Night Eating Syndrome Among Euthymic Patients With Bipolar I  Disorder May Be Common and Related With Eating Concerns and Atypical Depression: A Cross-Sectional, Clinic-Based Study

 Sema Ulukayaa, Ozge Sahmelikoglu Onur b*, Murat Erkiran c

a Bakirkoy Research and Training Hospital for Psychiatry Neurology and Neurosurgery, 4th Department of Psychiatry, Istanbul, Turkey; b Bakirkoy Research and Training Hospital for Psychiatry Neurology and Neurosurgery, 3rd Department of Psychiatry, Istanbul, Turkey; c Bakirkoy Research and Training Hospital for Psychiatry Neurology and Neurosurgery, 9th Department of Psychiatry, Istanbul, Turkey.

  

 

Abstract

Background: Current studies indicate a strong relationship between Night Eating Syndrome (NES) and obesity, while studies on Bipolar Disorder (BPD) show that patients with BPD form an important risk group in terms of obesity.  The aims of this study were to investigate the frequency of NES in patients with (Bipolar Disorder Type  1) BPD1; and to determine the clinical features associated with NES.

Methods: A total of 94 euthymic patients diagnosed with BPD1 according to Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM 5) were evaluated with Sociodemographic Data Form, Structured Clinical Interview for DSM-IV (SCID-I), Young Mania Rating Scale (YMRS), Hamilton Depression Scale (HDS), Beck Anxiety Inventory, Eating Disorder Examination Questionnaire (EDE-Q), Night Eating Questionnaire (NEQ), Night Eating Syndrome Questionnaire (NESQ). The diagnosis of NES was made by clinical interview with the participants for the differential diagnosis of other eating disorders and sleep disorders. The height, weight, and waist circumference of the participants were measured. The results of all analyses were considered significant when p <0.05

Results: The incidence of NES in BPD1 was 34%. The presence of AD, atypical antipsychotic medication use, binge eating, eating concern and HDS scores were significantly higher in BPD1 patients with NES than BPD1 patients without NES (p<0.05) The presence of AD, the use of atypical antipsychotics and eating concern were found to be significant determinants of NES in BPD1 (p<0.05).

Conclusions: Our results may have implications for the choice of treatment and course of BPD1.  Studies comparing normal controls and BPD1 are viewed as very promising for the conceptualization of BPD1.

Keywords: bipolar disorder, night eating syndrome, eating disorder, obesity.

 

       

Introduction

The diagnostic criteria of  Night Eating Syndrome (NES) involve an abnormally increased food intake in the evening and nighttime, manifested by (1) consumption of at least 25% of intake after the evening meal, and/or (2) nocturnal awakenings with ingestions at least twice per week. Awareness of the eating episodes is required, as is distress or impairment in functioning. Besides, three of the five following criteria are required: (1) morning anorexia, (2) a strong desire or urge to eat between dinner and sleep initiation and/or upon awakening at night from sleep, (3) sleep onset and maintenance insomnia, (4) the belief that one must eat in order to get to sleep, and (5) depressed mood or lowering of mood in the evening and nighttime [1]. The American Psychiatric Association defined NES under the ‘other specified feeding or eating disorder’ title in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) [2]. Although ultimately included into DSM-5, Shoar et al. suggested that  NES is still unknown by many health-care providers and current diagnostic criteria do not seem to change the practice in a clinical setting [3].

 

This syndrome may be associated with depressive mood and low self-esteem in affected individuals [4,5]. Increases in depressive mood, especially in the evening or at night, have been reported  in patients with NES, and depressive mood in individuals with NES may be associated with a typical lack of control over eating at night [6,1].  In patients with bipolar disorder (BPD), the investigation of eating disorders as a comorbidity has been relatively less of a research focus when compared to the lifelong comorbidities of other psychiatric disorders [7]. However, Mc Elroy et al. found that the evaluation of comorbid eating disorders in BPD may be important for the treatment of both diseases [8].

Current studies indicate a strong relationship between NES and obesity [9] while studies on BPD show that patients with BPD form an important risk group in terms of obesity and metabolic syndrome [10]. Therefore, evaluation of the association of NES in patients with BPD may be important. A review of the literature indicates that NES comorbidity in patients with bipolar disorder type 1 (BPD1) has not yet been investigated and the number of comorbidities in patients with BPD studies was relatively small [11]. BPD1 is a bipolar spectrum disorder characterized by the occurrence of at least one manic episode, with or without depressive episodes [12]. The first aim of this study was to investigate the frequency of NES in patients with BPD1, and the second objective was to determine the clinical features associated with NES.

