The Spectrum of Brittle Diabetes

Glycemic variability indices can be used to diagnose islet transplantation success in type 1 diabetic patients

AIMS

High glycemic variability (GV) is the major indication for islet transplantation (IT) in patients with type 1 diabetes (T1D). The actual criteria used to assess graft function do not consider GV improvement. Our study aimed to describe GV indices' evolution in T1D patients who benefited from IT during the TRIMECO trial and to evaluate if thresholds might be defined to diagnose IT success.

METHODS

We collected data from 29 patients of the TRIMECO trial, a clinical trial (NCT01148680) comparing the metabolic efficacy of IT with intensive insulin therapy. Based on CGM data, we analyzed mean glucose level and four GV indices (standard deviation, coefficient of variation, MAGE and GVP) before (M0) and 6 months (M6) after IT.

RESULTS

Each GV index decreased significantly between M0 and M6: SD 53.9 mg/dL [44.6-61.5] versus 20.1 mg/dL [13.5-24.3]; CV 35.2% [30.6-37.7] versus 17.3% [12.0-20.5]; MAGE 134.9 mg/dl [111.2-155.8] versus 51.9 mg/dL [32.4-62.4]; GVP 35.3% [24.9-47.2] versus 12.2% [6.2-18.8] (p ≤ 0.0001). Thresholds diagnosing IT success at 6 months post-transplant were an SD at 22.76 mg/dL (sensibility 88.89%, specificity 80.00%), a CV at 17.47% (sensibility 88.89%, specificity 70.00%), a MAGE at 54.81 mg/dL (sensibility 88.89%, specificity 80.00%) and a GVP at 12.27% (sensibility 88.89%, specificity 70.00%).

CONCLUSIONS

This study confirms a positive impact of IT on GV. The proposed thresholds allow an easy evaluation of IT success using only CGM data and may be a clinical tool for the follow-up of transplanted patients.

Alexithymia in adults with brittle type 1 diabetes

BACKGROUND

The term "brittle" is used to describe an uncommon subgroup of patients with type 1 diabetes whose lives are disrupted by severe glycaemic instability with repeated and prolonged hospitalization. Psychosocial problems and emotional disturbances are the major perceived underlying causes of brittle diabetes. Aim of this study is (a) to assess alexithymia in patients with brittle and non-brittle diabetes, and (2) to examine its relationship with specific parameters of general psychopathology.

METHODS

Participants comprised 44 patients with brittle diabetes and a case-control group of 88 individuals with stable (non-brittle) diabetes, matched for age, gender, years of education, and diabetes duration. Alexithymia and general psychopathology were assessed using the "20-item Toronto Alexithymia Scale" (TAS-20) and the "Symptom Checklist-90-Revised" (SCL-90-R).

RESULTS

Patients with brittle diabetes were more alexithymic than the control group. Alexithymia scores showed significant correlations with SCL-90-R anxiety and somatization subscales, but were relatively independent from gender, education, diabetes duration and complications, depression and glycaemic control.

CONCLUSIONS

Given the impact of alexithymia on type 1 diabetes, the early detection and intervention of alexithymic subjects are very important for a better outcome of diabetes.