Mental health, sleep and diet: a cross-sectional association of empirically dietary inflammatory index with depression, anxiety, stress and sleep quality in breast cancer survivors

Purpose High inflammation and side effects of cancer treatments may make survivors liable to some disorders, like poor sleep quality and mental disorders. Along with pharmacological and nonpharmacological therapies, a healthy dietary intake may have therapeutic effects by changing the inflammation status. So, this study aims to derive a cross-sectional association of an empirical dietary inflammatory index with depression, anxiety, stress and sleep quality in breast cancer survivors (BCSs). Design/methodology/approach In total, 223 BCSs were invited to the main centers of cancer diagnosis and treatment [Seyyed Al-Shohada Hospital and the Iranian Cancer Control Charity Institute (MACSA)]. Sleep quality and mental status (depression, anxiety and stress) of participants were assessed by validated questionnaires. The Empirical Dietary Inflammatory Index (EDII) was calculated in two anti- or pro-inflammatory groups. Using linear and logistic regression, the association between EDII, sleep and the mental status of BCSs was assessed. Findings More than 50% of participants have reported impaired sleep quality or mental status. Results of linear and logistic regression did not show any significant relationship between total EDII and these variables. However, supplementary linear regression showed a potentially positive relationship between increased consumption of some pro-inflammatory items of EDII score and worsening scores of study outcomes. Moreover, a potentially inverse linear relationship between anti-inflammatory food items and better sleep and mental status was observed. Originality/value Findings of this study showed that having more anti-inflammatory food items might be associated with better sleep quality and mental status. More research will be required to find out the association between EDII and the higher risk of these abnormalities.