Association between dawn phenomenon and sleep disorders in elderly patients with type 2 diabetes / 中华全科医师杂志

ABSTRACT

Objective To investigate the association between dawn phenomenon and sleep disorders in elderly patients with type 2 diabetes mellitus (T2DM).Methods Three hundred and ninety-six T2DM patients aged 60-80 years were recruited from Department of Endocrinology,Huadong Hospital from January 2014 to January 2017.All cases used oral hypoglycemic drug more than 3 months,their glycosylated hemoglobin (HbA1c) was lower than 8.5％ and underwent continuous glucose monitoring for 72 h.The Pittsburgh sleep quality index (PSQI) scale was applied to evaluate sleep quality,and the PSQI＞7 was defined as the sleep disorder.There was dawn phenomenon in 165 cases (group Ⅰ) and no dawn phenomenon in 231 cases(group Ⅱ).The clinical data,blood glucose related indicators,homeostasis model assessment of insulin resistance (HOMA-IR) and PSQI scores were compared between two groups.The correlation between dawn phenomenon and sleep disorder was analyzed with Logistic regression.Results There were no significant differences in age,BMI,blood lipids,liver and kidney function,hypersensitive CRP(hCRP),serum cystatin and serum cortisol between the two groups (all P＞0.05).Patients in group Ⅰ presented a higher ratio of urinary protein/creatinine [1.3 (0.7,5.4) mg/mmol vs.1.1 (0.5,3.4) mg/mmol,t=-2.105,P=0.04],PSQI scores [(7.3±3.3) vs.(5.4±2.7),t=3.587,P＜0.01] and the incidence of sleep disorders [57.0％ (94/165) vs.25.1％ (58/231),x2=3.765,P＜0.01] than those in group Ⅱ.The HbA1c [(7.4±0.9)％ vs.(7.0±1.0)％,t=3.384,P＜0.01] and fasting glucose [(8.3±1.6) mmol/L vs.(7.0± 1.4) mmol/L,t=8.778,P＜0.01] were significantly higher in group Ⅰ than those in group Ⅱ;while the fasting insulin [(8.2±7.2) mU/L vs.(10.3±10.2) mU/L,t=-2.286,P=0.02] and nocturnal nadir [(5.7± 1.3) mmol/L vs.(6.6± 1.4) mmol/L,t =-6.331,P＜0.01] were lower than those in group Ⅱ.Pearson correlation analysis showed that dawn phenomenon was positively correlated with sleep disorders (r=0.323,P＜0.01).Logistic regression analysis showed that sleep disorders were associated with increased risk of dawn phenomenon (OR=4.143,95％CI1.69-10.16,P＜0.0 1).Conclusion Sleep disorders may play a relevant pathological role in the occurrence of dawn phenomenon in elderly T2DM patients.