Preadmission chronic opioid usage and its association with 90-day mortality in critically ill patients: a retrospective cohort study

Opioid use following cardio-thoracic intensive care: risk factors and outcomes: a cohort study

Opioid misuse has become a serious public health problem. Patients admitted to cardio-thoracic critical care are usually exposed to opioids, but the incidence and effects of chronic opioid use are not known. The primary objective was to describe opioid use after admission to a cardio-thoracic intensive care unit. Secondary objectives were to identify factors associated with chronic opioid usage and analyze risk of death. This cohort study included all cardio-thoracic ICU care episodes in Sweden between 2010 and 2018. Among the 34,200 patients included in the final study cohort, 4050 developed persistent opioid use after ICU care. Younger age, preadmission opioid use, female sex, presence of comorbidities and earlier year of ICU admission were all found to be associated with persistent opioid use. The adjusted hazard ratio for mortality between 6 and 18 months after admission among individuals with persistent opioid use was 2.2 (95% CI 1.8-2.6; P < 0.001). For opioid-naïve patients before ICU admission, new onset of chronic opioid usage was significant during the follow-up period of 24 months. Despite the absence of conclusive evidence supporting extended opioid treatment, the average opioid consumption remains notably elevated twelve months subsequent to cardio-thoracic ICU care.

Causal effects and immune cell mediators between prescription analgesic use and risk of infectious diseases: a Mendelian randomization study

Introduction

Clinical observations have found that prolonged use of analgesics increases the incidence of infection. However, the direct causal relationship between prescription analgesic use (PAU) and risk of infection (ROI) remains unclear.

Methods

This study used Mendelian randomization (MR) design to estimate the causal effect of PAU on ROI, as well as their mediating factors. Genetic data on prescription analgesics use and immune cells were obtained from published GWAS. Additionally, data on ROI were extracted from the FinnGen database. Two-sample MR analysis and multivariate MR (MVMR) analysis were performed using inverse variance weighting (IVW) to ascertain the causal association between PAU and ROI. Finally, 731 immune cell phenotypes were analyzed for their mediating role between analgesics and infection.

Results

Using two-sample MR, IVW modeling showed that genetically predicted opioid use was associated with increased risk of pulmonary infection (PI) (OR = 1.13, 95% CI: 1.05-1.21, p< 0.001) and upper respiratory infection (URI) (OR = 1.18, 95% CI: 1.08-1.30, p< 0.001); non-steroidal anti-inflammatory drugs (NSAIDs) were related to increased risk of skin and subcutaneous tissue infection (OR = 1.21, 95% CI: 1.05-1.39, p = 0.007), and antimigraine preparations were linked to a reduced risk of virus hepatitis (OR = 0.79, 95% CI: 0.69-0.91, p< 0.001). In MVMR, the association of opioids with URI and PI remained after accounting for cancer conditions. Even with a stricter threshold (p< 0.05/30), we found a significant causal association between opioids and respiratory infections (URI/PI). Finally, mediation analyses found that analgesics influence the ROI through different phenotypes of immune cells as mediators.

Conclusion

This MR study provides new genetic evidence for the causal relationship between PAU and ROI, and the mediating role of immune cells was demonstrated.

Association between Substance Misuse and Outcomes in Critically III Patients with Pneumonia

