Long-term opioid use after bariatric surgery

The Effects of Bariatric Surgery on Pharmacokinetics of Drugs: a Review of Current Evidence

PURPOSE OF REVIEW

Obesity constitutes a major public health concern and has been recognized as an epidemic. To date, bariatric surgery remains the most effective way for substantial long-lasting weight loss in severe obesity. The purpose of this review is to summarize how the pharmacokinetics of drugs are affected by the most common types of bariatric surgery, i.e., Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG).

RECENT FINDINGS

Limited data are available regarding the changes in pharmacokinetics of drugs after bariatric surgery. The lack of existing guidelines may lead patients to experience drug toxicity or therapeutic undertreatment. Pharmacokinetic parameters that need to be taken into consideration postoperatively include gastric motility, gastric volume, pH, surface area, bile secretions, carrier proteins, and first-pass metabolism. For drugs with a narrow therapeutic index, other factors need to be monitored closely, including plasma drug levels, patients' clinical outcomes, and laboratory markers. Patients should be followed up frequently and treated in accordance with their response to the drug therapy. Bariatric surgery may affect the pharmacokinetics of various drugs, due to the resultant anatomical changes and the substantial weight loss. Therefore, there is a need to identify those potential changes and adjust patients' medication doses in order to achieve higher efficacy and avoid toxicity.

Impact of socioeconomic status on new chronic opioid use after gastric bypass surgery

BACKGROUND

Socioeconomic status may influence weight loss, postoperative complications, and health-related quality of life after bariatric surgery. Chronic use of opioid analgesics is a known risk after bariatric surgery, but whether socioeconomic factors are associated with new chronic use of opioid analgesics has not been investigated in depth.

OBJECTIVES

The aim of this study was to identify socioeconomic factors associated with the development of new chronic use of opioid analgesics after gastric bypass surgery.

SETTING

All hospitals performing bariatric surgery in Sweden.

METHODS

This was a retrospective cohort study with prospectively collected data including all primary gastric bypass procedures in Sweden between 2007 and 2015. Data were collected from the Scandinavian Obesity Surgery Registry, the Swedish Prescribed Drug Register, and Statistics Sweden. The primary outcome was new chronic opioid use.

RESULTS

Of the 44,671 participants, 1438 patients became new chronic opioid users. Longer education (secondary education; odds ratio [OR] = .71; 95% CI, .62-.81) or higher education (OR = .45; 95% CI, .38-.53), higher disposable income (20th-50th percentile: OR = .75; 95% CI, .66-.85; 50th-80th percentile: OR = .50; 95% CI, .43-.58; and the highest 80th percentile: OR = .40; 95% CI, .32-.51) were significantly associated with lower risk for new chronic opioid use. Being a second-generation immigrant (OR = 1.54; 95% CI, 1.24-1.90), being on a disability pension or early retirement (OR = 3.04; 95% CI, 2.67-3.45), receiving social benefits (OR = 1.88; 95% CI, 1.59-2.22), being unemployed for <100 days (OR = 1.25; 95% CI, 1.08-1.45), being unemployed for >100 days (OR = 1.41; 95% CI, 1.16-1.71), and being divorced or a widow or widower (OR = 1.35; 95% CI, 1.17-1.55) were significantly associated with a higher risk for chronic opioid use.

CONCLUSION

Given that long-term opioid use has detrimental effects after bariatric surgery, it is important that information and follow-up are optimized for patients with shorter education, lower income, and disability pension or early retirement because they are at an increased risk of new chronic opioid analgesics use.

Predictors of post-discharge pain and satisfaction with pain management after laparoscopic bariatric surgery: a prospective cohort study

BACKGROUND

Pain management after bariatric surgery remains challenging given the risk for analgesia-related adverse events (e.g., opioid use disorder, marginal ulcers). Identifying modifiable factors associated with patient-reported pain outcomes may improve quality of care. We evaluated the extent to which patient and procedural factors predict 7-day post-discharge pain intensity, pain interference, and satisfaction with pain management after bariatric surgery.

METHODS

This prospective cohort study included adults undergoing laparoscopic bariatric surgery at two university-affiliated hospitals and one private clinic. Preoperative assessments included demographics, Pain Catastrophizing Scale (score range 0-52), Patient Activation Measure (low [< 55.1] vs. high [≥ 55.1]), pain expectation (0-10), and Patient-Reported Outcomes Measurement Information System-29 (PROMIS-29) anxiety and depression scales. At 7 days post-discharge, assessments included PROMIS-29 pain intensity (0-10) and pain interference scales (41.6-75.6), and satisfaction with pain management (high [10-9] vs. lower [8-0]). Linear and logistic regression were used to assess the association of pain outcomes with potential predictors.

