Gastrointestinal Bleeding in COVID-19 Patients: A Systematic Review with Meta-Analysis

The novel coronavirus disease 2019 (COVID-19) has been reported to affect the gastrointestinal system with a variety of symptoms, including bleeding. The prevalence of bleeding in these patients remains unclear. The aim of this meta-analysis is to estimate the rate of gastrointestinal bleeding in COVID-19 patients and its association with mortality. MEDLINE and Embase were searched through December 20, 2020. Studies reporting COVID-19 patients with and without gastrointestinal bleeding were included. Estimated prevalence with 95% confidence intervals (CI) was pooled; heterogeneity was expressed as I ². Metaregression analysis was performed to assess the impact of confounding covariates. Ten studies met the inclusion criteria and were included in the analysis. A total of 91887 COVID-19 patients were considered, of whom 534 reported gastrointestinal bleeding (0.6%) [409 (76.6%) upper and 121 (22.7%) lower gastrointestinal bleeding (UGIB and LGIB, resp.)]. The overall pooled gastrointestinal bleeding rate was 5% [95% CI 2-8], with high heterogeneity (I ² 99.2%); "small study effect" was observed using the Egger test (p=0.049). After removing two outlier studies, the pooled bleeding rate was 2% [95% CI 0-4], with high heterogeneity (I ² 99.2%), and no "small study effect" (p=0.257). The pooled UGIB rate was 1% (95% CI 0-3, I ² 98.6%, p=0.214), whereas the pooled LGIB rate was 1% (95% CI 0-2, I ² 64.7%, p=0.919). Metaregression analysis showed that overall estimates on gastrointestinal bleeding were affected by studies reporting different sources of bleeding. No significant association between gastrointestinal bleeding and mortality was found. In this meta-analysis of published studies, individuals with COVID-19 were found to be at risk for gastrointestinal bleeding, especially upper gastrointestinal bleeding.

Antibiotic prophylaxis in patients with cirrhosis: Current evidence for clinical practice

Patients with cirrhosis show an increased susceptibility to infection due to disease-related immune-dysfunction. Bacterial infection therefore represents a common, often detrimental event in patients with advanced liver disease, since it can worsen portal hypertension and impair the function of hepatic and extra-hepatic organs. Among pharmacological strategies to prevent infection, antibiotic prophylaxis remains the first-choice, especially in high-risk groups, such as patients with acute variceal bleeding, low ascitic fluid proteins, and prior episodes of spontaneous bacterial peritonitis. Nevertheless, antibiotic prophylaxis has to deal with the changing bacterial epidemiology in cirrhosis, with increased rates of gram-positive bacteria and multidrug resistant rods, warnings about quinolones-related side effects, and low prescription adherence. Short-term antibiotic prophylaxis is applied in many other settings during hospitalization, such as before interventional or surgical procedures, but often without knowledge of local bacterial epidemiology and without strict adherence to antimicrobial stewardship. This paper offers a detailed overview on the application of antibiotic prophylaxis in cirrhosis, according to the current evidence.

Tumor-Associated Macrophages and Inflammatory Microenvironment in Gastric Cancer: Novel Translational Implications

Gastric cancer (GC) represents the fifth most frequently diagnosed cancer worldwide, with a poor prognosis in patients with advanced disease despite many improvements in systemic treatments in the last decade. In fact, GC has shown resistance to several treatment options, and thus, notable efforts have been focused on the research and identification of novel therapeutic targets in this setting. The tumor microenvironment (TME) has emerged as a potential therapeutic target in several malignancies including GC, due to its pivotal role in cancer progression and drug resistance. Therefore, several agents and therapeutic strategies targeting the TME are currently under assessment in both preclinical and clinical studies. The present study provides an overview of available evidence of the inflammatory TME in GC, highlighting different types of tumor-associated cells and implications for future therapeutic strategies.

