A Subgroup Analysis Found no Diminished Response to Buprenorphine Transdermal System Treatment for Chronic Low Back Pain Patients Classified with Depression

Association Between Depressive Symptoms or Depression and Health Outcomes for Low Back Pain: a Systematic Review and Meta-analysis

BACKGROUND

Study results vary on whether depressive symptoms are associated with worse prognosis for low back pain (LBP). We assessed the association between depressive symptoms or depression and health outcomes in persons with LBP.

METHODS

We searched MEDLINE, Embase, CINAHL, and PsycINFO from inception to June 2020. Eligible studies were cohort and case-control studies assessing the association between depressive symptoms (questionnaires) or depression (diagnoses) and health outcomes in persons aged ≥16 years with LBP in the absence of major pathology. Reviewers independently screened articles, extracted data, and assessed risk of bias using the Quality in Prognosis Studies tool. We classified exploratory versus confirmatory studies based on phases of prognostic factor investigation. We conducted random-effects meta-analyses and descriptive synthesis where appropriate.

RESULTS

Of 13,221 citations screened, we included 62 studies (63,326 participants; 61 exploratory studies, 1 confirmatory study). For acute LBP, depressive symptoms were associated with self-reported disability (descriptive synthesis: 6 studies), worse recovery (descriptive synthesis: 5 studies), and slower traffic injury-related claim closure (1 study), but not pain or work-related outcomes. Depressive symptoms were associated with greater primary healthcare utilization for acute LBP (1 confirmatory study). For chronic LBP, depressive symptoms were associated with higher pain intensity (descriptive synthesis: 9 studies; meta-analysis: 3 studies, 2902 participants, β=0.11, 95% confidence interval (CI) 0.05-0.17), disability (descriptive synthesis: 6 studies; meta-analysis: 5 studies, 3549 participants, β=0.16, 95% CI 0.04-0.29), and worse recovery (descriptive synthesis: 2 studies; meta-analysis: 2 studies, 13,263 participants, relative risk (RR)=0.91, 95% CI 0.88-0.95), but not incident chronic widespread pain (1 study).

DISCUSSION

Depressive symptoms may be associated with self-reported disability and worse recovery in persons with acute and chronic LBP, and greater primary healthcare utilization for acute LBP. Our review provides high-quality prognostic factor information for LBP. Healthcare delivery that addresses depressive symptoms may improve disability and recovery in persons with LBP. Confirmatory studies are needed to assess the association between depressive symptoms and health outcomes in persons with LBP.

PROTOCOL REGISTRATION

PROSPERO database (CRD42019130047).

Efficacy and safety of strong opioids for chronic noncancer pain and chronic low back pain: a systematic review and meta-analyses

ABSTRACT

In recent years, long-term prescribing and use of strong opioids for chronic noncancer pain (CNCP) has increased in high-income countries. Yet existing uncertainties, controversies, and differing recommendations make the rationale for prolonged opioid use in CNCP unclear. This systematic review and meta-analyses compared the efficacy, safety, and tolerability of strong opioids with placebo or nonopioid therapy in CNCP, with a special focus on chronic low back pain (CLBP). Systematic literature searches were performed in 4 electronic databases (MEDLINE, Web of Science, Cochrane Library, and CINAHL) in July 2019 and updated by regular alerts until December 2020. We included 16 placebo-controlled randomized controlled trials for CLBP and 5 studies (2 randomized controlled trials and 3 nonrandomized studies) of opioids vs nonopioids for CNCP in the quantitative and qualitative synthesis. Random effects pairwise meta-analyses were performed for efficacy, safety, and tolerability outcomes and subgroup analyses for treatment duration, study design, and opioid experience status. Very low to low certainty findings suggest that 4 to 15 weeks (short or intermediate term) opioid therapy in CLBP (compared with placebo) may cause clinically relevant reductions in pain but also more gastrointestinal and nervous system adverse events, with likely no effect on disability. By contrast, long-term opioid therapy (≥6 months) in CNCP may not be superior to nonopioids in improving pain or disability or pain-related function but seems to be associated with more adverse events, opioid abuse or dependence, and possibly an increase in all-cause mortality. Our findings also underline the importance and need for well-designed trials assessing long-term efficacy and safety of opioids for CNCP and CLBP.

