A study estimates the frequency and clinical correlates of GI symptoms during depressive episodes in a large, nationwide sample of patients with MDD in China.
MDD is a highly prevalent mental health condition. There is evidence that, in China, co-occurring somatic symptoms, including headache and stomachache might contribute to misdiagnosis of depression and delayed treatment.1 Previous studies of somatic symptoms in MDD have yielded conflicting or inconclusive results, although there is some evidence for increased gastrointestinal symptoms.2 Given growing evidence for the microbiota-gut-brain axis in depressive disorders, GI symptoms might be a marker for dysbiosis in MDD.3
Huang and colleagues estimated the frequency and clinical correlates of GI symptoms during depressive episodes in a large, nationwide sample of patients with MDD in China.4 They hypothesized that the presence of GI symptoms would be associated with comorbidity in MDD, including insomnia, hopelessness, anxiety, and suicidal ideation. Study participants were from the National Survey on Symptomatology of Depression (NSSD) in China, which included inpatient and outpatient participants 18 years or older with a current DSM-IV episode of MDD.
Exclusion criteria were a lifetime diagnosis of bipolar or psychotic disorder, imminent risk of suicide or homicide, received electroconvulsive therapy within the past month, current pregnancy or breastfeeding, and substance use disorder over the past year. Patients were interviewed by trained psychiatrists on a broad range of symptoms, including depression and somatic symptoms, over the previous 2 weeks. Sociodemographic and clinical characteristics between patients with different severity of GI symptoms were performed with 1-way analysis of variance. Multiple linear regression analysis was used to analyze associations between GI symptoms and psychopathology, adjusting for potential confounding factors.
A total of 3256 patients (mean age 41, 40% male) were included in the analyses. Of those, 1750 patients (71%) had GI symptoms, with a frequency of several days/week for 38%, more than half of days for 23%, and almost daily for 10%. Patients with more GI symptoms had a significantly increased prevalence of anxiety; insomnia; poor concentration; limb and body pain; hopelessness; anger and irritability; and feelings of failure. In linear regression, suicidal ideation, anxiety, insomnia, anger, feelings of failure, and body pain were independently and significantly associated with GI symptoms in patients with MDD (Table).
The authors concluded that more than 70% of patients with MDD reported GI symptoms during depressive episodes. Strengths of the study include the large, nationwide sample. Limitations include the cross-sectional nature of the study design, unmeasured and residual confounding factors, as well as the absence of data on specific GI symptoms. These findings are germane to investigations of the microbiota-gut-brain axis in depressive disorders.
“Mr S” is a 26-year-old Caucasian male with a history of recurrent major depressive disorder (MDD) and anxiety disorder. The onset of his depressive illness began when he was 19 years old. For the past 2 to 3 months during an exacerbation of his depression, he reports significant nausea and vomiting on a daily basis, particularly in the morning, which was not attributable to increased anxiety. Mr S reports that his gastrointestinal (GI) symptoms did not respond to treatment with either H-2 blockers or a proton-pump inhibitor. Subsequently, his antidepressant was changed to a different selective serotonin reuptake inhibitor, and a low-dose long-acting benzodiazepine was also added for anxiety. Over the next month, he reported significant improvement in not only mood and anxiety, but also nausea and vomiting, such that he was able to return to full-time employment.
The Bottom Line
Gastrointestinal symptoms are common in the clinical presentation of MDD. GI symptoms may be associated with the onset and clinical severity of depression, which could be a potential ancillary indicator in the management of MDD.
Dr Miller is professor in the Department of Psychiatry and Health Behavior, Augusta University, Augusta, Georgia. He is on the Editorial Board and serves as the schizophrenia section chief for Psychiatric TimesTM. The author reports that he receives research support from Augusta University, the National Institute of Mental Health, the Brain and Behavior Research Foundation, and the Stanley Medical Research Institute.
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2. Harshaw C. Interoceptive dysfunction: toward an integrated framework for understanding somatic and affective disturbance in depression. Psychol Bull. 2015;141(2):311-363.
3. Bruce-Keller AJ, Salbaum JM, Berthoud HR. Harnessing gut microbes for mental health: getting from here to there. Biol Psychiatry. 2018;83(3):214-223.
4. Guo F, Cai J, Jia Y, et al. Symptom continuum reported by affective disorder patients through a structure-validated questionnaire. BMC Psychiatry. 2020;20(1):207.