Patterns of Cannabis Use in Patients With Cyclic Vomiting Syndrome

Cannabis Hyperemesis Syndrome in Children: A Review of Epidemiology, Pathology, Diagnosis, and Treatment

Cannabis remains one of the most frequently misused substances among adolescents. As recreational cannabis has proliferated across the United States, cannabis-related emergency department visits have increased. Cannabis hyperemesis syndrome, a variant of cyclic vomiting syndrome, has emerged as a recognized but poorly understood complication of chronic cannabis use among a subset of individuals. Cannabis hyperemesis syndrome is characterized by repeated cycles of abdominal pain, nausea, and vomiting refractory to standard antiemetics, with users reporting the compulsive use of hot showers to mitigate symptoms. Treatment modalities include intravenous fluid and electrolyte repletion, topical application of capsaicin, and the use of antidopaminergics (eg, droperidol, haloperidol).

Cannabis use patterns and association with hyperemesis: A comprehensive review

BACKGROUND

Cannabis use in the general population is prevalent and is rising because of increased acceptance of its use, legalization in most US states, and perceived health benefits. Cannabis product potency has dramatically increased with higher delta-9-tetrahydrocannabinol content. Cannabis has documented antiemetic properties and cannabinoid pharmaceuticals are used in disorders like chemotherapy-induced nausea and vomiting.

PURPOSE

Forty to eighty percent of cyclic vomiting syndrome (CVS) patients use cannabis products, which reportedly reduce stress as well as nausea and vomiting. Cannabinoid hyperemesis syndrome (CHS) has a presentation similar to CVS, but is associated with longstanding, high dose cannabis use, and is thought to be relieved by sustained cannabis abstinence. Most CHS patients have used cannabis on a daily or near-daily basis for more than 2 years. Compulsive hot-water bathing behaviors are reported by most CHS patients, but are not specific for this disorder as they are also noted by about half of CVS patients. Episodic vomiting associated with cannabis use contributes to extensive health resource use, including emergency department visits and inpatient hospitalizations, and impacts patients and their families negatively. Treatment for CHS overlaps with CVS although cannabis abstinence remains the cornerstone of its management. Challenges associated with cannabis use cessation in CHS include patient skepticism of the role of cannabis as a cause of symptoms, perceived benefits of cannabis, and a lack of other effective therapies. In this review, we highlight cannabis use patterns in the US and discuss diagnosis and management of CHS and gaps in knowledge about this disorder.

Cyclic vomiting syndrome: Future clinical and research priorities for: Special supplement/proceedings of 3rd international symposium

BACKGROUND

An increasing number of studies have explored the clinical features, epidemiology, pathophysiology, and management of cyclic vomiting syndrome (CVS). CVS is common in adults and children and negatively impacts patients, families, and the healthcare system. A related condition, cannabinoid hyperemesis syndrome (CHS), has been a focus of interest in the lay press and published literature.

PURPOSE

Clinical presentations of CVS have been defined by small series and expert opinion, but recent prospective studies are refining our understanding of the spectrum of emetic episodes and the breadth of comorbid conditions. Large cross-sectional population analyses are clarifying CVS prevalence and factors related to age, ethnicity, and geographic region. CVS pathophysiology is multifactorial with contributions from migraines, dysautonomia, endogenous cannabinoids, mitochondrial dysfunction, genetic abnormalities, and rapid gastric emptying. CVS treatment relies on antiemetics and antimigraine therapies to abort acute episodes coupled with prophylactic regimens employing neuromodulators and antiepileptics. CHS represents a challenge partly because of difficulties in achieving sustained cannabis abstinence. Benefits of other therapies in CHS remain poorly defined. Several areas warrant further scrutiny including better identification of CVS triggers and characterization of different CVS subsets including those with frequent severe episodes, refined description of epidemiology to allow targeting of populations predisposed to CVS development, rigorous definition of pathogenic factors to provide a foundation for exploratory studies of novel therapies, and conduct of controlled trials by multicenter collaborations to confirm benefits of existing and new therapies in development. Progress in these areas will be facilitated by generous governmental and industry support.

Acute care of cyclic vomiting syndrome and cannabinoid hyperemesis syndrome in the home and emergency department

BACKGROUND

Cyclic vomiting syndrome (CVS) and cannabinoid hyperemesis syndrome (CHS) are both characterized by episodic, acute transitions from asymptomatic states to highly symptomatic states of nausea, repetitive vomiting, and often severe abdominal pain. Patients with CVS and CHS face significant challenges to abort or mitigate episodes at home and often require emergency department (ED)-based care.

