Next- generation sequencing is an effective method for diagnosing patients with different forms of monogenic diabetes.

AIM: Monogenic diabetes (MD) represents 5-7% of antibody-negative diabetes cases and is a heterogeneous group of disorders. METHODS: We used targeted next-generation sequencing (NGS) on Illumina NextSeq 550 platform involving the SureSelect assay to perform genetic and clinical characteristics of a study group of 684 individuals, including 542 patients referred from 12 Polish Diabetes Centers with suspected MD diagnosed between December 2016 and December 2019 and their 142 family members (FM). RESULTS: In 198 probands (36.5%) and 66 FM (46.5%) heterozygous causative variants were confirmed in 11 different MD-related genes, including 31 novel mutations, with the highest number in the GCK gene (206/264), 22/264 in the HNF1A gene and 8/264 in the KCNJ11 gene. Of the 183 probands with MODY1-5 diabetes, 48.6% of them were diagnosed at the pre-diabetes stage and most of them (68.7%) were on diet only at the time of genetic diagnosis, while 31.3% were additionally treated with oral hypoglycaemic drugs and/or insulin. CONCLUSIONS: In summary, the results obtained confirm the efficacy of targeted NGS method in the molecular diagnosis of patients with suspected MD and broaden the spectrum of new causal variants, while updating our knowledge of the clinical features of patients defined as having MD.

Updated 24-year trend of Type 1 diabetes incidence in children in Poland reveals a sinusoidal pattern and sustained increase.

AIMS: To present the incidence trend for Type 1 diabetes in Polish children aged 0-14 years, updated using data collected during 2005-2012, and assess the reliability of the predictive model constructed previously using the 1989-2004 database. METHODS: Children aged < 15 years with newly diagnosed Type 1 diabetes are recorded prospectively (EURODIAB criteria) in several regional registers in Poland. Age- and gender-standardized incidence rates for Type 1 diabetes were calculated per 100 000 persons/year. Incidence rates were analysed in terms of the dependency on age, gender, geographical region and population density. Incidence rate trends over time were modelled using generalized linear models. RESULTS: The mean standardized incidence for 1989-2012 was 12.72 per 100 000 persons/year [95% confidence interval (CI), 11.35 to 14.21]. Over the 24-year observation period, the incidence increased from 5.36 to 22.74 per 100 000 persons/year. The lowest incidence rate was in children aged 0-4 years (8.35, 95% CI 7.27 to 9.57 per 100 000 persons/year). There was no difference between genders, or urban and rural regions. Incidence rates were higher in northern compared with southern Poland [14.04 (95% CI 12.59 to 15.63) vs. 11.94 (95% CI 10.62 to 13.39) per 100 000 persons/year]. The new data corrected the earlier predictive model by changing the estimates of some factors related to patient age, gender and their interactions with the remaining factors. The incidence rate shows periodic 5.33-year fluctuations. The periodicity component allows for a more accurate prediction of the incidence rate over time. CONCLUSIONS: This cohort study reveals a sustained increase in Type 1 diabetes incidence in Polish children aged 0-14 years with regular, sinusoidal fluctuations and a slight levelling off in past few years. It is of concern that are the highest increases in incidence are found in children aged 0-4 years.

Monthly use of a real-time continuous glucose monitoring system as an educational and motivational tool for poorly controlled type 1 diabetes adolescents.

PURPOSE: Experience with the use of real-time continuous glucose monitoring systems (RT-CGMS) in teenagers with type 1 diabetes mellitus (T1DM) is limited. We aimed to assess the possibility of glycaemic control improvement and to characterize the group of adolescents, who may gain long-term benefits from the use of the RT-CGMS. METHODS: Forty T1DM patients, aged 14.6 ± 2.1 years, with diabetes duration 7.4 ± 3.6 years and initial HbA1c 9.3 ± 1.5% were recruited. The analysis was based on one-month glucose sensors use, combined with the thorough family support. Patients were analysed in groups according to baseline HbA1c: below and above 7.5%, and 10.0%. Comparison between patients with or without improvement in HbA1c after 3-month follow-up was also performed. Patients' satisfaction based on the questionnaire was assessed. RESULTS: HbA1c level in entire study group decreased after three months, from 9.3 ± 1.0% to 8.8 ± 1.6% (P<0.001). In the group with HbA1c improvement, reduction was the highest: 9.0 ± 1.3% vs. 8.0 ± 1.2% (P<0.001). Only the group with initial HbA1c>10% did not achieve significant improvement: 11.2 ± 0.5% vs. 10.9 ± 1.1 (P=0.06). In satisfaction questionnaire the lowest scores (negative opinion) were reported by group of patients with initial HbA1c above 10%, while the highest scores (positive opinion) were found in the group with improvement of HbA1c after 3 month follow-up. CONCLUSION: Short-term use of CGMS RT, united with satisfaction questionnaire, performed in poorly controlled teenagers with T1DM, can be useful in defining the group of young patients, who can benefit from long-term CGMS RT use in metabolic control improvement.

