Endocrine Abstracts

Purpose: Previous studies have established that obstructive sleep apnea (OSA) frequently co-exists in persons with type 2 diabetes (T2DM) with negative effects on glycemic control and functional outcomes. However, there is limited data about the effect of insomnia or co-morbid OSA and insomnia among those with T2DM. We compared glucose control, functional outcomes, sleep quality, and daytime sleepiness among 4 groups of participants with T2DM: (i) OSA, (ii) insomnia, (iii) OSA+insomnia, and (iv) normal sleep.

Methods: This study was a secondary analysis of baseline data from the Diabetes Sleep Treatment Trial (R01-DK096028). Measures evaluated OSA severity (ApneaLink Plus to determine apnea + hypopnea index [AHI]; AHI≥10=OSA), insomnia severity (Insomnia Severity Index [ISI]; scores≥15=clinical/moderate insomnia), sleep quality (Pittsburgh Sleep Quality Index [PSQI]; global scores5=poor sleep quality); functional outcomes (Functional Outcomes of Seep Questionnaire [FOSQ]; normal≥18), and excessive daytime sleepiness (Epworth Sleepiness Scale [ESS]; ESS≥10=excessive sleepiness). Clinical evaluations with A1C and height /weight measurements for body mass index (BMI kg/m²) were obtained. Descriptive statistics and apriori planned comparisons of (insomnia, insomnia+OSA) versus (Normal, OSA) were conducted on the targeted outcomes with statistical significance set at P.05.

Results: The sample (n=168, 46% male, mean age=56±10.4 years, mean A1C=8.0±1.9%, mean BMI=35±6.8) was subjectively sleepy (mean ESS=9.8±4.7) with poor sleep quality (mean PSQ1=10.2±4.2) and decreased functional outcomes (mean FOSQ=16.5±2.9). Only 31% (n=53) had “normal” sleep; 23% (n=38) had insomnia; 27% (n=45) had OSA (AHI≥10); and 19% (n=32) had co-existing OSA and insomnia (AHI≥10+ ISI≥15). Participants with either insomnia or co-existing OSA and insomnia had significantly (P.05) higher A1C scores, worse functional outcomes, sleep quality, and daytime sleepiness compared to participants with only OSA or normal sleep.

Conclusions: Insomnia is highly prevalent in persons with T2DM and is associated with impaired glycemic control, poor sleep quality, daytime sleepiness and lower functional outcomes that worsen when insomnia co-exists with OSA.