Methods

The study sample consisted of patients who presented at the Outpatient Follow-up and Treatment Unit of Bakırköy Psychiatric and Neurological Diseases Training and Research Hospital between July 2016 and June 2017.On 06.09.2016, the ethics committee approval numbered 577 was obtained from our hospital. Written informed consent was obtained from the patients who participated in the study.

 

A total of 94 patients diagnosed with BPD1 according to DSM-5 were included in the study. The psychiatric diagnoses of the participants were evaluated using the Structured Clinical Interview Scale (SCID-I) for DSM-IV Axis I disorders. Patients with another comorbid psychiatric disorder; sleep-related eating disorders according to the International Classification of Sleep Disorders; psychiatric disorders due to mental retardation or neurological or internal diseases; history of head trauma; history of psychosurgery or other brain surgery interventions; history of alcohol and/or substance abuse or addiction during the study period; fasting during the study period; or dieting to gain or lose weight; as well as patients who would be awake at night because of working shifts, were not included in the study (Figure 1). The diagnosis of NES was made by clinical interview with the participants for the differential diagnosis of anorexia nervosa, bulimia nervosa, binge eating disorder, and sleep-related eating disorder, and the diagnosis of NES was made according to the criteria recommended by Allison et al. [1]. The height, weight, and waist circumference of the participants were measured after the interview. Height measurements were made without shoes. The waist circumference was measured from the anterior superior level of the right iliac in the horizontal plane when the patient was naked and at the end of an expiration. The body mass index (BMI) was obtained by dividing the weight measured in kilograms by the square of the height measured in meters. Participants whose BMI was below 18.5 kg/m² were considered underweight, participants whose BMI ranged from 18.5–25 kg/m² were considered normal weight, 25–30 kg/m² were considered overweight, 30–35 kg/m² were considered Grade 1 obese, 35–40 kg/m² were considered Grade 2 obese, and participants whose BMI was 40 kg/m² and above were considered Grade 3 obese.

 

 

Sociodemographic Data Form:

It is a form prepared by the researchers in order to determine the suitability of the participants to the inclusion and exclusion criteria and to determine their sociodemographic characteristics. The form includes general information about the participants’ age, gender, marital status, education, occupational characteristics, as well as questions about their personal history and family history. In the form, clinical data such as age of onset of disease, number of attacks, types of attacks, number of hospitalizations and suicide attempt history were also included.

 

Structured Clinical Interview for DSM-IV (SCID)

This is a diagnostic tool used to determine DSM-IV Axis I disorders, as assessed by a professional interviewer. Consisting of six modules, the instrument was developed by First et al. [13]. The validity and reliability of the Turkish version has been confirmed by Ozkurkcugil, under the name of Structural Clinical Interview for DSM-IV Axis-I Disorders [14].

 

Young Mania Rating Scale (YMRS)

The YMRS was developed by Young et al. and consists of 11 items, each measuring the severity of a symptom on a scale of 0–4 [15]. Validity and reliability studies for the Turkish version of the scale were conducted by Karadag et al. [16].

 

Hamilton Depression Rating Scale

This scale consists of structured questions and each question is scored from 0–4. The scale was developed by Hamilton and Williams in 1978 and was adapted to Turkish by Akdemir et al. [17,18]. In this study, it was applied to control for the depression variable.

 

Beck Anxiety Inventory:

The aim of the scale is to measure the frequency of anxiety symptoms experienced by the individual. It was developed by Beck et al. and the reliability and validity study in our country was developed by Ulusoy et al. [19,20].

 

Eating Disorder Examination Questionnaire (EDE-Q):

The EDE-Q is a 28-item self-assessed questionnaire version of the Eating Disorder Examination Interview, a semi-structured interview that is considered as the ‘gold standard’ in the evaluation of eating disorders [21]. The Turkish translation of the scale was studied in adolescents and was found to be valid and reliable [22].

 

Night Eating Questionnaire:

For the psychiatric outpatient population, the “Night Eating Questionnaire (NEQ)” was developed as a screening questionnaire for the diagnosis of NES, and its validity and reliability was demonstrated [23]. NEQ is a screening questionnaire consisting of 14 questions that was developed by Allison et al. [1].

