Marijuana use does not affect weight loss or complication rate after bariatric surgery

American Society for Metabolic and Bariatric Surgery: postoperative care pathway guidelines for Roux-en-Y gastric bypass

BACKGROUND

Clinical care pathways and guidelines help guide and provide structure to clinicians and providers to improve healthcare delivery and quality. The Quality Improvement and Patient Safety (QIPS) Committee of the American Society for Metabolic and Bariatric Surgery (ASMBS) has previously published care pathways for the performance of laparoscopic sleeve gastrectomy (LSG), preoperative care of patients undergoing Roux-en-Y gastric bypass (RYGB), and most recently, intraoperative care of patients undergoing RYGB.

OBJECTIVES

This current RYGB care pathway guideline was created to address postoperative care guidance.

SETTING

Academic Health Center.

METHODS

For this systematic review, PubMed queries were performed from January 1979 to December 2019. Follow-up queries were performed from January 2020 to July 2024. Peer-reviewed publications were reviewed according to the level of evidence (LoE) regarding specific key questions developed by the QIPS Committee and working group for this pathway.

RESULTS

Evidence-based recommendations are made for the postoperative care of patients undergoing RYGB, including recommendations for early postoperative care, postoperative medication management, and long-term postoperative surveillance.

CONCLUSIONS

This document may provide a structure to providers based on current evidence for the postoperative care of patients with overweight or obesity undergoing RYGB.

Cannabis use before and after metabolic and bariatric surgery: literature review

As accessibility and legalization of cannabis rise throughout the United States (US), programs have sought guidance about whether its use should be considered a contraindication or, if not a contraindication, what recommendations patients should receive regarding appropriate use before and after metabolic and bariatric surgery (MBS). In this review, medical, nutritional, pharmacological, and psychological considerations are presented by a multidisciplinary group of members of the American Society for Metabolic and Bariatric Surgery (ASMBS). Research suggests several risks associated with long-term cannabis use in the general population, but research in the MBS population, specifically, is limited. Cannabis use is not associated with most postoperative complications but is associated with mental health concerns and disordered eating in patients who have undergone MBS. Research regarding weight loss outcomes is mixed, with most studies showing no significant association. Severe cannabis use appears to have more clinical significance than mild to moderate use, as it is associated with longer lengths of stay and medical complications. While an active cannabis use disorder is considered a contraindication, requiring treatment and abstinence before proceeding with surgery, the state of the literature is not strong enough to suggest that occasional or medical cannabis use is an absolute contraindication to MBS. Decisions about cannabis protocols should be made at the MBS program level, and patients should be fully informed about the risks of ongoing use.

Perioperative Cannabis Use in Bariatric Patients: A Review of Outcomes and Proposed Clinical Pathway for Management

Legalization of marijuana has led to increased prevalence of medical and recreational cannabis use, underscoring the importance for anesthesiologists, surgeons, and perioperative physicians to understand the effects of this drug in patient care. Bariatric surgical patients represent a unique target population to understand peri-operative cannabis use and its effects as these patients undergo an extensive preoperative psychological and nutritional evaluation. Standardized guidelines on cannabis use in bariatric surgery are lacking and many clinicians remain uncertain on how to handle cannabis use in the peri-operative period. Here, we summarize the data on cannabis use in bariatric patients, specifically exploring anesthetic considerations, weight loss, complications, mortality, and psychiatric outcomes. We propose a clinical pathway to assist clinicians with perioperative decision making in bariatric patients who use marijuana.

Cannabis smoking and abdominal wall reconstruction outcomes: a propensity score-matched analysis

PURPOSE

Despite increasing use of cannabis, literature on perioperative effects is lagging. We compared active cannabis-smokers versus non-smokers and postoperative wound morbidity and reoperations following open abdominal wall reconstruction (AWR).

METHODS

Patients who underwent open, clean, AWR with transversus abdominis release and retromuscular synthetic mesh placement at our institution between January 2014 and May 2022 were identified using the Abdominal Core Health Quality Collaborative database. Active cannabis-smokers were 1:3 propensity matched to non-smokers based on demographics and comorbidities. Wound complications, 30 day morbidity, pain (PROMIS 3a-Pain Intensity), and hernia-specific quality of life (HerQles) were compared.