Clinical impact of sarcopenia assessment in patients with liver cirrhosis

Introduction: Sarcopenia is defined as loss of skeletal muscle mass, strength, and function, and it is associated with increased morbidity and mortality in patients with chronic liver disease.Areas covered: The aim of this review is to provide a detailed report on the pathophysiological mechanisms underlying sarcopenia in cirrhotic patients, the several imaging methods available for the assessment of sarcopenia and the clinical studies evaluating the prognostic role of sarcopenia presence in cirrhotic patients.Expert opinion: Sarcopenia pathogenesis is complex and multifaceted, as chronic catabolic conditions, increased energy expenditure, reduced appetite, side effects of multiple therapies, alterations in circulating levels of hormones, low protein synthesis, presence of ascites or portosystemic shunts are all factors contributing to muscle atrophy in cirrhotic patients. Computed tomography scan is the most validated method to evaluate muscle mass and quality. Sarcopenia is associated with a higher rate waitlist mortality, hepatic encephalopathy, and lower quality of life in patients with liver cirrhosis. Future studies should make an effort to unify and validate liver disease-specific cutoffs for the definition of sarcopenia.

Gastric Melanoma of Unknown Primary

We describe a case of a patient with anemia referring to our Digestive Endoscopy Unit. Upper GI endoscopy revealed a polypoid lesion with an ulcerated central depression. Histopathological examination of the biopsy specimen taken during endoscopy revealed a gastric metastatic melanoma. The dermatologic inspection failed in finding the primary melanoma. The importance of endoscopic examination in the diagnostic process of metastatic patients with unknown primaries is highlited by this case.

Two-stage hepatectomy with radioembolization for bilateral colorectal liver metastases: A case report

BACKGROUND

Two-stage hepatectomy (TSH) is a well-established surgical technique, used to treat bilateral colorectal liver metastases (CRLM) with a small future liver remnant (FLR). However, in classical TSH, drop-out is reported to be around 25%-40%, due to insufficient FLR increase or progression of disease. Trans-arterial radioembolization (TARE) has been described to control locally tumor growth of liver malignancies such as hepatocellular carcinoma, but it has been also reported to induce a certain degree of contralateral liver hypertrophy, even if at a lower rate compared to portal vein embolization or ligation.

CASE SUMMARY

Herein we report the case of a 75-year-old female patient, where TSH and TARE were combined to treat bilateral CRLM. According to computed tomography (CT)-scan, the patient had a hepatic lesion in segment VI-VII and two other confluent lesions in segment II-III. Therefore, one-stage posterior right sectionectomy plus left lateral sectionectomy (LLS) was planned. The liver volumetry estimated a FLR of 38% (segments I-IV-V-VIII). However, due to a more than initially planned, extended right resection, simultaneous LLS was not performed and the patient underwent selective TARE to segments II-III after the first surgery. The CT-scan performed after TARE showed a reduction of the treated lesion and a FLR increase of 55%. Carcinoembryonic antigen and CA 19.9 decreased significantly. Nearly three months later after the first surgery, LLS was performed and the patient was discharged without any postoperative complications.

CONCLUSION

According to this specific experience, TARE was used to induce liver hypertrophy and simultaneously control cancer progression in TSH settings for bilateral CRLM.

Imaging Software-Based Sarcopenia Assessment in Gastroenterology: Evolution and Clinical Meaning

Sarcopenia is gaining attention as a negative prognostic factor in different fields of medicine, including chronic liver failure. However, the assessment of sarcopenia in patients with liver diseases is often neglected due to unawareness of reliable tools and methods and thus is limited to research studies. Cross-sectional imaging is a diffuse diagnostic tool and is commonly performed in patients with chronic liver failure. The last advancements in radiology image analysis using dedicated software allow an easy and standardized method to assess skeletal muscle volume. Several measures can be obtained from cross-sectional imaging analysis to evaluate sarcopenia in patients affected by chronic liver disease. We aimed to review the recent advances in imaging-based sarcopenia assessment, in particular in patients with chronic liver diseases. As a result, we found that the skeletal muscle index (SMI) seems to be a reliable method to assess sarcopenia in cirrhotic patients. Even if further studies are needed to validate proper cut-offs for each clinical endpoint, physicians are invited to consider the assessment of sarcopenia in the work-up of patients with chronic liver disease.

