Association of Sleep, Body Weight and Physical Exercise with Plasma BDNF Levels in Healthy Male Saudi Smokers.

Introduction: Brain-derived neurotrophic factor (BDNF) has been shown to impact neural function and development. The BDNF plasma levels may be affected by a smoker's behavior. Thus, the aim of this study was to investigate the association between sleep, body weight and physical exercise with brain-derived neurotrophic factor (BDNF) in healthy male Saudi smokers. Methods: A cross-sectional study, with a convenience sample, was conducted during personal visits to the Anti-Smoking Clinic and Family and Community Medical Center of Imam Abdurrahman Bin Faisal University (IAU) in Dammam at the end of 2018. Blood samples were taken from participants to measure the BDNF plasma levels. Multiple linear regression analysis was used to examine the relationship between plasma BDNF levels and participants' background characteristics, such as smoking index, physical activity, body mass index (BMI) and Pittsburgh sleep quality index (PSQI). Results: A sample of 73 (31 smokers and 42 non-smokers) males took part in the study. The results demonstrated a significant relationship between plasma BDNF levels with physical activity, smoking age, smoking index, PSQI and BMI 25-29.9 (overweight). However, the results showed no significant relationship between plasma BDNF levels and BMI (healthy weight) and obesity. Conclusion: This study shows that physical activity and sleeping quality can provide a positive impact against smoking-associated variation of the BDNF plasma levels, which may affect the health of Saudi males. Further investigation is needed to understand what other potential background characteristics are best predictive or correlated with BDNF plasma levels.