PURPOSE

This paper reviews the current treatment approach to abort acute CVS and CHS episodes at home and in ED settings. Multiple pharmacologic and nonpharmacologic interventions have been demonstrated to potentially abort CVS or CHS episodes. Systemic pharmacologic agents often used as abortive therapy include triptans, antiemetics, anxiolytics, NK-1 receptor antagonists, antipsychotics, sedatives in general, and various analgesic / anti-inflammatory medications. Nonsystemic, nonpharmacologic approaches include reducing external stimuli (quiet room, dim lights, etc.), and hot water bathing or the application of topical capsaicin cream. More research is needed to develop evidence-based, individualized abortive treatment plans, as well as to determine whether the abortive treatment for CVS requires a fundamentally different approach than for CHS. When home-based approaches fail, all patients with CVS or CHS should receive nonjudgmental, informed, and compassionate care in the ED to abort their episode. Patients with more severe forms of CVS/CHS who require more frequent ED utilization should develop care plans with their ED to assure predictable and effective treatment.

Endocannabinoid signaling in stress, nausea, and vomiting

BACKGROUND

Classical antiemetics that target the serotonin system may not be effective in treating certain nausea and vomiting conditions like cyclic vomiting syndrome (CVS) and cannabinoid hyperemesis syndrome (CHS). As a result, there is a need for better therapies to manage the symptoms of these disorders, including nausea, vomiting, and anxiety. Cannabis is often used for its purported antiemetic and anxiolytic effects, given regulation of these processes by the endocannabinoid system (ECS). However, there is considerable evidence that cannabinoids can also produce nausea and vomiting and increase anxiety in certain instances, especially at higher doses. This paradoxical effect of cannabinoids on nausea, vomiting, and anxiety may be due to the dysregulation of the ECS, altering how it maintains these processes and contributing to the pathophysiology of CVS or CHS.

PURPOSE

The purpose of this review is to highlight the involvement of the ECS in the regulation of stress, nausea, and vomiting. We discuss how prolonged cannabis use, such as in the case of CHS or heightened stress, can dysregulate the ECS and affect its modulation of these functions. The review also examines the evidence for the roles of ECS and stress systems' dysfunction in CVS and CHS to better understand the underlying mechanisms of these conditions.

Symptom Patterns in Adults With Cyclic Vomiting Syndrome: A 6-Month Prospective Observational Study

BACKGROUND

Data are limited on the natural history and symptom patterns of cyclic vomiting syndrome (CVS), a disorder of gut-brain interaction characterized by recurrent stereotypical vomiting, retching, and nausea episodes.

METHODS

A 6-month, observational, remote study prospectively assessed symptom patterns in adults with CVS using an electronic daily diary. Patients recorded their disease experience, including CVS symptoms and associated severity, in the daily diary. The study defined a CVS episode start as the first day of 5 or more vomiting and/or retching (V + R) events. Episode end was defined as the first day of ≥ 7 (prespecified main analysis) or ≥ 4 (sensitivity analysis) days without any diary V + R events.

KEY RESULTS

Eighty-eight of 93 (94.6%) enrolled patients (62 female; mean age, 37.7 years) had daily diary data recorded during the study; 61 (69.3%) patients had at least one episode. In the prespecified main analysis, 191 episodes (median, 0.6 per 30 diary days) were reported (median duration, 3.0 days); 17.8% of the episodes lasted > 10 days. In the sensitivity analysis, 248 episodes (median, 0.7 per 30 diary days) were reported (median duration, 2.0 days). Thirteen of 88 (14.8%) patients with diary data had interepisodic V + R (reported V + R events without meeting the threshold for study-defined episode). Other CVS-related (non-V + R) symptoms (most frequently nausea, abdominal pain, and sweating) were reported more frequently during the episode versus the interepisodic period.

CONCLUSIONS AND INFERENCES

This prospective longitudinal study shows marked heterogeneity of CVS episodes and highlights the need to better define and characterize episodes in these patients.