RESULTS

Three hundred and fifty-one patients were included (mean age = 44 ± 11 years, BMI = 45 ± 8 kg/m2, 77% female, 71% sleeve gastrectomy). At 7 days post-discharge, median (IQR) patient-reported pain intensity was 2.5 (1-5), pain interference was 55.6 (52.0-61.2), and 76% of patients reported high satisfaction with pain management. Pain intensity was predicted by preoperative anxiety (β + 0.04 [95% CI + 0.01 to + 0.07]) and pain expectation (+ 0.15 [+ 0.05 to + 0.25]). Pain interference was predicted by preoperative anxiety (+ 0.22 [+ 0.11 to + 0.33]), pain expectation (+ 0.47 [+ 0.10 to + 0.84]), and age (- 0.09 [- 0.174 to - 0.003]). Lower satisfaction was predicted by low patient activation (OR 1.94 [1.05-3.58]), higher pain catastrophizing (1.03 [1.003-1.05]), 30-day complications (3.27 [1.14-9.38]), and age (0.97 [0.948-0.998]).

CONCLUSION

Patient-related factors are important predictors of post-discharge pain outcomes after bariatric surgery. Our findings highlight the value of addressing educational, psychological, and coping strategies to improve postoperative pain outcomes.

Bariatric Surgery and Suicide Risk in Patients With Obesity

OBJECTIVE

In a large multisite cohort of Veterans who underwent Roux-en-Y gastric bypass or laparoscopic sleeve gastrectomy, we compared the 5-year suicidal ideation and attempt rates with matched nonsurgical controls.

BACKGROUND

Bariatric surgery has significant health benefits but has also been associated with adverse mental health outcomes.

METHODS

Five-year rates of suicidal ideation and suicide attempts of Veterans who underwent Roux-en-Y gastric bypass or laparoscopic sleeve gastrectomy from the fiscal year 2000-2016 to matched nonsurgical controls using sequential stratification using cumulative incidence functions (ideation cohort: n=38,199; attempt cohort: n=38,661 after excluding patients with past-year outcome events). Adjusted differences in suicidal ideation and suicide attempts were estimated using a Cox regression with a robust sandwich variance estimator.

RESULTS

In the matched cohorts for suicidal ideation analyses, the mean age was 53.47 years and the majority were males (78.7%) and White (77.7%). Over 40% were treated for depression (41.8%), had a nonrecent depression diagnosis (40.9%), and 4.1% had past suicidal ideation or suicide attempts >1 year before index. Characteristics of the suicide attempt cohort were similar. Regression results found that risk of suicidal ideation was significantly higher for surgical patients (adjusted hazard ratio=1.21, 95% CI: 1.03-1.41), as was risk of suicide attempt (adjusted hazard ratio=1.62, 95% CI: 1.22-2.15).

CONCLUSIONS

Bariatric surgery appears to be associated with a greater risk of suicidal ideation and attempts than nonsurgical treatment of patients with severe obesity, suggesting that patients need careful monitoring for suicidal ideation and additional psychological support after bariatric surgery.

Opioid Analgesics after Bariatric Surgery: A Scoping Review to Evaluate Physiological Risk Factors for Opioid-Related Harm

The persisting use of opioids following bariatric surgery has emerged as a prevalent complication, heightening the probability of opioid-related harm (ORM), such as opioid-related fatalities and prescription opioid use disorder (OUD). A comprehensive review of PubMed literature from 1990 to 2023 was conducted to pinpoint physiological influences on postoperative ORM. As a result, we found that patients undertaking bariatric operations often exhibit an inherently higher risk for substance use disorders, likely attributable to genetic predisposition and related neurobiological changes that engender obesity and addiction-like tendencies. Furthermore, chronic pain is a common post-bariatric surgery complaint, and the surgical type impacts opioid needs, with increased long-term opioid use after surgeries. Additionally, the subjective nature of pain perception in patients with obesity can distort pain reporting and the corresponding opioid prescription both before and after surgery. Furthermore, the postoperative alterations to the gastrointestinal structure can affect the microbiome and opioid absorption rates, resulting in fluctuating systemic exposure to orally ingested opioids. The prospect of ORM development post-bariatric surgery appears amplified due to a preexisting susceptibility to addictive habits, surgically induced pain, modified gut-brain interaction and pain management and the changed pharmacokinetics post-surgery. Further research is warranted to clarify these potential risk variables for ORM, specifically OUD, in the bariatric population.