Cardiovascular risk in nonobese hypertensive adolescents: a study based on plasma biomarkers and ultrasonographic assessment of early atherosclerosis.

The objective of this study was to investigate the vascular status, left-ventricular mass and biomarkers of endothelial activation in hypertensive (HT) adolescents, with particular attention to comparing nonobese with obese patients. Seventy-nine newly diagnosed HT adolescents aged 15.1±2.1 years (divided into 34 nonobese and 45 obese) were compared with 35 healthy volunteers. Intima-media thickness (IMT), flow-mediated dilation (FMD) and left-ventricular mass index (LVMi) were determined using ultrasound. Adhesion molecules and inflammatory interleukins (ILs), together with lipids and insulin resistance (HOMA), were also studied. HT obese adolescents had higher triglycerides, HOMA, and elevated levels of interleukin-6, tumor necrosis factor-α, soluble intercellular adhesion molecule-1 and soluble E-selectin compared with controls and nonobese HT patients. FMD was lower in HT groups (8.5±4.5% in nonobese, P=0.004; 8.1±4.9%, P=0.01 in obese vs 12.5±4.9%; in control), and IMT was higher (0.52±0.06 mm, P<0.001 in nonobese; 0.54±0.05 mm, P<0.001 in obese vs 0.42±0.05 mm in control). Higher LVMi was found in both HT groups, with the highest value in the nonobese group being 37.8±5.3 g m(-2.7) vs 28.4±5.3 g m(-2.7) in controls (P=0.003). In conclusion, nonobese HT adolescents had the same early cardiovascular deteriorations assessed ultrasonographically as their obese HT peers, although metabolic alterations and endothelial activation measured as plasma biomarkers were more pronounced in obese individuals. The potential mechanisms of early atherosclerosis in nonobese HT adolescents need further evaluation in prospective studies because these factors may differ considerably from those found in young obese individuals with HT.

Disturbances in some gene expression in T regulatory cells separated from children with metabolic syndrome.

The metabolic syndrome (MS) is defined as a cluster of risk factors, including abdominal obesity, dyslipidaemia, glucose intolerance and hypertension, which increase the risk for coronary heart disease. The immunological aspects of obesity and MS, including the role of T regulatory cells, have been intensively investigated. The aim of this study was to determine whether there is any disturbance in T regulatory cells number and/or function in children with MS. The percentages of T regulatory cells in the peripheral blood of children fulfilling the International Diabetes Federation criteria of the disease (n = 47) were assessed. Treg cells were also separated for further analysis of multiple genes important in their function with the use of real-time RT-PCR. We did not observe any difference in Treg percentages between study and control group but there was lower expression of some molecules including transforming growth factor-beta and interleukin-12 family members in Treg cells separated from children with MS compared to the healthy subjects. Our study is the first to report significant disturbances in some gene expression in T regulatory cells separated from children with MS. The results should be useful for further research in this field, including immunotherapeutic interventions.

The association of early atherosclerosis and retinopathy in adolescents with type 1 diabetes: preliminary report.

Recent studies have shown a close correlation between advanced diabetic retinopathy and the late stages of atherosclerosis. The purpose of this study was to analyse the association between diabetic retinopathy and early atherosclerotic changes in adolescents with type 1 diabetes. We studied 28 adolescents with type 1 diabetes. Eight patients with nonproliferative retinopathy were compared with the remaining 20 patients, and with 11 healthy controls. The function of endothelium was assessed by measuring flow-mediated dilatation (FMD), the intima-media thickness (IMT) of the common carotid arteries and adhesion molecules (sICAM-1, sVCAM-1, sE-selectin). In the group with retinopathy FMD equalled 7.8+/-4.1% vs. 12.1+/-5.1% in the control group (p=0.04), and in the group without retinopathy, 7.6+/-5.5% (p=0.04 compared to controls). Higher IMT was found in all patients with diabetes in comparison with healthy controls: 0.49+/-0.06 mm vs. 0.42+/-0.03 mm (p=0.001). Patients with retinopathy had a significantly higher value of IMT in comparison not only with controls but also with patients without complications: 0.56+/-0.06 mm vs. 0.47+/-0.03 mm (p=0.0001). Adhesion molecule levels were not changed in patients with retinopathy. Higher IMT was found in adolescents with diabetic retinopathy in comparison with patients without complications, which may suggest that macrovascular changes are more advanced in these patients than in their diabetic peers without retinopathy.