Rationale: In patients with pneumonia requiring intensive care unit (ICU) admission, alcohol misuse is associated with increased mortality, but the relationship between other commonly misused substances and mortality is unknown. Objectives: We sought to establish whether alcohol misuse, cannabis misuse, opioid misuse, stimulant misuse, or misuse of more than one of these substances was associated with differences in mortality among ICU patients with pneumonia. Methods: This was a retrospective cohort study of hospitals participating in the Premier Healthcare Database between 2010 and 2017. Patients were included if they had a primary or secondary diagnosis of pneumonia and received antibiotics or antivirals within 1 day of admission. Substance misuse related to alcohol, cannabis, stimulants, and opioids, or more than one substance, were identified from the International Classification of Diseases (Ninth and Tenth Editions). The associations between substance misuse and in-hospital mortality were the primary outcomes of interest. Secondary outcomes included the measured associations between substance misuse disorders and mechanical ventilation, as well as vasopressor and continuous paralytic administration. Analyses were conducted with multivariable mixed-effects logistic regression modeling adjusting for age, comorbidities, and hospital characteristics. Results: A total of 167,095 ICU patients met inclusion criteria for pneumonia. Misuse of alcohol was present in 5.0%, cannabis misuse in 0.6%, opioid misuse in 1.5%, stimulant misuse in 0.6%, and misuse of more than one substance in 1.2%. No evidence of substance misuse was found in 91.1% of patients. In unadjusted analyses, alcohol misuse was associated with increased in-hospital mortality (odds ratio [OR], 1.12; 95% confidence interval [CI], 1.06-1.19), whereas opioid misuse was associated with decreased in-hospital mortality (OR, 0.46; 95% CI, 0.39-0.53) compared with no substance misuse. These findings persisted in adjusted analyses. Although cannabis, stimulant, and more than one substance misuse (a majority of which were alcohol in combination with another substance) were associated with lower odds for in-hospital mortality in unadjusted analyses, these relationships were not consistently present after adjustment. Conclusions: In this study of ICU patients hospitalized with severe pneumonia, substance misuse subtypes were associated with different effects on mortality. Although administrative data can provide epidemiologic insight regarding substance misuse and pneumonia outcomes, biases inherent to these data should be considered when interpreting results.

Reductions in All-Cause Mortality Associated with the Use of Methylnaltrexone for Opioid-Induced Bowel Disorders: A Pooled Analysis

OBJECTIVE

Preclinical and clinical studies suggest that activation of the µ-opioid receptor may reduce overall survival and increase the risk for all-cause mortality in patients with cancer and noncancer pain. Methylnaltrexone, a selective, peripherally acting µ-opioid receptor antagonist, has demonstrated efficacy for the treatment of opioid-induced constipation. This retrospective analysis of 12 randomized, double-blind, placebo-controlled studies of methylnaltrexone evaluated the treatment of opioid-induced bowel disorders in patients with advanced illness or noncancer pain.

METHODS

The risk of all-cause mortality within 30 days after the last dose of study medication during the double-blind phase was compared between methylnaltrexone and placebo groups. The data were further stratified by cancer vs noncancer, age, gender, and acute vs chronic diagnoses.

RESULTS

Pooled data included 2,526 methylnaltrexone-treated patients of which 33 died, and 1,192 placebo-treated patients of which 35 died. The mortality rate was 17.8 deaths/100 person-years of exposure in the methylnaltrexone group and 49.5 deaths/100 person-years of exposure for the placebo group. The all-cause mortality risk was significantly lower among patients receiving methylnaltrexone compared with placebo (hazard ratio: 0.399, 95% confidence interval: 0.25, 0.64; P = .0002), corresponding to a 60% risk reduction. Significant risk reductions were observed for those receiving methylnaltrexone who had cancer or chronic diagnoses. Methylnaltrexone-treated patients had a significantly reduced mortality risk compared with placebo regardless of age or gender.

CONCLUSIONS

Methylnaltrexone reduced all-cause mortality vs placebo treatment across multiple trials, suggesting methylnaltrexone may confer survival benefits in patients with opioid-induced bowel disorders taking opioids for cancer-related or chronic noncancer pain.