RESULTS

Seventy-two cannabis-smokers were matched to 216 non-smokers. SSO (18% vs 17% p = 0.86), SSI (11.1% vs 9.3%, p = 0.65), SSOPI (12% vs 12%, p = 0.92), and all postoperative complications (46% vs 43%, p = 0.63) were similar between cannabis-smokers and non-smokers. Reoperations were more common in the cannabis-smoker group (8.3% vs 2.8%, p = 0.041), driven by major wound complications (6.9% vs 3.2%, p = 0.004). No mesh excisions occurred. HerQles scores were similar at baseline (22 [11, 41] vs 35 [14, 55], p = 0.06), and were worse for cannabis-smokers compared to non-smokers at 30 days (30 [12, 50] vs 38 [20, 67], p = 0.032), but not significantly different at 1 year postoperatively (72 [53, 90] vs 78 [57, 92], p = 0.39). Pain scores were worse for cannabis-smokers compared to non-smokers at 30 days postoperatively (52 [46, 58] vs 49 [44, 54], p = 0.01), but there were no differences at 6 months or 1 year postoperatively (p > 0.05 for all).

CONCLUSION

Cannabis smokers will likely experience similar complication rates after clean, open AWR, but should be counseled that despite similar wound complication rates, the severity of their wound complications may be greater than non-smokers.

Cannabis use following bariatric surgery is associated with anxiety and maladaptive eating

BACKGROUND

There are limited data regarding the association of cannabis use with outcomes after bariatric surgery. As such, it is challenging to know how to counsel patients using cannabis.

OBJECTIVES

The purpose of this study was to examine whether postsurgical cannabis use was associated with psychiatric symptoms and maladaptive eating among individuals up to 4 years after bariatric surgery.

SETTING

Single health system.

METHODS

All patients who underwent bariatric surgery over a 4-year period were invited to participate. Participants (N = 765) completed questionnaires online regarding postsurgical cannabis use, psychiatric symptoms, and maladaptive eating.

RESULTS

Any cannabis use after bariatric surgery was associated with increased likelihood of having elevated symptoms of anxiety (odds ratio [OR] = 1.88, P = .003; 37.8% versus 24.4%), increased likelihood of grazing behaviors (OR = 1.77, P = .01; 71.2% versus 58.2%), and higher scores for eating in response to depression (P = .01; 12.13 versus 10.75). Weekly cannabis use was associated with loss of control eating (OR = 1.81, P = .04; 37.2% versus 24.7%), binge eating (OR = 2.16, P = .03; 20.0% versus 10.4%), and night eating behaviors (OR = 2.11, P = .01; 40.0% versus 24.0%). Cannabis use was not associated with depression (P > .05).

CONCLUSIONS

Cannabis use after bariatric surgery was associated with anxiety symptoms and engaging in maladaptive eating behaviors. Frequent cannabis use (i.e., ≥1 per week) was associated with additional types of maladaptive eating. Clinicians involved in presurgical and postsurgical care may want to counsel patients currently using cannabis, especially those who are engaging in frequent use.

Post-surgical cannabis use is associated with weight loss among individuals up to 4 years after bariatric surgery

INTRODUCTION

Although cannabis is known to stimulate appetite, it is not clear whether cannabis use may impact weight loss outcomes following bariatric surgery. Although some work has suggested that pre-surgical cannabis use is not associated with post-surgical weight loss, the role of post-surgical cannabis use has not yet been examined. The purpose of this study was to measure pre- and post-surgical cannabis use and determine whether cannabis use was associated with weight loss outcomes following bariatric surgery.

METHODS

Patients who underwent bariatric surgery over a 4-year period at a single health care system were invited to complete a survey regarding pre- and post-surgical cannabis use and report their current weight. Pre-surgical weight and BMI were extracted from medical records to calculate change in BMI (ΔBMI), percent total weight loss (%TWL), percent excess weight loss (%EWL), whether participants experienced a successful weight loss outcome, and whether participants had weight recurrence.

RESULTS

Among all participants (N = 759), 10.7% and 14.5% engaged in pre- and post-surgical cannabis use, respectively. Pre-surgical cannabis use was not associated with any weight loss outcomes (p > 0.05). Any post-surgical cannabis use was associated with lower %EWL (p = 0.04) and greater likelihood of weight recurrence (p = 0.04). Weekly cannabis use was associated with lower %EWL (p = 0.003), lower %TWL (p = 0.04), and a lower likelihood of having a successful weight loss outcome (p = 0.02).

CONCLUSIONS

Although pre-surgical cannabis use may not predict weight loss outcomes, post-surgical cannabis was associated with poorer weight loss outcomes. Frequent use (i.e., weekly) may be especially problematic. Providers should consider screening patients for cannabis use and educate them about the potential impact of postoperative cannabis use on weight loss following bariatric surgery.

Severe Cannabis use is Associated with Complications and Prolonged Length of Stay in Bariatric Surgery

PURPOSE

In the United States, recreational and medicinal cannabis use has continually increased in recent years, including in patients undergoing bariatric surgery. However, the effects of cannabis use on morbidity and mortality after bariatric surgery are uncertain, and the literature is limited by a paucity of studies. This study intends to evaluate the effects of cannabis use disorder on outcomes in patients undergoing bariatric surgery.

