Sleep Problems

Review by Anne Marie O'Melia

Asaad Abdou, T., Esawy, H. I., Abdel Razek Mohamed, G., Hussein Ahmed, H., Elhabiby, M. M., Khalil, S. A., & El-Hawary, Y. A. (2018). Sleep profile in anorexia and bulimia nervosa female patients. Sleep Medicine, 48, 113-116.

Complaints of sleep problems are common in patients with eating disorders. Sleep and food serve as our primary sources of energy. Not surprisingly, sleep and eating patterns have been shown to be closely associated. A deficit in one type of energy source affects the other. Deficits in nutrition have wide ranging impacts on physiologic and psychologic functioning. Sleep deprivation and irregularities similarly impact our cognition, mood, anxiety, hormone balances and, importantly, our hunger and fullness cues. A 2010 study by Kim and colleagues (Psychiatry Res. 2010 Mar 30;176(1):88-90.) showed that approximately half of female patients suffering from anorexia nervosa (AN) or bulimia nervosa (BN) self reported sleep problems, especially problems falling asleep (early insomnia) and problems with frequent wakening during the night (middle insomnia).

A recent study by Abdou et al. sought to better understand sleep patterns in AN and BN female patients using both self-reporting and objective assessment measures. This was a cross sectional study using the Sleep Disorder Questionnaire and full night polysomnography (PSG) in 23 female patients with AN and BN. Depression is also know to affect sleep and this study also assessed depressive symptoms in the patients and control group. Patients were 18–45 year of age and were not receiving any treatment for sleep. Study participants were compared to a sex and age matched control group (20 participants).

All types of insomnia were self-reported at higher incidence in the eating disorder patients compared to controls including early, middle and late (early morning awakening) insomnia. Patients also frequently described several parasomnias including nightmares, sleep related panic and bruxism (teeth grinding and jaw clenching). Similar to the earlier study by Kim et al, both AN and BN patients reported early insomnia was described most commonly (56.5%) followed by middle insomnia (47.8%). Additionally, 21.7% of the eating disorder patients complained of late insomnia and 39% reported parasomnias.

Objective information about sleep gathered via PSG also showed significant differences in AN and BN patient’s sleep architecture compared to controls. The eating disorder patients took longer to fall asleep, had reduced sleep efficiency and a significant increase in their arousal index.

Depression is known to affect sleep complaints and sleep architecture but the PSG data suggests that the AN and BN patients’ sleep problems cannot be explained by their depressive symptoms alone. Elevated depression scores using the Beck Depression Inventory II were correlated to many changes in length and quality of several stages of sleep in patients with AN and were correlated only with a change in Stage 1 sleep in BN patients.

This study observed that sleep problems are common in both BN and AN patients, confirming that sleep and eating disorders are highly correlated. Thus, sleep may be a useful clinical marker in eating disorders. As we continue to understand this connection between sleep issues and eating disorders, we can also become more attentive to developing preventative measures and intervention techniques, both pharmacologic and nonpharmacologic in treatment settings.