Immunomodulatory effects of pharmaceutical opioids and antipyretic analgesics: Mechanisms and relevance to infection

Understanding how pharmaceutical opioids and antipyretic analgesics interact with the immune system potentially has major clinical implications for management of patients with infectious diseases and surgical and critical care patients. An electronic search was carried out on MEDLINE, EMBASE, PsycINFO, CENTRAL and the Cochrane library to identify reports describing the immunomodulatory effects of opioid analgesics and antipyretic analgesics, and their effects in infectious diseases. In adaptive immunity, nonsteroidal anti-inflammatory drugs have divergent effects: augmenting cell-mediated immunity but inhibiting humoral immunity. Nonsteroidal anti-inflammatory drugs have demonstrated a beneficial role in Mycobacterium tuberculosis infection and histoplasmosis in animals, and may be plausible adjuvants to antimicrobial agents in these diseases. There is a need to evaluate these findings rigorously in human clinical trials. There is preliminary evidence demonstrating antiviral effects of indomethacin in SARS CoV-2 in vitro; however, uncertainty regarding its clinical benefit in humans needs to be resolved in large clinical trials. Certain opioid analgesics are associated with immunosuppressive effects, with a developing understanding that fentanyl, morphine, methadone and buprenorphine suppress innate immunity, whilst having diverse effects on adaptive immunity. Morphine suppresses key cells of the innate immunity and is associated with greater risk of infection in the postsurgical setting. Efforts are needed to achieve adequate analgesia whilst avoiding suppression of the innate immunity in the immediate postoperative period caused by certain opioids, particularly in cancer surgery.

Opioid Use After Intensive Care: A Nationwide Cohort Study

OBJECTIVE

To describe opioid use after ICU admission, identify factors associated with chronic opioid use after critical care, and determine if chronic opioid use is associated with an increased risk of death.

DESIGN

Retrospective cohort study.

SETTING

Sweden including all registered ICU admissions between 2010 and 2018.

PATIENTS

Adults surviving the first two quarters after ICU admission were eligible for inclusion. A total of 265,496 patients were screened and 61,094 were ineligible.

INTERVENTIONS

Admission to intensive care.

MEASUREMENTS AND MAIN RESULTS

Among 204,402 individuals included in the cohort, 22,138 developed chronic opioid use following critical care. Mean opioid consumption peaked after admission followed by a continuous decline without returning to baseline during follow-up of 24 months. Factors associated with chronic opioid use included high age, female sex, presence of comorbidities, preadmission opioid use, and ICU length of stay greater than 2 days. Adjusted hazard ratio for death 6-18 months after admission for chronic opioid users was 1.7 (95% CI, 1.6-1.7; p < 0.001). In the subset of patients not using opioids prior to admission, similar findings were noted.

CONCLUSIONS

Mean opioid consumption is increased 24 months after ICU admission despite the lack of evidence for long-term opioid treatment. Given the high number of ICU entries and risk of excess mortality for chronic users, preventing opioid misuse is important when improving long-term outcomes after critical care.

The immunomodulatory effects of opioids and implications for intensive care unit populations

Analgesia within the intensive care unit (ICU) is often achieved via the utilization of opioids in alignment with current guidelines. Recent evidence has not only demonstrated the potential impact of opioids in suppression of immune function, but also the potential harm of immunosuppression of patients within the ICU. Despite the potential immunosuppression seen with opioids in this at-risk population, their use remains frequent. In this review, we highlight the potential immunomodulatory impact of opioids within the critically ill and considerations for their use.

Frailty modifies the association between opioid use and mortality in chronic kidney disease patients with diabetes: a population-based cohort study

The prevalence of chronic pain in patients with chronic kidney disease (CKD) and diabetes mellitus is high and correlates with higher frailty risk, but satisfactory pain control frequently fails, necessitating opioid initiation. We aimed to examine whether opioid use affected their outcomes and whether such a relationship was modified by frailty. From the longitudinal cohort of diabetes patients (n = 840,000), we identified opioid users with CKD (n = 26,029) and propensity score-matched them to opioid-naïve patients in a 1:1 ratio. We analyzed the associations between opioid use and long-term mortality according to baseline frailty status, defined by the modified FRAIL scale. Among all, 20.3% did not have any FRAIL items, while 57.2%, 20.6%, and 1.9% had 1, 2, and at least 3 positive FRAIL items, respectively. After 4.2 years, 16.4% died. Cox proportional hazard regression showed that opioid users exhibited an 18% higher mortality risk (HR 1.183, 95% CI 1.13-1.24) with a dose- and duration-responsive relationship, compared to opioid-naive ones. Furthermore, the mortality risk posed by opioids was observed only in CKD patients without frailty but not in those with frailty. In conclusion, opioid use increased mortality among patients with CKD, while this negative outcome influence was not observed among frail ones.