Cyclic vomiting syndrome: From pathophysiology to treatment

Cyclic vomiting syndrome (CVS) is a disorder characterized by recurrent and unpredictable episodes of intense vomiting, interspersed with periods of apparent wellbeing. This disorder, which primarily affects children and adolescents but can persist into adulthood, has recently been the subject of extensive study and analysis in the medical literature. The aim of the present review is to examine the most important aspects of the epidemiology, pathophysiology, subtypes, diagnostic criteria, and current management of CVS. Even though the exact etiology remains unknown, genetic factors (polymorphisms), nervous system alterations and autonomic dysregulation, and environmental factors (use and abuse of cannabinoids) are postulated as possible triggers. CVS has significant diagnostic challenges, given that there is no specific test for confirming its presence. Thorough evaluation of symptoms and the ruling out of other possible causes of recurrent vomiting are required. Management of CVS typically involves a multidisciplinary approach. Pharmacologic options are explored, such as antiemetics and preventive medications, as well as behavioral and psychologic support therapies. Treatment personalization is essential, adapting it to the individual needs of each patient. Despite advances in the understanding of CVS, it remains a significant clinical challenge. This disorder impacts the quality of life of those affected and their families, underscoring the ongoing need for research and the development of more effective treatment strategies.

Cannabinoid hyperemesis syndrome: Clinical trajectories and patterns of use three months following a visit to the emergency department

OBJECTIVES

Cannabinoid hyperemesis syndrome (CHS) is a clinical condition of cyclic vomiting, nausea, and abdominal pain associated with chronic cannabis use. Despite increased recognition of CHS, there are limited details on cannabis use practices and symptoms over time. Understanding what happens in the period surrounding the emergency department (ED) visit, including any changes in symptoms and cannabis use practices following the visit, can help inform the development of patient-centered interventions around cannabis use disorder for patients with CHS.

METHODS

A prospective observational cohort (n = 39) of patients with suspected CHS recruited from the ED at the time of a symptomatic cyclic vomiting episode was followed for 3 months. Disease progression, cannabis use practices, and health care utilization were monitored.

RESULTS

Participants reported high rates of persistent CHS symptoms (abdominal pain, nausea, or cyclic vomiting) in the 2-week period immediately following an ED visit with a median duration of 7 days. Cannabis use frequency and quantity were reduced immediately after the ED visit, but most participants returned to pre-ED visit cannabis use patterns within a few days. Recurrent ED visits for cyclic vomiting were reported by 25% of participants who completed follow-up during the 3-month follow-up period.

CONCLUSIONS

Participants continued to have ongoing symptoms after the ED visit, but most managed symptoms on their own and did not return to the ED. Longitudinal studies beyond 3 months are needed to better understand the clinical course of patients with suspected CHS.

RCEM best practice guideline: suspected cannabinoid hyperemesis syndrome in emergency departments

Cannabinoid hyperemesis syndrome (CHS) is an episodic syndrome of cyclic vomiting in the context of the prolonged use of cannabis. The Royal College of Emergency Medicine Toxicology Special Interest Group has produced guidance to support emergency medicine clinicians with the recognition and treatment of people experiencing CHS.Considerations regarding recognition, investigation and communication are discussed, and recommendations regarding treatment options (which include haloperidol and capsaicin) are made. There is a focus on making recommendations on the best available evidence.

Cannabis use in the United States and its impact on gastrointestinal health

In recent years, the legalization and social acceptability of cannabis use have increased in the United States. Concurrently, the prevalence of cannabis use has continued to rise, and cannabis products have diversified. There are growing concerns regarding the health effects of regular and high-potency cannabis use, and new research has shed light on its potentially negative effects. Here, we review evidence of the gastrointestinal (GI) effects of cannabis and cannabinoids. Dysregulation of the endocannabinoid system might contribute to various GI disorders, including irritable bowel syndrome and cyclic vomiting syndrome, and endocannabinoids have been found to regulate visceral sensation, nausea, vomiting, and the gut microbiome. Cannabis has been shown to have antiemetic properties, and the US Food and Drug Administration has approved cannabis-based medications for treating chemotherapy-induced nausea and vomiting. Yet, chronic heavy cannabis use has been linked to recurrent episodes of severe nausea and intractable vomiting (cannabinoid hyperemesis syndrome). Given the considerable heterogeneity in the scientific literature, it is unclear if cannabinoid hyperemesis syndrome is truly a distinct entity or a subtype of cyclic vomiting that is unmasked by heavy cannabis use and the associated dysregulation of the endocannabinoid system. The changes in cannabis legalization, availability, and public risk perceptions have outpaced research in this area and there is a need for robust, prospective, large-scale studies to understand the effects of cannabis use on GI health.