Non-Celiac Gluten Sensitivity in the Context of Functional Gastrointestinal Disorders

Gluten-free diets are increasingly chosen in the Western world, even in the absence of a diagnosis of celiac disease. Around 10% of people worldwide self-report gluten-related complaints, including intestinal and extra-intestinal symptoms. In most cases, these subjects would be labeled as patients suffering from irritable bowel syndrome (IBS) who place themselves on a gluten-free diet even in the absence of celiac disease. In some instances, patients report a clear benefit by avoiding gluten from their diet and/or symptom worsening upon gluten reintroduction. This clinical entity has been termed non-celiac gluten sensitivity (NCGS). The symptoms referred by these patients are both intestinal and extra-intestinal, suggesting that similarly to functional gastrointestinal disorders, NCGS is a disorder of gut-brain interaction. It remains unclear if gluten is the only wheat component involved in NCGS. The mechanisms underlying symptom generation in NCGS remain to be fully clarified, although in the past few years, the research has significantly moved forward with new data linking NCGS to changes in gut motility, permeability and innate immunity. The diagnosis is largely based on the self-reported reaction to gluten by the patient, as there are no available biomarkers, and confirmatory double-blind challenge protocols are unfeasible in daily clinical practice. Some studies suggest that a small proportion of patients with IBS have an intolerance to gluten. However, the benefits of gluten-free or low-gluten diets in non-celiac disease-related conditions are limited, and the long-term consequences of this practice may include nutritional and gut microbiota unbalance. Here, we summarize the role of gluten in the clinical features, pathophysiology, and management of NCGS and disorders of gut-brain interaction.

Prognostic role of nutritional status in elderly patients hospitalized for COVID-19: a monocentric study

Background

Symptomatic severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection incidence is higher in the elderly patients. Pre-existing geriatric conditions such as comorbidity and frailty seem related to worse hospital outcomes.

Aims

To assess the role of nutritional status as an independent prognostic factor for in-hospital death in elderly patients.

Methods

Consecutive elderly patients (age > 65 years) hospitalized for novel coronavirus disease (COVID-19) were enrolled. Demographics, laboratory and comorbidity data were collected. Nutritional status was evaluated using the Geriatric Nutritional Risk Index (GNRI). Uni- and multivariate Cox regression analyses to evaluate predictors for in-hospital death were performed.

Results

One hundred and nine hospitalized elderly patients (54 male) were consecutively enrolled. At univariate analysis, age (HR 1.045 [CI 1.008–1.082]), cognitive impairment (HR 1.949 [CI 1.045–3.364]), C-reactive protein (HR 1.004 [CI 1.011–1.078]), lactate dehydrogenases (HR 1.003 [CI 1.001–1.004]) and GNRI moderate–severe risk category (HR 8.571 [CI 1.096–67.031]) were risk factors for in-hospital death, while albumin (HR 0.809 [CI 0.822–0.964]), PaO₂/FiO₂ ratio (HR 0.996 [CI 0.993–0.999]) and body mass index (HR 0.875 [CI 0.782–0.979]) were protective factors. Kaplan–Meier survival curves showed a significative higher survival in patients without GNRI moderate or severe risk category (p = 0.0013).

At multivariate analysis, PaO₂/FiO₂ ratio (HR 0.993 [CI 0.987–0.999], p = 0.046) and GNRI moderate–severe risk category (HR 9.285 [1.183–72.879], p = 0.034) were independently associated with in-hospital death.

Conclusion

Nutritional status assessed by GNRI is a significative predictor of survival in elderly patients hospitalized for COVID-19. The association between GNRI and PaO₂/FiO₂ ratio is a good prognostic model these patients.

Impact of COVID-19 outbreak on clinical practice and training of young gastroenterologists: A European survey

BACKGROUND

SARS-CoV-2 disease (COVID-19) is a major challenge for the healthcare system and physicians, imposing changes in daily clinical activity.

AIMS

we aimed to describe what European trainees and young gastroenterologists know about COVID-19 and identify training gaps to implement educational programs.

METHODS

A prospective web-based electronic survey was developed and distributed via e-mail to all members of the Italian Young Gastroenterologist and Endoscopist Association and to European representatives.

RESULTS

One hundred and ninety-seven subjects participated in the survey, of whom 14 (7.1%) were excluded. The majority were gastroenterologists in training (123, 67.7%) working in institutions with COVID-19 inpatients (159, 86.9%), aged ≤30 years (113, 61.8%). The activity of Gastroenterology Units was restricted to emergency visits and endoscopy, with reductions of activities of up to 90%. 84.5% of participants felt that the COVID-19 outbreak impacted on their training, due to unavailability of mentors (52.6%) and interruption of trainee's involvement (66.4%). Most participants referred absence of training on the use of personal protective equipment, oxygen ventilation systems and COVID-19 therapies.