MATERIALS AND METHODS

The National Inpatient Sample 2016-2019 was queried for patients ≥ 18 years who underwent roux-en-y gastric bypass (RYGB), vertical sleeve gastrectomy (VSG), or adjustable gastric band (AGB) surgery. Cannabis use disorder was identified using ICD-10 coding. Three outcomes were evaluated: medical complications, in-hospital mortality, and length of stay. Logistic regression was used to evaluate effects of cannabis use disorder on medical complications and in-hospital mortality, and linear regression for length of stay. All models controlled for race, age, sex, income, procedure type, and various medical comorbidities.

RESULTS

A total of 713,290 patients were included in this study, with 1,870 (0.26%) having cannabis use disorder. Cannabis use disorder was associated with medical complications (OR: 2.24; 95% CI: 1.31-3.82; P = 0.003) and longer lengths of stay (β: 1.3; SE: 0.297; P < 0.001), but not in-hospital mortality (OR: 3.29; CI: 0.94-11.5); P = 0.062).

CONCLUSIONS

Severe cannabis use was associated with higher risk for complications and extended length of stay. Future investigations are needed to better elucidate the relationship between cannabis use and bariatric surgery, including effects of dosage, chronicity, and method of ingestion.

The role of preoperative toxicology screening in patients undergoing bariatric surgery

BACKGROUND

Some programs and insurers may require patients to undergo toxicology screening despite lack of evidence that this practice affects postoperative outcomes.

OBJECTIVES

To understand the prevalence of screening positive on toxicology testing in the bariatric surgical population and to examine the association between testing positive and important surgical outcomes.

METHODS

We performed a retrospective review of patients who underwent laparoscopic sleeve gastrectomy or Roux-en-Y gastric bypass from an academic health system from 2017-2020. We described the rate of preoperative toxicology positivity as determined by serum and urine testing. We examined the association between toxicology positivity and outcomes of preoperative length, 30-day complications (bleeding, venous thromboembolism, leak, wound infection, pneumonia, urinary tract infection, and myocardial infarction), readmissions, and 1-year weight loss using chi-square and t-test analysis.

RESULTS

Of 1057 patients, there were 134 patients (12.7%) who had positive toxicology testing. Of these, 37 (28%) were positive for opiates and 21 (16%) were positive for cotinine. Mean preoperative length was 381.8 days (standard deviation [SD], 222.5) for patients with positive testing versus 287.8 days (SD, 151.5; P = 1.00) for negative testing. Toxicology positivity was not associated with readmissions (5.2% versus 4.3%, X² = 0.22; P = .64). The loss to follow-up at 1 year was 32.5%. There was no association with 1-year mean change in body mass index (mean of loss 12.23kg/m² [SD, 5.61]) versus mean of loss 12.74 (SD, 6.44; P = .20)].

CONCLUSIONS

Our study is the first to describe preoperative toxicology positivity rates. We found no association between toxicology positivity and preoperative length, readmissions, or weight loss. Given its lack of impact on outcomes, toxicology testing prior to bariatric surgery may be an unnecessary burden on patients and healthcare, with regard to cost and wait times.

Weight loss outcomes are not compromised in bariatric patients using cannabis

BACKGROUND

The legalization of cannabis in several states has led to increased documented use in the population. Bariatric surgery patients are no exception with estimates of anywhere from 6 to 8%. Cannabis is known to be associated with increased appetite, mood disorders, hyperphagia, and rarely, hyperemesis, which can potentially affect post-surgical weight loss. We aim to study the differences in bariatric surgery outcomes between cannabis users and non-users.

METHODS

A retrospective review identified patients undergoing bariatric surgery. Patients were divided into two groups, cannabis users (CU) and non-cannabis users (non-CU). Cannabis users (defined as using at least once weekly) and a group of non-users were called to obtain additional information. Primary outcome was weight loss. Secondary outcomes included incidence of post-operative nausea and vomiting (PONV), length of stay (LOS), readmission, and need for additional intervention.

RESULTS

A cohort of 364 sleeve gastrectomy patients met inclusion criteria, 31 (8.5%) CU and 333 (91.5%) non-CU. There was no difference in EWL between CU and non-CU at 1 week, 1 month, 3 months, 6 months, 9 months, 1 year, and 2 years. However, the CU group trended towards greater EWL at 3 years (52.9% vs. 38.1%, p = 0.094) and at 5 years (49.8% vs. 32.7%, p = 0.068). There were no significant differences between CU and non-CU with respect to either incidence or severity of PONV at one year after surgery or longer follow-up.

CONCLUSION

Cannabis users did not experience inferior weight loss after bariatric surgery despite common assumptions that appetite stimulation can lead to suboptimal weight loss outcomes. Our findings add to other work challenging this dogma. Larger, long-term, multicenter studies are warranted.