Table 4.

Studies on the etiopathogenesis of the comorbidity between AN and depressive disorder

Study	Sample	Diagnostic criteria/evaluation	Results of eating behaviour disorder
Boehm et al., 2018 [24]	130 subjects (35 with severe AN, 33 recovered from AN, 62 C)	Self-reports in which depressive and anhedonia symptoms were collected	No direct relationship between BMI and depression in AN. Anhedonia in AN is not related to depression
Thornton et al., 2016 [21]	6,899 women from the Swedish study in twin adults	SCID-I	Shared genetic factors were observed for AN, depression and suicide risk
Lawson et al., 2013 [25]	35 women (13 with AN, 9 recovered from AN and 13 C)	STAI, BDI-II/DSM-IV-TR	Abnormal postprandial secretion of oxytocin is associated with anxiety and depression in AN
Mattar et al., 2012 [22]	24 women with AN	BMI, Y-BOCS/DSM-IV	Anxiety symptoms and depression improve with nutritional rehabilitation in AN. However, they are not directly related to the BMI
Mattar et al., 2011 [23]	Revision of 7 studies on AN, depression, anxiety and malnutrition	BMI, Y-BOCS/DSM-IV	Contradictory results were observed in the relationship between malnutrition, and anxiety and depression in AN
Lawson et al., 2009 [26]	52 women (21 C, 13 with hypothalamic amenorrhea and 18 with AN and amenorrhea)	HRSA/HRSD	Higher levels of cortisol were found in patients with AN. Higher levels of cortisol were positively associated with depression and anxiety
Miller et al., 2007 [27]	43 subjects with AN	HRSA/HRSD	Lower testosterone levels were associated with anxiety and depression in AN
Wade et al., 2000 [20]	2,163 twin women (including 1,030 twin partners)	DSM-III-R structured clinical interview for anorectic and depressive symptoms	AN has a heritability of 58%. Genetic factors would be involved in the comorbidity between AN and depression
Berk et al., 1997 [29]	12 patients with AN, 11 patients with BN and 17 C	HRSD	Patients with AN and depressive comorbidity, have an increased response to intracellular calcium, which is related to depression
Schweitzer et al., 1990 [28]	20 subjects with AN	Dexamethasone suppression test	50% of the sample obtained an abnormal response in the dexamethasone suppression test. No relationship was found with weight. Higher scores in depression where found in those with an abnormal response

AN, anorexia nervosa; BN, bulimia nervosa; BDI, Beck Depression Inventory; BMI, body mass index; C, controls; HRSA, Hamilton Rating Scales for Anxiety; HRSD, Hamilton Rating Scales for Depression; SCID-I, Structured Clinical Interviews for DSM-IV; STAI, State-Trait Anxiety Inventory; Y-BOCS, Yale-Brown Obsessive Compulsive Scale; DSM-IV-TR, Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision; DSM-IV, Diagnostic and Statistical Manual of Mental Disorders, 4th Edition; DSM-III-R, Diagnostic and Statistical Manual of Mental Disorders, 3rd Edition, Revised