Findings:
This is the first systematic review to specifically address whether or not psychological interventions can reduce healthcare utilization in patients with medically unexplained symptoms (MUS). CBT-based interventions have been shown previously to reduce physical symptoms and possibly also psychological distress and functional status in patients with somatic symptom disorders (Kroenke and Swindle 2000). This paper, however, found that CBT-based interventions (compared with active controls, treatment as usual, and waiting list controls), had only a small impact on reducing the number of healthcare contacts and lowering medication use. Furthermore, no significant effect was seen on medical diagnostic investigations and overall healthcare cost. These findings are consistent with previous Cochrane reviews on MUS (van Dessel et al. 2014), but less positive than those reviewing chronic pain alone (Williams et al. 2012), suggesting that a more condition-specific intervention with clearer underpinning theory may be able to achieve more consistent changes in this outcome.

Strengths and limitations:
The label “MUS” is heterogeneous, encapsulating multiple conditions and symptoms, and may risk missing studies described in specific terms (though this search built on a previous review, van Dessel et al. 2014, and is transparent). The heterogeneity between studies was moderate to high in most analysis, but is not expected to have had significant implications for result interpretation except in the case of medication usage (where assessment methods varied conceptually and metrically). Thus interpretation of this finding in particular should be cautious.

Relevance:
Patients with (MUS) have high levels of healthcare use, and are commonly encountered in medical settings. Physicians often find it challenging to negotiate the risks of over- vs. under-investigating and treating such patients, as well as costs. The C-L psychiatrist is in a unique position to identify and carry out effective interventions geared toward reducing not only patient distress, but also burden on the general healthcare system.

Type of study:
(http://ebm.bmj.com/content/early/2016/06/23/ebmed-2016-110401): Systematic review and meta-analysis

Other relevant references:
Kroenke K, Swindle R. Cognitive-behavioral therapy for somatization and symptom syndromes: a critical review of controlled clinical trials. Psychother Psychosom 2000; 69(4):205-15.
Van Dessel N, den Boeft M, van der Wouden JC, et al. Non-pharmacological interventions for somatoform disorders and medically unexplained physical symptoms (MUPS) in adults. Cochrane Database Syst Rev 2014; (11): CD011142.
Williams AC, Eccleston C, Morley S. Psychological therapies for the management of chronic pain (excluding headache) in adults. Cochrane Databse Syst Rev 2012; (11): CD007407.

Findings:
This neuro-imaging study showed that patients with somatic symptom disorder showed increased functional connectivity, compared to age- and sex-matched healthy controls, in the sensorimotor network (SMN), default mode network (DMN), and salience network. These changes were correlated with scoring on the Somato-Sensory Amplification Scale (SSAS). Previous studies on somatic symptom disorders with prominent pain have shown strong connections between the SMN and high-order networks such as the DMN and salience network (Otti et al. 2013, Zhao et al. 2017). These collective findings suggest that SSD patients may have alterations of sensory-discriminative processing of pain and other somatic symptoms, which in closely related to cognition, self-referential thoughts, attention, and affective salience. The authors also found evidence for possible attentional deficits in patients with SSD, which could lead to misperception of external stimuli and failure to regulate bodily functions aimed at interactions with such stimuli.

Strengths and limitations:
This study had a small number of participants which makes it difficult to generalize the obtained result due to a high risk for type 1 and 2 errors. The sample was also heterogeneous in terms of gender, making it difficult to examine different populations separately and/or control for gender. Since gender is relevant in the epidemiology of SSD, differences in brain activity between men and women would be interesting to investigate. The cross-sectional design of the current study did not differentiate the causes from the results of the changes in functional connectivity. Finally, there was no control group of patients with objectively established medical illness with comparable levels of somatic symptoms who did not meet criteria for SSD, making it difficult to conclude whether these findings are specific to SSD or are present in patients with any type of somatic symptomatology.

Relevance:
Patients with SSD have high levels of psychological distress and healthcare utilization. Although there has been progress in the study of patients with SSD, biomarkers have not yet been established to identify patients and the neurobiology underlying this condition is not yet clear. This paper contributes to the growing body of literature which aims to establish neurobiological mechanisms (and particularly alterations in brain functional connectivity) that may play a critical role in SSD and assist with development of novel treatment strategies.

Type of study:
(http://ebm.bmj.com/content/early/2016/06/23/ebmed-2016-110401): Cohort study