Endocrine Abstracts

Introduction: Sleep restriction and/or impaired sleep quality negatively influence glucoregulation. The aim of this study was to assess subjective sleep parameters in patients with type 1 diabetes, to relate sleep parameters to long-term glycaemic control, and to assess possible risk factors for impaired sleep.

Research design and methods: We studied 99 adult patients with type 1 diabetes (55M, 44F, duration of diabetes 26.9±1.2 years) and 99 age-, gender-, and BMI- matched non-diabetic controls. Subjective sleep characteristics were assessed by validated questionnaires, i.e. Pittsburgh Sleep Quality Index (PQ4I), Epworth Sleepiness Scale (ESS), and the Berlin Questionnaire (BQ). Glucoregulation was assessed by HbA1c-values. Clinical parameters were obtained from medical charts. Depression was assessed by the Hospital Anxiety and Depression Scale (HADS). Peripheral polyneuropathy was assessed by neurological examination and quantitative sensory testing.

Results: Thirty-five percent of the patients with type 1 diabetes had subjective poor sleep quality compared to 20% of the control subjects (P=0.021). A higher proportion of the patients with type 1 diabetes were at increased risk for obstructive sleep apnoea (OSA) (17.2 vs 5.1%, P=0.012). There was no significant association between individual sleep characteristics and HbA1c-values. On logistic regression analysis, HADS depression score, presence of polyneuropathy, habitual snoring, and other sleep disturbances, i.e. hypoglycaemia, were independently associated with poor sleep quality.

Conclusion: Adult patients with longstanding type 1 diabetes have disturbed subjective sleep quality and a higher risk for OSA, compared to control subjects. Subjective sleep disturbances are part of the complex syndrome of longstanding type 1 diabetes.