Brain-Derived Neurotrophic Factor is Associated with Self-Reported Quality of Sleep in Type 2 Diabetes Patients in Ghana.

Objective: Sleep disturbances are common in patients with type 2 diabetes (T2DM), and this exacerbates disease severity and results in poor quality of life. Brain-derived neurotrophic factor (BDNF) has been reported to mediate the association between T2DM and poor sleep health. The burden of self-reported poor sleep quality and duration in T2DM and their association with serum BDNF levels were investigated.

Methods: In this case-control design, the Pittsburgh Sleep Quality Instrument was used to assess self-reported sleep quality and duration in 100 patients with T2DM and 80 nondiabetic controls. Sociodemographic data and medical history were collected from case notes and/or using a structured questionnaire. Fasting venous blood samples (5 mL) were collected to measure plasma lipid profile and serum BDNF levels.

Results: patients with T2DM had low levels of BDNF, poor sleep quality (61.9% vs 27.5%, p<0.001), and shorter sleep duration (6.1±2.2 vs 6.9±1.1 h, p=0.003). T2DM status was associated with doubling the odds of poor sleep quality [OR (95%CI)=2.06 (1.07-6.43), p=0.039] and 1.6 times the odds of short sleep duration [1.63 (1.03-3.79), p=0.028]. Multivariable logistic regression analysis revealed no association between serum BDNF levels and sleep status. However, there was a negative biological interaction between T2DM and BDNF levels on poor sleep quality, resulting in 0.28 relative excess risk due to the interaction and a 12% attributable proportion due to the interaction.

Conclusion: In this study population, patients with T2DM had a high burden of self-reported poor quality of sleep and shorter sleep duration compared to the nondiabetic controls. T2DM interacts negatively with serum BDNF levels to affect sleep quality.