worldwide agreement on the best way to screen for gestational diabetes mellitus (GDM), and different diagnostic methods have been developed in order to identify women at risk. The aim of this study was to evaluate the prevalence and predictive value of the traditional risk indicators for GDM in a large group of Caucasian women. Methods. We evaluated the frequency distribution of age, body mass index (BMI), prior macrosomia, prior GDM, and family history of diabetes of 1,414 pregnant women with GDM and 1,011 healthy pregnant women. Results. The distribution of risk factors in both groups was different and significantly higher in GDM women. The cut‐off value for age was 28years, and 23kg/m2 for BMI. The accumulation of two or more risk factors was frequent in GDM, but not in healthy women. By multiple logistic regression, there were significant interactions between independent variables of interest and GDM (OR: 3.19; p<0.001; sensitivity: 57.9%, specificity: 69.8%). The strongest predictors were prior GDM (OR: 4.35; 95% CI: 2.42–7.82) and a family history of diabetes (OR: 3.03; 95% CI: 2.47–3.72); less predictive were age (OR: 1.69; 95% CI: 1.44–1.99), BMI (OR: 1.50; 95% CI: 1.28–1.77), and prior macrosomia (OR: 1.64; 95% CI: 1.19–2.26). Conclusions. Selective screening based on traditional risk factors for GDM had relatively low sensitivity, and identified <60% of Caucasian women at risk. The cut‐off value for BMI as a risk indicator (23kg/m2) was lower than that proposed by guidelines about screening for GDM.

The Common C49620T Polymorphism in the Sulfonylurea Receptor Gene SUR1 (ABCC8) in Patients with Gestational Diabetes and Subsequent Glucose Metabolism Abnormalities

Aim. The aim of this study is to investigate the relationship between the common C49620T polymorphism in the sulfonylurea receptor (SUR1) gene and glucose metabolism, β-cell secretory function and insulin resistance in women with a history of gestational diabetes (GDM). Material and Methods. Study group included 199 women, diagnosed GDM within the last 5–12 years and control group of comparable 50 women in whom GDM was excluded during pregnancy. Blood glucose and insulin levels were measured during oral glucose tolerance test. Indices of insulin resistance (HOMA-IR) and β-cell function (HOMA %B) were calculated. In all patients, the C49620T polymorphism in intron 15 of the SUR1 gene was determined. Results. The distribution of the studied polymorphism in the two groups did not differ from each other (χ 2 = 0.34, P = 0.8425). No association between the distribution of polymorphisms and coexisting glucose metabolism disorders (χ 2 = 7,13, P = 0, 3043) was found. No association was also observed between the polymorphism and HOMA %B or HOMA-IR. Conclusions. The polymorphism C49620T in the SUR1 gene is not associated with insulin resistance and/or insulin secretion in women with a history of GDM and does not affect the development of GDM, or the development of glucose intolerance in the studied population.

False diagnosis of type 1 diabetes mellitus and its complications in Wolfram syndrome--is it the reason for the low number of reported cases of this abnormality?

Wolfram syndrome (WS), also known as DIDMOAD (Diabetes Insipidus, Diabetes Mellitus, Optic Atrophy and Deafness), is a rare autosomal recessive syndrome (1/770,000 in the United Kingdom), characterised by juvenile onset of diabetes mellitus, optic nerve atrophy, diabetes insipidus, sensorineural deafness, renal tract and neurological abnormalities, and primary gonadal atrophy. WS is caused mainly by biallelic mutations in the WFS1 gene, which encodes wolframin. Wide tissue distribution of wolframin and many mutations in the wolframin gene resulting in Wolfram syndrome may contribute to different phenotypes and the unusual combinations of clinical features. We describe a female patient with Wolfram syndrome diagnosed at the age of 25, with a previous false diagnosis of type 1 diabetes mellitus and misdiagnosed diabetic complications. The patient was found to be a compound heterozygote for two novel mutations in exon 8 of WFS1 gene: a 2-bp deletion AT at nt 1539 leading to a frameshift (Y513fs) and a single-base substitution 1174C > T resulting in a stop codon (Q392X). A detailed analysis of the patients medical history and a review of the literature suggest that many cases of Wolfram syndrome may remain undiagnosed due to misdiagnosis as type 1 diabetes mellitus and incorrect interpretation of clinical symptoms of neurodegenerative abnormalities, especially in their early stages.

Women with normal glucose tolerance and a history of gestational diabetes show significant impairment of β-cell function at normal insulin sensitivity

OBJECTIVE Although the nature of gestational diabetes mellitus (GDM) remains unclear, the condition is thought to be related primarily to insulin resistance, overweight and obesity. Most studies include women with a history of GDM and later carbohydrate metabolism abnormalities, while reports of women with previous GDM and subsequent normoglycaemia are scarce. The aim of this study was to assess insulin resistance and β-cell function in normoglycaemic women with a history of GDM. MATERIALS AND METHODS The study group included 199 women, aged 38.4±6.6 years, diagnosed with GDM within the last 5-12 years [GDM(+)] and a control group of 50 comparable women in whom GDM was excluded [GDM(-)], according to WHO criteria. Blood glucose and insulin levels were measured at the beginning (fasting) and at 60 and 120min of oral glucose tolerance tests. Indices of insulin resistance (HOMA-IR), insulin sensitivity (HOMA-S%) and β-cell function (HOMA-B%) were calculated. RESULTS Normoglycaemia was observed in 57% of GDM(+) and 88% of GDM(-) women (P=0.0003). Diabetes was diagnosed in 13 (6.5%) GDM(+) women and in none of the GDM(-) women. Comparison of 113 normoglycaemic GDM(+) and 44 normoglycaemic GDM(-) women revealed significantly impaired β-cell function (HOMA-B%: 131.1±51.1 vs 144.7±47.1, respectively; P=0.038) with similar normal body mass index (BMI) and no differences in HOMA-IR and HOMA-S%. CONCLUSION In this study, more than half of the GDM(+) women were presented with normal glucose tolerance. However, despite normoglycaemia, women with a history of GDM were characterized by significantly impaired insulin secretion, but no signs of increased insulin resistance.