Adult Eating Disorders Service, Ward S3 Inpatients, Addenbrooke's Hospital, Cambridge, UK.
Department of Medicine, Cambridge Institute of Therapeutic Immunology & Infectious Disease, University of Cambridge, Cambridge, UK.
Brain Behav. 2024 Sep;14(9):e70014. doi: 10.1002/brb3.70014.
Anorexia nervosa has the highest mortality rate among psychiatric illnesses. Current treatments remain ineffective for a large fraction of patients. This may be due to unclear mechanisms behind its development and maintenance. Studies exploring the role of the gut microbiome have revealed inconsistent evidence of dysbiosis. This article aims to investigate changes in the gut microbiome, particularly, mean differences in the Firmicutes to Bacteroidetes ratio, in adolescent and adult individuals with anorexia nervosa following inpatient treatment.
Longitudinal studies investigating gut microbiome composition in inpatient populations of anorexia nervosa before and after treatment were systematically reviewed. Additionally, gut microbiome compositions were characterized in three acute anorexia nervosa inpatients early after admission and after 4-12 weeks of treatment.
Review results indicated an increase in the Firmicutes to Bacteroidetes ratio in individuals with anorexia nervosa after treatment. These however did not match values of their healthy counterparts. In the case-series samples, the reverse occurred with samples taken 4 weeks after treatment. In the patient who provided an extra sample 12 weeks after treatment, similar results to the studies included in the review were observed. Furthermore, Firmicutes to Bacteroidetes ratio values in the case-series samples were notably higher in the two patients who had chronic anorexia nervosa.
Differences in methodologies, small sample sizes, and insufficient data limited the generalizability of the outcomes of the reviewed studies. Results suggest a potentially unique microbiome signature in individuals with chronic anorexia nervosa, which may explain different outcomes in this group of patients.
神经性厌食症是精神疾病中死亡率最高的疾病。目前的治疗方法对很大一部分患者仍然无效。这可能是由于其发展和维持的机制不明确。探索肠道微生物组作用的研究表明，肠道微生物失调的证据不一致。本文旨在研究肠道微生物组的变化，特别是神经性厌食症青少年和成年患者在住院治疗后的厚壁菌门到拟杆菌门比值的平均差异。
系统回顾了关于神经性厌食症住院患者在治疗前后肠道微生物组组成的纵向研究。此外，还对三名急性神经性厌食症住院患者在入院后早期和治疗 4-12 周后进行了肠道微生物组组成的特征描述。
综述结果表明，神经性厌食症患者在治疗后厚壁菌门到拟杆菌门比值增加。然而，这些值与健康对照组的不匹配。在病例系列样本中，在治疗后 4 周时则相反。在接受额外样本 12 周后治疗的患者中，观察到与综述中纳入的研究相似的结果。此外，病例系列样本中的厚壁菌门到拟杆菌门比值在两名患有慢性神经性厌食症的患者中明显更高。
方法学差异、样本量小和数据不足限制了综述研究结果的普遍性。结果表明，慢性神经性厌食症患者的肠道微生物组可能存在独特的特征，这可能解释了该组患者的不同结果。