Night Eating Syndrome Questionnaire:

         In this questionnaire which is applied to individuals diagnosed with NES, the time of onset of NES, whether the individiual applied for treatment, the relationship of NES with psychiatric diseases and the drugs used for this reason, the evening or night eating times, the presence of periodic findings in night meals, the relationship of vital stressors with NES and the presence of the same complaints in close relatives was questioned. This questionnaire was previously used in a study investigating Night Eating Syndrome in Anxiety Disorders [24].

Statistical Analysis

SPSS 24 for Mac was used for statistical analysis in order to evaluate the findings. Descriptive statistical methods (mean, standard deviation, frequency) were used to evaluate the study data. For the comparison of qualitative data, Chi-square test was used and Yates’s correction was used if the expected frequencies were not met. Student’s t-test was used for comparisons of variables when parametric assumptions were met, and Mann Whitney U test was used for comparisons of variables when parametric assumptions were not met. Univariate and multivariate logistic regression analysis was used to predict NES in BPD1 patients. The results of all analyses were considered significant when p <0.05 and p <0.01.

Results

Sociodemographic characteristics, BMI, weight and waist circumference were compared between patients with and without NES in the BPD1 group. There was no statistically significant difference between the groups in terms of variables (p>0.05) (Table 1).

 

Data on general medical characteristics, smoking, alcohol and substance use variables of BPD1 patients with NES (NES (+) BPD1) and BPD1 patients without NES (NES (-) BPD1) groups were compared. There was no statistically significant difference between the groups (p> 0.05) (Table 2).

 

Data on the clinical characteristics of the NES (+) BPD1 and NES (-) BPD1 groups were compared. There was a statistically significant difference between the groups in terms of atypical antipsychotic use variable (p <0.05). The ratio of atypical antipsychotic use in the NES + BPD group was significantly higher than the NES (-) BPD1 group (p <0.05). There was a statistically significant difference between the BPD1 group with NES and without NES in terms of AD and chronic progression variables (p <0.05). The ratio of AD in the NES (+) BPD1 group was higher than the NES (-) BPD1 group. In terms of the chronic progression variable; the ratio of chronic progression in the NES (-) BPD1 group was higher than the NES (+) BPD1 group (Table 3).

The HAM-D, Beck Anxiety and YMRS data of NES (+) BPD1 and NES (-) BPD1 groups were compared. There was a statistically significant difference between the groups in terms of HAM-D scores (p <0.05). The HAM-D scores of the NES (+) BPD1 group were significantly higher than the NES (-) BPD1 group. There was no statistically significant difference in Beck Anxiety and YMRS scores (p> 0.05) (Table 4 ).

There was a statistically significant difference between the NES (+) BPD1 and NES (-) BPD1 groups in terms of all subscales and total scores of NEQ (p <0.01). The scores of the NES (+) BPD1 group were higher than the NES (-) BPD1 group. There was a statistically significant difference between the groups in terms of binge eating (p <0.05), eating concern (p <0.01), and total (p <0.05) scores of EDE-Q between the NES (+) BPD1 and NES (-) BPD1 groups. In terms of these variables, the scores of the NES (+) BPD1 group were significantly higher than the NES (-) BPD1 group (Table 5).

 

Logistic regression analysis was used to investigate the multivariate risk factors for significant variables between BPD1 patients with and without NES. Risk status (odds ratio) was calculated with reference to working status, chronic progression, atypical depressive episode, regular atypical antipsychotic use, HAM-D, NEQ total score, EDE-Q binge eating, eating concern variable scores. Forward multiple logistic regression analysis was performed to evaluate the predictive properties of NES in patients with BPD1. When other variables remain constant, the use of atypical antipsychotics increases 4.04 times, the presence of atypical depression history increases 0.28 times, and one unit increase of the EDE-Q eating concern variable increases 0.42 times (Table 6).

Discussion

The present investigation focused on the frequency and clinical features of NES in patients with BPD1. The incidence of NES in patients included in the study was 34%. The presence of atypical depression, atypical antipsychotic medication use, binge eating, eating concern, and Hamilton depression scores were significantly higher in patients with NES. The presence of atypical depression, the use of atypical antipsychotics, and eating concern were also significant determinants of NES when regression analysis was applied to identify the NES determinants in the patients included in the study.

