ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Endocrine Abstracts (2019) 63 P919 | DOI: 10.1530/endoabs.63.P919

Diabetes Eruditus: Characteristics of type 1 diabetes of long duration

Diana Borges Duarte, Cláudia Amaral, Ana Amado, Sofia Teixeira, André Carvalho, Joana Vilaverde, Cláudia Freitas, Isabel Palma, Jorge Dores, Rui Carvalho, Conceição Bacelar, Helena Ramos & Helena Cardoso


Department of Endocrinology - Centro Hospitalar e Universitário do Porto, Porto, Portugal.


Introduction and aim: Type 1 diabetes mellitus (T1DM) presents as a challenge for both health care providers and patients looking to avoid chronic complications and early mortality. Clinical features of patients with long duration T1DM are still poorly studied and debated. The aim of our work was to describe the clinical features of subjects with long duration T1DM.

Methods: Cross-sectional study of patients with T1DM with more than 40 years of evolution followed at our Endocrinology outpatient clinic. Clinical (age and symptoms at diagnosis, insulin dose and regimen, diabetes complications and other medical illnesses), laboratory (HbA1c of the last 6 months, lipid profile, urinary albumin/creatinine ratio [UACR]) and anthropometric data were collected. We excluded patients submitted to pancreatic transplantation with a functioning graft and those lost from regular follow-up.

Results: Forty-seven patients (53.2% male) were included. Their mean age was 60.6±9.3 years with a median age-at-onset of diabetes of 12.5 (1.1–40) years. The median body mass index at last evaluation was 24.1 (19.1–39.5)kg/m2.Classical diabetes symptoms were found at diagnosis in 85.1% (n=40) of the individuals; clustering of other autoimmune diseases was identified in 31.9% (n=15), exclusively thyroid dysfunction. Concerning current treatment, 53.2% (n=25) were on a multiple daily injections regime, 29.8% were on a functional insulin therapy (half of them with continuous subcutaneous insulin infusion); with a median total daily insulin dose of 0.48 (0.28–1.08) units/kg. Flash-glucose monitoring was used by 63.8%(n=30) of the individuals. Last mean HbA1c was 8.0±1.3%; median of total, LDL and HDL cholesterol, and triglycerides was 148.0 (95–381), 77.0 (38–267), 54.5 (33–101) and 78.5(39–352) mg/dl, respectively. Last mean glomerular filtration rate (MDRD formula) was 73.3±26.5 ml/kg per 1.73 m2; 46 patients had UACR available, of those, 58.7%(n=27) had a normal UACR(<30 mg/g), 26.1%(n=12) moderately increased (30–300 mg/g) UACR and 14.9%(n=7) had albuminuria(UACR > 300 mg/g). None of the patients had end stage renal disease.Concerning to other diabetes complications, 93.6%(n=44) of the individuals had at least one; diabetic retinopathywas present in 91.5%(n=43), followed by neuropathy (distal sensorimotor or autonomic) in 46.8%(n=22); and nephropathy in 41.3%(n=19).

Conclusion: Our group of patients with long duration T1DM, despite out-of-target HbA1c levels, are fairly protected from diabetic nephropathy. Their clinical features, with a relatively low total daily insulin dose and singular lipid profile with relatively high HDL-cholesterol and low triglycerides levels, may represent a long survival feature. This study should prompt the analysis of early prognosis markers in T1DM.