CONCLUSION

COVID-19 outbreak significantly impacted on gastroenterologists' clinical activity. The resources currently deployed are inadequate, and therefore educational interventions to address this gap are warranted in the next future.

Complete Remission of Advanced Hepatocellular Carcinoma Treated with Sorafenib and Concomitant Appearance of IgG4- related Diseases. A Case Report

Sorafenib is currently the gold standard therapy for palliative treatment of advanced hepatocellular carcinoma (HCC) in patients with compensated liver disease. There are few cases reported in literature describing patients with HCC achieving a complete remission (CR) due to Sorafenib therapy. We report the case of a 62-year old patient who obtained CR despite single, long drug discontinuation and kept it without any maintenance therapy. Furthermore, this is the first case describing the onset of a likely IgG4-related retroperitoneal fibrosis and cholangitis during Sorafenib administration. Further studies are required to define the predictors of a good response to Sorafenib and to codify a therapeutic maintenance regimen for patients who achieve CR.

Is Ultrasound Elastography Useful in Predicting Clinically Relevant Pancreatic Fistula After Pancreatic Resection?: A Systematic Review and Meta-analysis

OBJECTIVES

Ultrasound (US) elastography has been proposed for the non-invasive prediction of clinically relevant pancreatic fistula (CR-POPF) in patients undergoing pancreatic resection. We aimed to perform a systematic review with meta-analysis to assess the diagnostic value of US elastography in predicting CR-POPF.

METHODS

MEDLINE via PubMed, Ovid Embase, Scopus, and Cochrane Library databases, and abstracts of international conference proceedings were searched up to April 20, 2020. Studies assessing the performance of abdominal US elastography in predicting CR-POPF in patients undergoing pancreatic resection were included. The quality of the studies was assessed using Quality Assessment of Diagnostic Accuracy Studies.

RESULTS

Five studies, including 247 patients who underwent partial pancreatic resection of whom 72 patients experiencing CR-POPF, were selected. All studies performed US elastography in different pancreatic sites. The pooled mean strain value was lower in pancreatic segments of patients experiencing CR-POPF than in those without, with a pooled weighted mean difference of -0.187 (95% confidence intervals, -0.303 to -0.071; P = 0.002). There was low heterogeneity between studies (I = 7.6%), and all studies were at "high risk" or "unclear risk" of bias.

CONCLUSIONS

This study provides evidence that US elastography values are statistically significantly lower in patients experiencing CR-POPF.

Probiotics, Prebiotics and Other Dietary Supplements for Gut Microbiota Modulation in Celiac Disease Patients

To date, the only available treatment for celiac disease (CD) patients is a life-lasting gluten-free diet (GFD). Lack of adherence to the GFD leads to a significant risk of adverse health consequences. Food cross-contamination, nutritional imbalances, and persistent gastrointestinal symptoms are the main concerns related to GFD. Moreover, despite rigid compliance to GFD, patients struggle in achieving a full restoring of the gut microbiota, which plays a role in the nutritive compounds processing, and absorption. Pivotal studies on the supplementation of GFD with probiotics, such as Bifidobacterium and Lactobacilli, reported a potential to restore gut microbiota composition and to pre-digest gluten in the intestinal lumen, reducing the inflammation associated with gluten intake, the intestinal permeability, and the cytokine and antibody production. These findings could explain an improvement in symptoms and quality of life in patients treated with GFD and probiotics. On the other hand, the inclusion of prebiotics in GFD could also be easy to administer and cost-effective as an adjunctive treatment for CD, having the power to stimulate the growth of potentially health-promoting bacteria strains. However, evidence regarding the use of prebiotics and probiotics in patients with CD is still insufficient to justify their use in clinical practice.