Is Buprenorphine Effective for Chronic Pain? A Systematic Review and Meta-analysis

OBJECTIVE

The objective was to perform a systematic review and meta-analysis of the literature on the effects of buprenorphine on chronic pain outcomes (i.e., patient-reported pain intensity) in patients with and without opioid use disorder (OUD).

DESIGN

Ovid/Medline, PubMed, Embase, and the Cochrane Library were searched for studies that explored the effectiveness (in reducing pain) of buprenorphine treatment for chronic pain patients with and without a history of OUD. Randomized controlled trials and observational studies were included in the review.

METHODS

Two separate searches were conducted to identify buprenorphine trials that included chronic pain patients either with or without OUD. Five studies used validated pain report measures and included a chronic pain population with OUD. Nine studies used validated report measures and included chronic pain patients without OUD. Meta-analysis was performed using the R, version 3.2.2, Metafor package, version 1.9-7.

RESULTS

The meta-analysis revealed that buprenorphine has a beneficial effect on pain intensity overall, with a small mean effect size in patients with comorbid chronic pain and OUD and a moderate- to large-sized effect in chronic pain patients without OUD.

CONCLUSIONS

Our results indicate that buprenorphine is modestly beneficial in reducing pain intensity in patients without OUD. Although informative, these findings should be carefully interpreted due to the small amount of data available and the variation in study designs.

Safety and effectiveness of once-daily Hysingla extended-release tablets in patients with baseline depression or anxiety

AIM

Long-term safety and effectiveness of a once-daily, single-entity, extended-release formulation of hydrocodone bitartrate (HYD) for the treatment of moderate to severe noncancer and nonneuropathic pain among patients with and without concurrent depression/anxiety at baseline.

MATERIALS & METHODS

Post hoc analysis.

RESULTS

HYD demonstrated a safety profile consistent with μ-opioid agonists: Serious adverse events in 12% patients with depression/anxiety including four deaths; 6% without depression/anxiety including one death. All pain scores declined by ≥2 points and mean daily HYD dose remained stable in both subgroups.

CONCLUSION

More serious adverse events occurred among patients with comorbid depression/anxiety at baseline than among those without. HYD provided stable and effective analgesia for 52 weeks among chronic pain patients with and without comorbid depression/anxiety at baseline.

Differences in opioid prescribing in low back pain patients with and without depression: a cross-sectional study of a national sample from the United States

Introduction

Low back pain (LBP) is among the leading indications for the prescription of opioid analgesics in clinical practice. There is increasing evidence suggesting that these agents may have diminished efficacy in the treatment of LBP.

Objectives

We evaluated the relationship between depression, the probability of receiving an opioid prescription, and the amount of morphine equivalent amounts prescribed per year among patients with LBP using nationwide data.

Methods

A cross-sectional analysis was performed on existing data from the Medical Expenditure Panel Survey data set from the period 2004 to 2009. Demographic, medical condition, Patient Health Questionnaire-2 responses, and prescription drug information were obtained on 56,811,864 weighted person-years of data from individuals aged 18 to 65 with an ICD-9 code specific to LBP.

Results

Increases in PHQ-2 score, as well a positive screen for depression, were associated with an increased probability of being prescribed opioid therapy and more morphine equivalents per year.

Conclusion

Analysis of a nationwide sample of patients with LBP shows an association between depression and higher rates of opioid prescribing after controlling for several known cofounders. Clinicians prescribing opioids in LBP populations that rely on clinical trial results that exclude depressed patients may misjudge the risks and benefits of this class of therapy.

Understanding Treatment Effect Terminology in Pain and Symptom Management Research

Within health services and medical research, there is a wide variety of terminology related to treatment effects. Understanding differences in types of treatment effects is especially important in pain and symptom management research where nonexperimental and quasiexperimental observational data analysis is common. We use the example of a palliative care consultation team leader considering implementation of a medication reconciliation program and a care-coordination intervention reported in the literature to illustrate population-level and conditional treatment effects and to highlight the sensitivity of values of treatment effects to sample selection and treatment assignment. Our goal is to facilitate appropriate reporting and interpretation of study results and to help investigators understand what information a decision maker needs when deciding whether to implement a treatment. Greater awareness of the reasons why treatment effects may differ across studies of the same patients in the same treatment settings can help policy makers and clinicians understand to whom a study's results may be generalized.