Long-term opioid use among patients with chronic gout: a cross-sectional study of a sample cohort in South Korea

OBJECTIVES

This study aimed to determine trends in the prevalence of chronic opioid users among patients with chronic gout in South Korea from 2002 to 2015 and to investigate the factors associated with chronic opioid use among patients with chronic gout.

METHODS

We performed a population-based cohort study and extracted data from the National Health Insurance Service database in South Korea. We included all adult patients (age ≥ 18 years) with a diagnostic code of M1A* (chronic gout) according to the International Classification of Disease (10th revision).

RESULTS

The prevalence of chronic opioid users among patients with chronic gout has gradually increased from 4.0% in 2002 to 19.4% in 2015. After excluding the patients who had a history of cancer or other rheumatic diseases, a total of 18,042 patients with chronic gout were included in this cross-sectional cohort study in 2015, of which 993 (5.5%) were long-term opioid users. In a multivariable model, older age, female sex, Charlson Comorbidity Index > 2, long-term use of other analgesics, such as pregabalin, gabapentin, paracetamol, and glucocorticoids, and the use of other gout medication (colchicine) were independently associated with higher rates of long-term opioid use among patients with chronic gout.

CONCLUSION

Chronic opioid users among patients with chronic gout increased from 2002 to 2015 in South Korea. Female sex, older age, comorbid status, and the use of other non-opioid analgesics were independently associated with higher rates of long-term opioid use among patients with chronic gout. Key Points • Chronic opioid users among patients with chronic gout have increased from 2002 to 2015 in South Korea. • Among patients with chronic gout, 5.5% were long-term opioid users. • Female sex, older age, comorbid status, and the use of other non-opioid analgesics were associated with higher rates of long-term opioid use.

Trends in chronic opioid use and association with five-year survival in South Korea: a population-based cohort study

BACKGROUND

The Korean National Health Insurance Service (NHIS) was developed to provide population data for medical research. The aim of this study was to estimate trends in prescription opioid use in South Korea, and to determine the association between chronic opioid use and 5-yr mortality in cancer and non-cancer patients.

METHODS

A population-based cohort study was conducted amongst the South Korean adult population using data from the NHIS. Those prescribed a continuous supply of opioids for ≥90 days were defined as chronic opioid users. Multivariable Cox regression analysis was used to assess the association between chronic opioid use and 5-yr mortality.

RESULTS

The proportion of chronic weak opioid users increased from 1.03% in 2002 to 9.62% in 2015. The proportion of chronic strong opioid users increased from 0.04% in 2002 to 0.24% in 2015. In the 2010 cohort (n=822 214), compared with non-users, chronic weak opioid users had a significantly lower 5-yr mortality (hazard ratio [HR]: 0.93; 95% confidence interval [CI]: 0.89-0.96; P<0.001), and chronic strong opioid users had a significantly higher 5-yr mortality (HR: 1.45; 95% CI: 1.28-1.63; P<0.001). Similar results were observed in non-cancer patients, but chronic weak opioid users were not significantly associated with 5-yr mortality in cancer patients (P=0.063).

CONCLUSIONS

In South Korea, chronic opioid use has increased since 2002. Chronic strong opioid use was associated with a higher 5-yr mortality, and chronic weak opioid use was associated with a slightly lower 5-yr mortality. However, the findings regarding chronic weak opioid users should be interpreted carefully because there might be residual confounders in this study. Further study is needed to confirm these retrospective findings.