Cannabis use and cyclical vomiting syndrome: An open debate

INTRODUCTION

Cyclical vomiting syndrome (CVS) carries a significant financial burden on the U.S. healthcare system due to the recurrent emergency department visits and inpatient hospitalizations. We aimed to update the literature on the predictors of hospital utilization and readmission among individuals admitted with CVS.

METHODS

This is a retrospective nationwide study of patients hospitalized with a primary diagnosis of CVS. Using weighted data from the National Inpatient Sample (NIS) and the National Readmission Database (NRD), we conducted a multivariate regression analysis to assess predictors of length of stay (LOS), and 30-day readmission.

RESULTS

Primary admissions for CVS totaled 35,055 in the NIS, and 31,240 in the NRD. 2012 patients (6.4%) were readmitted within 30 days. On multivariate regression, cannabis use was associated with reduced LOS (adjusted Mean Difference (aMD) = -0.53 days, 95% CI: -0.68 to -0.38), and 30-day readmissions (adjusted Hazard Ratio (aHR) = 0.63, 95% CI: 0.54-0.73).

DISCUSSION

Cannabis use among CVS admissions was associated with reduced LOS and 30-day readmissions; these results could be in fact driven by Cannabis Hyperemesis Syndrome (CHS)-related hospitalizations and the effect of cannabis cessation on decreased symptomatology. ICD-10 coding for CHS should be transitioned to specific codes to improve the differentiation between CVS and CHS-related hospitalizations.

Cannabinoids and the Gastrointestinal Tract

The synthesis and degradation of endocannabinoids, location of cannabinoid (CB) receptors, and cannabinoid mechanisms of action on immune/inflammatory, neuromuscular, and sensory functions in digestive organs are well documented. CB2 mechanisms are particularly relevant in immune and sensory functions. Increasing use of cannabinoids in the United States is impacted by social determinants of health including racial discrimination, which is associated with tobacco and cannabis co-use, and combined use disorders. Several conditions associated with emesis are related to cannabinoid use, including cannabinoid hyperemesis or withdrawal, cyclic vomiting syndrome, and nausea and vomiting of pregnancy. Cannabinoids generally inhibit gastrointestinal motor function; yet they relieve symptoms in patients with gastroparesis and diverse nausea syndromes. Cannabinoid effects on inflammatory mechanisms have shown promise in relatively small placebo-controlled studies in reducing disease activity and abdominal pain in patients with inflammatory bowel disease. Cannabinoids have been studied in disorders of motility, pain, and disorders of gut-brain interaction. The CB2-receptor agonist, cannabidiol, reduced the total Gastroparesis Cardinal Symptom Index and increases the ability to tolerate a meal in patients with gastroparesis appraised over 4 weeks of treatment. In contrast, predominant-pain end points in functional dyspepsia with normal gastric emptying were not improved significantly with cannabidiol. The CB2 agonist, olorinab, reduced abdominal pain in inflammatory bowel disease in an open-label trial and in constipation-predominant irritable bowel syndrome in a placebo-controlled trial. Cannabinoid mechanisms alter inflammation in pancreatic and liver diseases. In conclusion, cannabinoids, particularly agents affecting CB2 mechanisms, have potential for inflammatory, gastroparesis, and pain disorders; however, the trials require replication and further understanding of risk-benefit to enhance use of cannabinoids in gastrointestinal diseases.

Plasma endocannabinoids and cannabimimetic fatty acid derivatives are altered in cyclic vomiting syndrome: The effects of sham feeding