Incidence of Substance Use Disorder Following Bariatric Surgery: A Retrospective Cohort Study

BACKGROUND

New-onset substance use disorder (SUD) following bariatric surgery is a significant concern that is likely multi-factorial, although the etiologies are unclear. Previous studies have identified variable rates of SUD along with utilizing different methods and measures. The objective of this study is to evaluate new-onset SUD diagnoses among adults following bariatric surgery and compare these rates to those in the general population as well as those diagnosed with overweight or obesity.

METHODS

Data was extracted from TriNetX Research Platform and used to build three cohorts of adults: those who had bariatric surgery (bariatric surgery cohort), those diagnosed with obesity or overweight, and a general population cohort. Rates of incident SUD were compared among these three groups. Initial encounters for all individuals were from January 1, 2018, to June 30, 2019.

RESULTS

The incidence rate of SUD in patients with a history of bariatric surgery was 6.55% (n = 2523). When compared to the general population, persons who had any type of bariatric procedure had a decreased risk of new-onset SUD with an overall odds ratio (OR) [95% confidence limits (CL)] of 0.89 [0.86, 0.93]. When compared to persons with overweight or obesity, bariatric patients were less likely to develop any form of SUD (OR: 0.65 [0.62, 0.67]).

CONCLUSION

While overall rates of new-onset SUD are lower among those who had bariatric surgery, they also vary by surgery and substance type. Efforts should still be made to address new-onset SUD in order to optimize the post-surgical care of patients.

Opioid Use After Gastric Bypass, Sleeve Gastrectomy or Intensive Lifestyle Intervention

OBJECTIVE

To compare opioid use in patients with obesity treated with bariatric surgery versus adults with obesity who underwent intensive lifestyle modification.

SUMMARY OF BACKGROUND DATA

Previous studies of opioid use after bariatric surgery have been limited by small sample sizes, short follow-up, and lack of control groups.

METHODS

Nationwide matched cohort study including individuals from the Scandinavian Obesity Surgery Registry and the Itrim health database with individuals undergoing structured intensive lifestyle modification, between August 1, 2007 and September 30, 2015. Participants were matched on Body Mass Index, age, sex, education, previous opioid use, diabetes, cardiovascular disease, and psychiatric status (n = 30,359:21,356). Dispensed opioids were retrieved from the Swedish Prescribed Drug Register from 2 years before to up to 8 years after intervention.

RESULTS

During the 2-year period before treatment, prevalence of individuals receiving ≥1 opioid prescription was identical in the surgery and lifestyle group. At 3 years, the prevalence of opioid prescriptions was 14.7% versus 8.9% in the surgery and lifestyle groups (mean difference 5.9%, 95% confidence interval 5.3-6.4) and at 8 years 16.9% versus 9.0% (7.9%, 6.8-9.0). The difference in mean daily dose also increased over time and was 3.55 mg in the surgery group versus 1.17 mg in the lifestyle group at 8 years (mean difference [adjusted for baseline dose] 2.30 mg, 95% confidence interval 1.61-2.98).

CONCLUSIONS

Bariatric surgery was associated with a higher proportion of opioid users and larger total opioid dose, compared to actively treated obese individuals. These trends were especially evident in patients who received additional surgery during follow-up.

Impact of Perioperative Ketamine on Postoperative Bariatric Surgery Opioid Use and Length of Stay

SETTINGS

Postoperative pain management is an ever-growing challenge with the rise of the opioid crisis. Ketamine is an NMDA channel blocker, considered an alternative to perioperative opioid use; small concentrations are safe. Objective: The primary objective of this study was to evaluate the impact of perioperative ketamine administration on postoperative opioid use and the length of hospital stay in bariatric patients.

METHODS

Four hundred (366) charts were retrospectively reviewed; of those, 187 received ketamine and were placed in the Ketamine group, 179 received standard-of-care pain management and were part of the No-Ketamine group. Data was collected using medical databases from July 2020 to January 2021.

RESULTS

A greater length of stay was recorded in the No-Ketamine group (45.67±20.6 hours) when compared with the Ketamine group (40.6±14.3 hours); P <0.05. The Ketamine group had a mean MME of 17.5±16.5 whereas the No-Ketamine had a mean MME of 22.3±17.7, P <0.05.

CONCLUSIONS

Ketamine may be a feasible alternative to reduce opioid use and hospital length of stay. We believe that ketamine can be an important contribution to ERABS pathways, being responsible for improved outcomes after bariatric/metabolic surgical procedures.