Cengiz et al. found a frequency of NES of 19.8% in 383 outpatients [25]. whereas Saraçlı et al. found a frequency of NES of 22.4% in their study conducted with 433 psychiatric outpatients [26]. A frequency of NES of 8% was found in patients with BPD [11].  In our study, the frequency of NES was 34%, and this is a relatively high ratio. The difference between the studies may reflect cultural, differences in disease severity and the use of different criteria in different samples. There is a report in the literature suggesting (Night Eating Diagnostic Questionnaire ) NEDQ may be a cohesive assessment of NES [27]. Further studies with NEDQ may be needed to examine the frequency of NES.

A study conducted with university students showed that depressive symptoms may be one of the predictors of NES [28]. Küçükgöncü et al. found a frequency of NES of 15.7% in patients with major depression and anxiety disorders and noted that NES was significantly more frequent in depressive patients [24]. NES scores were found to be significantly and positively associated with psychological distress in a study by He et al. [29]. Also emotional eating and NES are  found to be in association with nutrient intakes and sleep quality in adolescents [30]. We also found that the Hamilton Depression scores were higher in NES (+) BPD1 than in NES (-) BPD1 and that AD, in particular, predicted NES. The mood fluctuations and increased appetite in AD seem to be consistent with the results of our study. In addition, eating disorder comorbidity, and especially binge eating disorder, was higher in patients with AD [31]. Although NES comorbidity was not examined in this previous study, the high incidence of other eating disorders in AD supports our findings.

Runfola et al. investigated the frequency of NES in 1636 university students using the EDE-Q and reported significantly higher scores in patients diagnosed with NES than in those without NES [32]. By contrast, in our study, we found no significant difference in the restriction item. This finding may be related to the higher impulsivity, even in the euthymic period, in the BPD group [33]. A study conducted in 233 pre-bariatric surgery patients using EDE-Q documented a higher subscale of eating concern in patients with NES than in those without NES [34]. The level of eating concern scores in NES (+) BPD1 in the present study was similar to that reported in previous studies. Furthermore, our results suggest that the presence of eating concern may predict NES and that a strong relationship exists between NES and eating concern. Higher levels of binge eating scores in the NES (+) BPD1 group may support the results of  Tu et al.  suggesting “a  strong  urge  to  eat  during  the night” in the proposed NES criteria might also be similar to “loss of control” (one of the two criteria of binge-eating) in Bulimia Nervosa (BN), sand NES might have several dimensions which overlap with BN [35].

Küçükgöncü et al. in psychiatric patients reported results similar to ours, as atypical antipsychotic use was significantly higher in patients with NES [24]. Additionally a case of sleep-related eating disorder induced by aripiprazole has been reported [36].  However, the study conducted by Saraçlı et al. revealed no difference between patients diagnosed with NES and patients without NES in terms of their antipsychotic use [26]. The inclusion of non-bipolar patients in that study may be the reason for the difference.

The available literature indicates a possible association between NES with obesity and high BMI [9]. In our sample, however, we found no significant difference in terms of BMI between patients with and without NES. Examination of several studies conducted on outpatients receiving psychiatric treatment reveals no difference in terms of BMI between those with and without NES [11,25,26,37,38]. Prospective studies are needed to evaluate this relationship further.

 

Conclusions

The strength of our study is that the patients evaluated were diagnosed as NES by clinical interviews as well as with scales. One limitation is that the cross-sectional evaluation of the cases and the patients being euthymic during evaluation decrease the generalizability of the results. Other limitations are the lack of a definite cause and effect relationship, the lack of comparative studies due to the lack of or few studies in the same population, and the lack of opportunity to compare treated and untreated groups.

In subjects with BPD1, the presence of AD, the use of atypical antipsychotics, and eating anxiety were identified as significant determinants of NES. These findings may have implications for the choice of treatment and the course of the disease. Studies comparing normal controls and BPD1 are viewed as very promising for the conceptualization of BPD1.    

 

Acknowledgments

The research data were published as an oral research presentation in the volume of the 11th International Congress on Psychopharmacology & 7th International Symposium on Child and Adolescent Psychopharmacology Abstracts 2019 of the Journal Psychiatry and Clinical Psychopharmacology.

    Conflicts of Interest

The authors declare no conflict of interest.

 

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