Non-invasive tests for the prediction of primary hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignancies in the world and it is one of the main complications of cirrhosis and portal hypertension. Even in the presence of a well-established follow-up protocol for cirrhotic patients, to date poor data are available on predictive markers for primary HCC occurrence in the setting of compensated advanced chronic liver disease patients (cACLD). The gold standard method to evaluate the prognosis of patients with cACLD, beyond liver fibrosis assessed with histology, is the measurement of the hepatic venous pressure gradient (HVPG). An HVPG ≥10 mmHg has been related to an increased risk of HCC in cACLD patients. However, these methods are burdened by additional costs and risks for patients and are mostly available only in referral centers. In the last decade increasing research has focused on the evaluation of several, simple, non-invasive tests (NITs) as predictors of HCC development. We reviewed the currently available literature on biochemical and ultrasound-based scores developed for the non-invasive evaluation of liver fibrosis and portal hypertension in predicting primary HCC. We found that the most reliable methods to assess HCC risk were the liver stiffness measurement, the aspartate aminotransferase to platelet ratio index score and the fibrosis-4 index. Other promising NITs need further investigations and validation for different liver disease aetiologies.

Spleen stiffness measurement for assessing the response to β-blockers therapy for high-risk esophageal varices patients

BACKGROUND

Non-selective β-blocker (NSBB) therapy is the treatment of choice for primary prophylaxis of cirrhotic patients with high-bleeding risk esophageal varices (HRV). The hemodynamic response to NSBB is assessed by the measurement of the hepatic venous pressure gradient (HVPG). Recently, liver and spleen stiffness measurements (LSM and SSM) were proposed as non-invasive surrogates of HVPG. We aimed to evaluate LSM and SSM changes for assessing hemodynamic response in these patients.

METHODS

Cirrhotic patients with HRV were prospectively enrolled and evaluated at our Department before starting NSBB and after 3 months. Correlation between changes (delta) of HVPG after NSBB treatment and those of LSM or SSM by transient elastography was performed.

RESULTS

From the initial 59 patients considered for the study, 20 were finally included in the analysis. Fifteen (15) patients reached hemodynamic response to NSBB according to HVPG. Changes in LSM did not correlate with changes in HVPG (r = 0.107, p value = 0.655), unlike changes in SSM (r = 0.784, p value < 0.0001). Delta SSM presented excellent accuracy in identifying HVPG responders (AUROC 0.973; 95% CI 0.912-1). The best cut-off for delta SSM to identify responders was -10% (sensitivity 100%, specificity 60%, NPV 100% and PPV 90%).

CONCLUSIONS

SSM could be a reliable non-invasive test for the assessment of hemodynamic response to NSBB therapy as primary prophylaxis for HRV. Similar to HVPG, SSM reduction ≥ 10% is able to assess hemodynamic response.

Gastric Cancer Staging: Is It Time for Magnetic Resonance Imaging?

Gastric cancer (GC) is a common cancer worldwide. Its incidence and mortality vary depending on geographic area, with the highest rates in Asian countries, particularly in China, Japan, and South Korea. Accurate imaging staging has become crucial for the application of various treatment strategies, especially for curative treatments in early stages. Unfortunately, most GCs are still diagnosed at an advanced stage, with the peritoneum (61-80%), distant lymph nodes (44-50%), and liver (26-38%) as the most common metastatic locations. Metastatic disease is limited to the peritoneum in 58% of cases; in nonperitoneal distant metastases, the most involved GC metastasization site is the liver (82%). The eighth edition of the tumor-node-metastasis staging system is the most commonly used system for determining GC prognosis. Endoscopic ultrasonography, computed tomography, and 18-fluorideoxyglucose positron emission tomography are historically the most accurate imaging techniques for GC staging. However, studies have recently shown renewed interest in magnetic resonance imaging (MRI) as a useful tool in GC staging, especially for distant metastasis assessment. The technical improvement of diffusion-weighted imaging and the increasing use of hepatobiliary contrast agents have been shown to increase the diagnostic performance of MRI, particularly for detecting peritoneal and liver metastasis. However, no principal oncological guidelines have included the use of MRI as a first-line technique for distant metastasis evaluation during the GC staging process, such as the National Comprehensive Cancer Network Guidelines. This review analyzed the role of the principal imaging techniques in GC diagnosis and staging, focusing on the potential role of MRI, especially for assessing peritoneal and liver metastases.

CT-scan fat halo sign in a patient with abdominal mass and constipation

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Spleen stiffness mirrors changes in portal hypertension after successful interferon-free therapy in chronic-hepatitis C virus patients

AIM

To investigate changes in spleen stiffness measurements (SSMs) and other non-invasive tests (NITs) after treatment with direct-acting antivirals (DAAs) and identify predictors of SSM change after sustained virological response (SVR).