Factors that influence discharge opioid prescribing among bariatric surgeons across Michigan

BACKGROUND

Opioid prescribing following bariatric surgery has been a focus due to its association with new persistent opioid use (NPOU) and worse outcomes. Guidelines have led to a reduction in opioids prescribed, but there remains variation in prescribing practices.

METHODS

We conducted interviews with 20 bariatric surgeons across Michigan. Transcripts were analyzed using descriptive content analysis.

RESULTS

At the patient level, surgeons described the role of surgical history and pain tolerance. At the provider level, surgeons discussed patient dissatisfaction, reputation, and workload. At the institution level, surgeons discussed colleagues, resources, and administration. At a collaborative level, surgeons described the role of evidence and performance measures. There was lack of consensus on whether NPOU is a problem facing patients undergoing bariatric surgery.

CONCLUSION

Despite efforts aimed at addressing opioid prescribing, variability exists in prescribing practices. Understanding determinants that impact stakeholder alignment is critical to increasing adherence to guideline-concordant care.

The Effect of Bariatric Surgery on Long-term Depression Treatment in Patients With Obesity

OBJECTIVE

In a large multisite cohort of Veterans who underwent Roux-en-Y gastric bypass (RYGB) or laparoscopic sleeve gastrectomy (LSG), initiation of (ie, incident) and persistence of (ie, continuation of preoperative) depression treatment are compared with matched nonsurgical controls.

BACKGROUND

Bariatric surgery has been associated with short-term improvements in depression but less is known about longer term outcomes.

METHODS

In a retrospective cohort study, we matched 1713 Veterans with depression treatment who underwent bariatric surgery in Veterans Administration bariatric centers from fiscal year 2001 to 2016 to 15,056 nonsurgical controls using sequential stratification and examined the persistence of depression treatment via generalized estimating equations. Incidence of depression treatment was compared using Cox regression models between 2227 surgical patients and 20,939 matched nonsurgical controls without depression treatment at baseline.

RESULTS

In surgical patients with depression treatment at baseline, the use of postsurgical depression treatment declined over time for both surgical procedures, but postsurgical patients had greater use of depression treatment at 5 years [RYGB: odds ratio=1.24, 95% confidence interval (CI): 1.04-1.49; LSG: odds ratio=1.27, 95% CI: 1.04-1.56] compared with controls. Among those without depression treatment at baseline, bariatric surgery was associated with a higher incidence of depression treatment compared with matched controls (RYGB: hazard ratio=1.34, 95% CI: 1.17-1.53; LSG: hazard ratio at 1-5 years=1.27, 95% CI: 1.10-1.47).

CONCLUSIONS

Bariatric surgery was associated with a greater risk of postoperative incident depression treatment and greater persistence of postoperative depression treatment. Depression may worsen for some patients after bariatric surgery, so clinicians should carefully monitor their patients for depression postoperatively.

Outcomes of Bariatric Surgery in Patients on Chronic Opioids: Can Bariatric Surgery Assist with Decreasing Long-term Opioid Utilization?

PURPOSE

The aim of our study was to assess long-term opioid use following bariatric surgery in patients on preoperative narcotics.

METHODS

We evaluated patients utilizing preoperative opioids (OP) who underwent primary laparoscopic Roux-en-Y gastric bypass (LRYGB) from 2013 to 2020. Patients were propensity-matched to those without preoperative opioid use (NOP) by demographics and comorbidities. Our objectives were to compare opioid use at 1 and 3 years after surgery and evaluate perioperative outcomes.

RESULTS

A total of 806 patients, matched 1:1 were evaluated, with 82.7% being females. Mean age was 46.5 years in the OP and 45.6 years in the NOP (p = 0.0018), preoperative BMI was 45.8 in the OP and 46.1 in the NOP (p = 0.695). All patients were followed up for 1 year. In the OP, 156 (38.7%) patients were taking opioids 1 year after surgery as opposed to 27 (6.7%) in the NOP (p < 0.0001). Three years after surgery, 74 (37.5%) patients in the OP and 27 (14.4%) in the NOP were taking outpatient opioids (p < 0.0001). There was no statistically significant difference between OP and NOP groups in terms of readmissions (9.4% vs. 5.7% p = 0.06), reinterventions (3.7 vs. 1.7% p = 0.13), reoperations (3.5% vs. 1.5% p = 0.11), or emergency room visits (8.9% vs. 7.2% p = 0.44). There were no mortalities.

