Background: Sleep disorders are associated with type 2 diabetes, and result in a low quality of life. However, there are few reports on the prevalence and correlates of sleep disorders in diabetics. This study investigated the prevalence and factors, including personality traits, associated with sleep disorders in type 2 diabetics.

Research Design and Methods: A case-control study was performed in patients with type 2 diabetes mellitus (223 males, 208 females; age 60.8 ± 12.8-years-old; HbA1c, 7.2 ± 0.9%) compared with age-/sex-matched healthy controls (219 males, 217 females; age 60.8 ± 13.0-years-old; HbA1c, 5.6 ± 0.3%). Participants used self-administered questionnaires on sleep attitude (Pittsburgh Sleep Quality Index; PSQI), quality of life (SF-36), depression (CES-D), and personality (Ten Item Personality Inventory).

Results: The number of subjects with sleep disorders (PSQI > 5) was higher in diabetic patients (26.9%) than control subjects (17.4%) (p < 0.01). Sleep latency was longer in diabetic patients (20.2 ± 0.8 minutes) than control subjects (13.7 ± 0.5 minutes) (p < 0.01). Among diabetic patients, patients with sleep disorders were significantly younger (p = 0.04) and showed higher body mass index (p=0.04), higher percentages of females (p = 0.03), depression (p < 0.01), overactive bladder (p = 0.01), and benign prostatic hyperplasia (p < 0.01). Diabetic patients with sleep disorders scored higher neuroticism (p < 0.01), lower agreeableness (p = 0.01) and lower conscientiousness (p < 0.01) scale than patients without sleep disorders. All SF-36 scores were lower in patients with sleep disorders. No differences were found in HbA1c, stage of diabetic retinopathy and nephropathy between patients with the presence or absence of sleep disorders.

Conclusions: The prevalence of sleep disorders was high in patients with type 2 diabetes, and their quality of life was impaired. Therefore, clinicians should monitor sleep disorders among these patients.


H. Murakami: None. M. Daimon: None. S. Mizushiri: None.


Japan Society for the Promotion of Research

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