Cyclic vomiting syndrome (CVS) is an underdiagnosed disorder of the gut-brain interaction. Our understanding of the pathophysiology of CVS is evolving. Here, we tested the hypotheses that: (1) the levels of endocannabinoids and related lipids are altered in CVS, and (2) cephalic-vagal stimulation drive changes in endolipid levels. Ten adult patients with CVS and eight healthy controls were included. Indirect measurements of parasympathetic (RFa) functions were performed with spectral analysis of heart rate variability and respiratory activity. Plasma levels of endocannabinoids and related lipids were measured at baseline and during a sham feeding. Values are reported as mean ± standard error of the mean and compared using t-test or ANOVA. CVS patients had a lower parasympathetic tone and response to the Valsalva maneuver and deep breathing than the controls. The baseline 2-Arachidonoylglycerol (2-AG) had a significantly higher concentration in CVS (5.9e-008 ± 3.7e-008 mol/L) than control (3.7e-008 ± 1.3e-008 mol/; p < 0.05). Sham feeding did not change the concentration of 2-AG. 2-oleoylglycerol (2-OG) was significantly higher in CVS than control and did not change with sham feeding. Levels of N-acylethanolamines, including anandamide (AEA), were not different in CVS vs control. After sham feeding, AEA showed a trend toward increasing (p = 0.08) in CVS, but not in control. With sham feeding, palmitoyl ethanolamine significantly increased in both CVS and control groups; oleoyl ethanolamine in CVS only, and stearoyl ethanolamine in the control group. Levels of endocannabinoids and related lipids are altered in CVS patients. Sham feeding affects endogenous signaling lipids in a disease and time-dependent manner.

Cannabinoid hyperemesis syndrome presenting with ventricular bigeminy

The is a case of a 28-year-old male presenting to an emergency department (ED) via emergency medical services (EMS) with a chief complaint of "gastritis." He was noted to have bigeminy on the pre-arrival EMS electrocardiogram. He was ultimately diagnosed with cannabinoid hyperemesis syndrome (CHS). CHS is becoming an exceedingly common emergency department presentation due to the poorly regulated but widespread availability of cannabis products. The authors discuss a case of CHS and ventricular bigeminy.

Cannabis Use Patterns and Whole-Blood Cannabinoid Profiles of Emergency Department Patients With Suspected Cannabinoid Hyperemesis Syndrome

STUDY OBJECTIVES

The objectives of this study were to characterize the detailed cannabis use patterns (eg, frequency, mode, and product) and determine the differences in the whole-blood cannabinoid profiles during symptomatic versus asymptomatic periods of participants with suspected cannabinoid hyperemesis syndrome recruited from the emergency department (ED) during a symptomatic episode.

METHODS

This is a prospective observational cohort study of participants with symptomatic cyclic vomiting onset after chronic cannabis use. Standardized assessments were conducted to evaluate for lifetime and recent cannabis use, cannabis use disorder, and cannabis withdrawal symptoms. Quantitative whole-blood cannabinoid testing was performed at 2 times, first when symptomatic (ie, baseline) and at least 2 weeks after the ED visit when asymptomatic. The differences in cannabinoid concentrations were compared between symptomatic and asymptomatic testing. The study was conducted from September 2021 to August 2022.

RESULTS

There was a difference observed between delta-9-tetrahydrocannabinol metabolites, but not the parent compound during symptomatic episodes and asymptomatic periods. Most participants (84%) reported using cannabis > once per day (median 3 times per day on weekdays, 4 times per day on weekends). Hazardous cannabis use was universal among participants; the mean cannabis withdrawal discomfort score was 13, indicating clinically significant rates of cannabis withdrawal symptoms with cessation of use. Most participants (79%) previously tried to stop cannabis use, but a few (13%) of them had sought treatment.

CONCLUSION

Patients presenting to the ED with cannabinoid hyperemesis syndrome have high cannabis use disorder scores. Further studies are needed to better understand the influence of THC metabolism and concentrations on symptomatic cyclic vomiting.

Cyclic Vomiting Syndrome and Cannabis Hyperemesis Syndrome: The State of the Science

This article provides a narrative review of the state of the science for both cyclic vomiting syndrome and cannabis hyperemesis syndrome along with a discussion of the relationship between these 2 conditions. The scope of this review includes the historical context of these conditions as well as the prevalence, diagnostic criteria, pathogenesis, and treatment strategies for both conditions. A synopsis of the endocannabinoid system provides a basis for the hypothesis that a lack of cannabidiol in modern high-potency Δ 9 -tetrahydrocannabinol cannabis may be contributory to cannabis hyperemesis syndrome and possibly other cannabis use disorders. In concluding assessment, though the publications addressing both adult cyclic vomiting syndrome and cannabis hyperemesis syndrome are steadily increasing overall, the state of the science supporting the treatments, prognosis, etiology, and confounding factors (including cannabis use) is of moderate quality. Much of the literature portrays these conditions separately and as such sometimes fails to account for the confounding of adult cyclic vomiting syndrome with cannabis hyperemesis syndrome. The diagnostic and therapeutic approaches are, at present, based generally on case series publications and expert opinion, with a very limited number of randomized controlled trials and a complete absence of Level 1 evidence within the cyclic vomiting literature overall as well as for cannabis hyperemesis syndrome specifically.