CONCLUSION

Most patients requiring preoperative opioids can be weaned off after bariatric surgery. Enhanced recovery pathways are key to obtaining these results. Preoperative opioid use is not associated with increased complications compared to opioid-naïve patients.

Hospital opioid use predicts the need for discharge opioid prescriptions following laparoscopic bariatric surgery

BACKGROUND

Overprescribing of opioids after surgery increases new persistent opioid use and diversion contributing to the opioid epidemic. There is a paucity of evidence regarding discharge opioid prescribing after bariatric surgery.

METHODS

We conducted a retrospective, cohort study analyzing post-operative opioid use at a single institution in patients who underwent laparoscopic sleeve gastrectomy (LSG) and laparoscopic Roux-en-Y gastric bypass (LGB) from July 2019 thru February 2020. Multimodal analgesia was used including 5 mg oxycodone pills as needed during hospitalization with five prescribed on discharge if requested after discussion. Opioid use was determined from medical record review and post-operative data collected from patients at a 2-week follow-up visit. The Michigan Automated Prescription System (MAPS) was used as an adjunct to evaluate perioperative opioid prescriptions.

RESULTS

The cohort of 84 patients included those having LSG (72) and LGB (12). Fifty-five patients (65%) received a prescription for opioids on discharge and 91% filled their prescription. Only 44% (22/50) of those filling their opioid prescription took any opioids with 24% (65/275) of the total pills prescribed actually consumed. Opioid use on the surgical ward had the strongest correlation with discharge opioid use (rho = 0.65, CI 0.494, 0.770). The number of opioid pills taken on the surgical ward was positively associated with the number of pills taken after discharge. Those who took none, 1 to 3, or 4 or more opioid pills consumed 0.14 ± 0.48, 0.95 ± 1.71, and 3.14 ± 1.86 pills after discharge (p < 0.001). No patients required an additional opioid prescription within 90 days of surgery with MAPS confirmation.

CONCLUSION

Postoperative in-hospital opioid use following laparoscopic bariatric surgery predicts opioid use after discharge. This knowledge can guide patient-specific discharge opioid prescribing with the potential to mitigate diversion and reduce chronic opioid use.

Association of prenatal substance use disorders with pregnancy and birth outcomes following bariatric surgery

BACKGROUND/OBJECTIVES

While an increased risk for substance use disorders (SUD) and also for several adverse pregnancy and birth outcomes in patients who have undergone bariatric surgery have been well documented when considered separately, an association between these important risk factors has not been investigated. This study explored the potential dependence of these two bariatric surgery-related risks.

SUBJECTS/METHODS

This study was a retrospective cohort study with adult women (18-45) who underwent bariatric surgery between 1996 and 2016 and who gave birth after surgery between 1996 and 2018. The study population consisted of 1849 post-bariatric surgery women with 3010 reported post-surgical births. Subjects with post-surgical, prenatal SUD were identified based on diagnosis codes extracted within the 10 months prior to delivery. Using random-effects logistic regression with retrospective cohort data, preterm birth, low birth weight, macrosomia, Caesarian delivery, congenital anomalies, and neonatal intensive care unit admission were considered as outcomes.

RESULTS

About 10% (n = 289) of women had an SUD diagnosis within 10 months prior to child delivery. Women with SUD during pregnancy had significantly more pregnancy and birth complications compared to women without SUD: preterm birth (OR = 2.08, p = 0.03, 95% CI: 1.07-4.03), low birth weight (OR = 3.41, p < 0.01, 95% CI: 1.99-5.84), Caesarian delivery (OR = 9.71, p < 0.01, 95% CI: 2.69-35.05), and neonatal intensive care unit admission (OR = 3.87, p < 0.01, 95% CI: 2.04-7.34). Women with SUD had lower risk for macrosomia than women without SUD (OR = 0.07, p = 0.02, 95% CI: 0.01-0.70).

CONCLUSION

Results from this study demonstrated that post-bariatric surgery women who had SUD during pregnancy had significantly more pregnancy- and birth-related complications than post-surgery pregnant women without SUD, despite the reduction in macrosomia. Where possible, greater prenatal surveillance of post-surgery women with SUD should be considered.

Addiction Transfer and Other Behavioral Changes Following Bariatric Surgery

Despite its important treatment implications for obesity and related comorbidities, bariatric surgery requires several behavioral changes that warrant comprehensive evaluation and support before and after surgery. This article outlines emerging scientific and anecdotal evidence for addiction transfer after bariatric surgery. Other common behavioral changes that impact adherence, weight loss, and psychiatric risk after surgery are also reviewed. Last, recommendations for presurgical psychological evaluation and postoperative support are provided.