METHODS

We retrospectively analysed 146 advanced-chronic liver disease (ACLD) patients treated with DAA with available paired SSM at baseline and SVR24. Liver stiffness (LSM), spleen diameter (SD), platelet count (PLT) and liver stiffness-spleen diameter to platelet ratio score(LSPS) were also investigated. LSM ≥ 21 kPa was used as a cut-off to rule-in clinically significant portal hypertension (CSPH). SSM reduction > 20% from baseline was defined as significant.

RESULTS

SSM significantly decreased at SVR24, in both patients with and without CSPH; in 44.8% of cases, SSM reduction was > 20%. LSPS significantly improved in the entire cohort at SVR24; SD and PLT changed significantly only in patients without CSPH. LSM significantly decreased in 65.7% of patients and also in 2/3 patients in whom SSM did not decrease. The independent predictor of decreased SSM was median relative change of LSM. CSPH persisted in 54.4% patients after SVR. Delta LSM and baseline SSM were independent factors associated with CSPH persistence.

CONCLUSION

SSM and other NITs significantly decrease after SVR, although differently according to the patient’s clinical condition. SSM faithfully reflects changes in portal hypertension and could represent a useful NIT for the follow-up of these patients.

Gut Microbiota and Celiac Disease

Recent evidence regarding celiac disease has increasingly shown the role of innate immunity in triggering the immune response by stimulating the adaptive immune response and by mucosal damage. The interaction between the gut microbiota and the mucosal wall is mediated by the same receptors which can activate innate immunity. Thus, changes in gut microbiota may lead to activation of this inflammatory pathway. This paper is a review of the current knowledge regarding the relationship between celiac disease and gut microbiota. In fact, patients with celiac disease have a reduction in beneficial species and an increase in those potentially pathogenic as compared to healthy subjects. This dysbiosis is reduced, but might still remain, after a gluten-free diet. Thus, gut microbiota could play a significant role in the pathogenesis of celiac disease, as described by studies which link dysbiosis with the inflammatory milieu in celiac patients. The use of probiotics seems to reduce the inflammatory response and restore a normal proportion of beneficial bacteria in the gastrointestinal tract. Additional evidence is needed in order to better understand the role of gut microbiota in the pathogenesis of celiac disease, and the clinical impact and therapeutic use of probiotics in this setting.

Pathophysiology and Therapeutic Strategies for Symptomatic Uncomplicated Diverticular Disease of the Colon

Colonic diverticulosis imposes a significant burden on industrialized societies. The current accepted causes of diverticula formation include low fiber content in the western diet with decreased intestinal content and size of the lumen, leading to the transmission of muscular contraction pressure to the wall of the colon, inducing the formation of diverticula usually at the weakest point of the wall where penetration of the blood vessels occurs. Approximately 20 % of the patients with colonic diverticulosis develop abdominal symptoms (i.e., abdominal pain and discomfort, bloating, constipation, and diarrhea), a condition which is defined as symptomatic uncomplicated diverticular disease (SUDD). The pathogenesis of SUDD symptoms remains uncertain and even less is known about how to adequately manage bowel symptoms. Recently, low-grade inflammation, altered intestinal microbiota, visceral hypersensitivity, and abnormal colonic motility have been identified as factors leading to symptom development, thus changing and improving the therapeutic approach. In this review, a comprehensive search of the literature regarding on SUDD pathogenetic hypotheses and pharmacological strategies was carried out. The pathogenesis of SUDD, although not completely clarified, seems to be related to an interaction between colonic microbiota alterations, and immune, enteric nerve, and muscular system dysfunction (Cuomo et al. in United Eur Gastroenterol J 2:413-442, 2014). Greater understanding of the inflammatory pathways and gut microbiota composition in subjects affected by SUDD has increased therapeutic options, including the use of gut-directed antibiotics, mesalazine, and probiotics (Bianchi et al. in Aliment Pharmacol Ther 33:902-910, 2011; Comparato et al. in Dig Dis Sci 52:2934-2941, 2007; Tursi et al. in Aliment Pharmacol Ther 38:741-751, 2013); however, more research is necessary to validate the safety, effectiveness, and cost-effectiveness of these interventions.