Clinical characteristics and long-term outcomes in patients with cyclic vomiting syndrome: A 15-year experience at a tertiary referral center

BACKGROUND

Cyclic vomiting syndrome (CVS) is a disorder of gut-brain interaction (DGBI) characterized by recurrent episodes of nausea and vomiting. Most children outgrow their CVS symptoms and develop migraine headaches, but there are limited data in adults. We thus sought to determine the natural history of CVS in adults.

METHODS

We conducted a retrospective analysis of patients at a specialized tertiary care clinic. Frequency of CVS episodes, emergency department (ED) visits, and hospitalizations were recorded at the index visit and at follow-up.

KEY RESULTS

Of 455 CVS patients with complete data, mean age was 33 ± 13 years, 294 (65%) were female, and 392 (86%) were Caucasian. Mean duration of follow-up was 47.4 ± 37.2 months. There was a significant reduction in frequency of CVS episodes/year (18 to 6.8), ED visits (6.1 to 2), and hospitalizations (2.3 to 0.7) (all p-values < 0.001) but only 88 (19%) of patients had complete resolution of episodes at follow-up. On multivariable regression analysis, non-white race [0.33 (0.11-0.98) p = 0.01], comorbidity count [0.77 (0.62-0.95) p = 0.01], cannabis use [0.36 (0.2-0.65) p = 0.0007], and aprepitant use [0.2 (0.08-0.005) p < 0.001] were associated with a reduced odds of complete resolution of CVS episodes. Of note, 19 patients (4%) died.

CONCLUSIONS AND INFERENCES

While most adults with CVS improved with specialized care, in contrast to children, only a small subset (~1 in 5) had complete resolution of symptoms. Reasons for the effects of race, cannabis use, and comorbidity burden on outcomes in CVS are unclear and warrant further investigation.

Diagnosis and Management of Cyclic Vomiting Syndrome: A Critical Review

Cyclic vomiting syndrome (CVS) is a chronic disorder of gut-brain interaction characterized by recurrent disabling episodes of nausea, vomiting, and abdominal pain. CVS affects both children and adults with a prevalence of approximately 2% in the United States. CVS is more common in female individuals and affects all races. The pathophysiology of CVS is unknown and a combination of genetic, environmental, autonomic, and neurohormonal factors is believed to play a role. CVS is also closely associated with migraine headaches and likely have a shared pathophysiology. The diagnosis of CVS is based on the Rome criteria, and minimal recommended testing includes an upper endoscopy and imaging studies of the abdomen. CVS is frequently associated with anxiety, depression, and autonomic dysfunction. Patients with CVS commonly use cannabis therapeutically for symptom relief. By contrast, cannabinoid hyperemesis syndrome is believed to be a subset of CVS with chronic heavy cannabis use leading to hyperemesis. Due to the recalcitrant nature of the illness, patients often visit the emergency department and are hospitalized for acute CVS flares. Guidelines on the management of CVS recommend a biopsychosocial approach. Prophylactic therapy consists of tricyclic antidepressants (amitriptyline), antiepileptics (topiramate), and aprepitant in refractory patients. Abortive therapy consists of triptans, antiemetics (ondansetron), and sedation. Treatment of comorbid conditions is extremely important to improve overall patient outcomes. CVS has a significant negative impact on patients, families, and the healthcare system, and future research to understand its pathophysiology and develop targeted therapies is needed.

Low patient engagement is associated with reduced health-related quality of life in adults with cyclic vomiting syndrome

INTRODUCTION

Patient engagement, adaptation and self-management play a critical role in improving Health Related Quality of Life (HRQOL) and reducing health care utilization in chronic disorders. There is no data on the level of patient engagement in patients with cyclic vomiting syndrome (CVS); we thus sought to determine their level of engagement and its association with clinical covariates.

