Data from: Global assessment of the impact of type 2 diabetes on sleep through specific questionnaires. A case-control study

Type 2 diabetes (T2D) is an independent risk factor for sleep breathing disorders. However, it is unknown whether T2D affects daily somnolence and quality of sleep independently of the impairment of polysomnographic parameters. Material and Methods: A case-control study including 413 patients with T2D and 413 non-diabetic subjects, matched by age, gender, BMI, and waist and neck circumferences. A polysomnography was performed and daytime sleepiness was evaluated using the Epworth Sleepiness Scale (ESS). In addition, 135 subjects with T2D and 45 controls matched by the same previous parameters were also evaluated through the Pittsburgh Sleep Quality Index (PSQI) to calculate sleep quality. Results: Daytime sleepiness was higher in T2D than in control subjects (p=0.003), with 23.9% of subjects presenting an excessive daytime sleepiness (ESS>10). Patients with fasting plasma glucose (FPG ?13.1 mmol/l) were identified as the group with a higher risk associated with an ESS>10 (OR 3.9, 95% CI 1.8-7.9, p=0.0003). A stepwise regression analyses showed that the presence of T2D, baseline glucose levels and gender but not polysomnographic parameters (i.e apnea-hyoapnea index or sleeping time spent with oxigen saturation lower than 90%) independently predicted the ESS score. In addition, subjects with T2D showed higher sleep disturbances [PSQI: 7.0 (1.0-18.0) vs. 4 (0.0-12.0), p<0.001]. Conclusion: The presence of T2D and high levels of FPG are independent risk factors for daytime sleepiness and adversely affect sleep quality. Prospective studies addressed to demonstrate whether glycemia optimization could improve the sleep quality in T2D patients seem warranted.2型糖尿病（Type 2 diabetes, T2D）是睡眠呼吸障碍的独立危险因素。然而目前尚不明确，在多导睡眠图参数异常之外，T2D是否会独立影响日间嗜睡与睡眠质量。材料与方法：本研究为病例对照研究，纳入413例T2D患者与413例非糖尿病受试者，按年龄、性别、体重指数（BMI）、腰围及颈围进行匹配。所有受试者均接受多导睡眠监测（polysomnography），并采用爱泼沃斯嗜睡量表（Epworth Sleepiness Scale, ESS）评估日间嗜睡程度。此外，按上述相同匹配参数纳入135例T2D患者与45例对照受试者，采用匹兹堡睡眠质量指数（Pittsburgh Sleep Quality Index, PSQI）评估睡眠质量。结果：T2D患者的日间嗜睡程度显著高于对照人群（p=0.003），其中23.9%的受试者存在日间过度嗜睡（ESS评分＞10）。空腹血糖（fasting plasma glucose, FPG）≥13.1mmol/L的T2D患者，发生日间过度嗜睡（ESS＞10）的风险更高（优势比[OR]=3.9，95%置信区间[CI]：1.8~7.9，p=0.0003）。逐步回归分析显示，T2D患病状态、基线血糖水平及性别可独立预测ESS评分，而多导睡眠监测参数（如呼吸暂停低通气指数、血氧饱和度＜90%的睡眠时长）则无此预测价值。此外，T2D患者的睡眠障碍程度更高[PSQI评分：7.0（1.0~18.0） vs. 4（0.0~12.0），p＜0.001]。结论：T2D患病状态与空腹血糖升高均为日间嗜睡的独立危险因素，且会对睡眠质量产生不良影响。未来有必要开展前瞻性研究，以明确血糖优化治疗是否可改善T2D患者的睡眠质量。