Background: Sleep disorders are frequently reported in patients with type 2 diabetes. However, there are few reports on the prevalence and correlates of sleep disorders in diabetics. This study investigated the prevalence and factors associated with sleep disorders in type 2 diabetics.

Research Design and Methods: In total, 544 patients with type 2 diabetes mellitus (311 males, 233 females; age 63.9 ± 12.6-years-old; HbA1c, 7.1 ± 0.9%) and 1,161 control subjects (38.1% males; 54.5 ± 15.4-years-old; HbA1c 5.8 ± 0.6%) were included. Participants used self-administered questionnaires on sleep attitude (Pittsburgh Sleep Quality Index; PSQI), quality of life (the Short Form 36 Health Survey; SF-36), depression (the Center for Epidemiologic Studies-Depression scale), and personality (Ten Item Personality Inventory). The socio-demographics, laboratory data, and medical history were collected from medical records.

Results: The number of subjects with sleep disorders (PSQI > 5) was higher in diabetic patients (25.9%) than control subjects (20.6%) (p = 0.02), although sleeping time was significantly longer in diabetic (7.42 hours) than in control subjects (7.09 hours) (p < 0.01). Among diabetic patients, the sleep disorders group showed higher percentages of females (p < 0.01), spouseless subjects (p < 0.01), insulin users (p < 0.01), depression (p < 0.01), overactive bladder (p = 0.01), and benign prostatic hyperplasia (p < 0.01). Diabetic patients with sleep disorders scored higher on the neuroticism scale than patients without sleep disorders (p < 0.01). All SF-36 scores were lower in patients with sleep disorders. No differences were found in age, body mass index, 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. Otaka: None. H. Murakami: None. S. Mizushiri: None. A. Kamba: None. M. Daimon: None.

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