METHODS

The Patient Activation Measure (PAM-13), a validated tool that measures the degree of patient engagement in their health was administered prospectively to patients with CVS. Data on demographics, health care utilization, and HRQOL (using the NIH PROMIS 10) were obtained. Patients were stratified into low engagement (PAM 1 & 2) and high engagement (PAM 3 & 4). The Fisher's exact test and Wilcoxon rank-sum tests were used to identifying significant differences between the groups.

RESULTS

Of 96 patients, 45% of patients had low levels of patient engagement. On multivariate analysis, low patient engagement was significantly associated with an increased number of CVS hospitalizations in the past year (aOR 1.26 [1.07, 1.54] p = .010), lower mental HRQOL scores (aOR 0.88 [0.78, 0.97] p = .022), current tobacco use (aOR 4.85 [1.24, 22.74] p = .031), and patients who were newly established in a specialized CVS clinic (aOR 44.40 [5.38, 70.02] p = .002).

CONCLUSION

Almost half of CVS patients demonstrate poor patient engagement, which is associated with poor outcomes. Identifying these patients and treatment in a specialized CVS center can potentially improve HRQOL, reduce health care utilization and improve overall healthcare outcomes.

Pharmacology, Clinical Effects, and Therapeutic Potential of Cannabinoids for Gastrointestinal and Liver Diseases

Cannabis and cannabinoids (such as tetrahydrocannabinol and cannabidiol) are frequently used to relieve gastrointestinal symptoms. Cannabinoids have effects on the immune system and inflammatory responses, as well as neuromuscular and sensory functions of digestive organs, including pancreas and liver. Cannabinoids can cause hyperemesis and cyclic vomiting syndrome, but they might also be used to reduce gastrointestinal, pancreatic, or hepatic inflammation, as well as to treat motility, pain, and functional disorders. Cannabinoids activate cannabinoid receptors, which inhibit release of transmitters from presynaptic neurons and also inhibit diacylglycerol lipase alpha, to prevent synthesis of the endocannabinoid 2-arachidonoyl glycerol. However, randomized trials are needed to clarify their effects in patients; these compounds can have adverse effects on the central nervous system (such as somnolence and psychosis) or the developing fetus, when used for nausea and vomiting during pregnancy. Cannabinoid-based therapies can also hide symptoms and disease processes, such as in patients with inflammatory bowel diseases. It is important for gastroenterologists and hepatologists to understand cannabinoid mechanisms, effects, and risks.

Cyclic Vomiting Syndrome in Children

Cyclic Vomiting Syndrome (CVS) is an underdiagnosed episodic syndrome characterized by frequent hospitalizations, multiple comorbidities, and poor quality of life. It is often misdiagnosed due to the unappreciated pattern of recurrence and lack of confirmatory testing. CVS mainly occurs in pre-school or early school-age, but infants and elderly onset have been also described. The etiopathogenesis is largely unknown, but it is likely to be multifactorial. Recent evidence suggests that aberrant brain-gut pathways, mitochondrial enzymopathies, gastrointestinal motility disorders, calcium channel abnormalities, and hyperactivity of the hypothalamic-pituitary-adrenal axis in response to a triggering environmental stimulus are involved. CVS is characterized by acute, stereotyped and recurrent episodes of intense nausea and incoercible vomiting with predictable periodicity and return to baseline health between episodes. A distinction with other differential diagnoses is a challenge for clinicians. Although extensive and invasive investigations should be avoided, baseline testing toward identifying organic causes is recommended in all children with CVS. The management of CVS requires an individually tailored therapy. Management of acute phase is mainly based on supportive and symptomatic care. Early intervention with abortive agents during the brief prodromal phase can be used to attempt to terminate the attack. During the interictal period, non-pharmacologic measures as lifestyle changes and the use of reassurance and anticipatory guidance seem to be effective as a preventive treatment. The indication for prophylactic pharmacotherapy depends on attack intensity and severity, the impairment of the QoL and if attack treatments are ineffective or cause side effects. When children remain refractory to acute or prophylactic treatment, or the episode differs from previous ones, the clinician should consider the possibility of an underlying disease and further mono- or combination therapy and psychotherapy can be guided by accompanying comorbidities and specific sub-phenotype. This review was developed by a joint task force of the Italian Society of Pediatric Gastroenterology Hepatology and Nutrition (SIGENP) and Italian Society of Pediatric Neurology (SINP) to identify relevant current issues and to propose future research directions on pediatric CVS.