Evidence, regulation and 'rational' prescribing: the case of gabapentin for neuropathic pain

Cost-Related Non-Adherence to Prescribed Medicines: What Are Physicians' Moral Duties?

As the price of pharmaceuticals and biologicals rises so does the number of patients who cannot afford them. In this article, we argue that physicians have a moral duty to help patients access affordable medicines. We offer three grounds to support our argument: (i) the aim of prescribing is to improve health and well-being which can only be realized with secure access to treatment; (ii) there is no morally significant difference between medicines being unavailable and medicines being unaffordable, so the steps physicians are willing to take in the first case should extend to the second; and (iii) as the primary stakeholder with a duty to put the individual patient's interests first, the medical professional has a duty to address cost-barriers to patient care. In articulating this duty, we take account of important epistemic and control conditions that must be met for the attribution of this duty to be justified.

Which older adults are at highest risk of prescribing cascades? A national study of the gabapentinoid-loop diuretic cascade

BACKGROUND

Prescribing cascades are important contributors to polypharmacy. Little is known about which older adults are at highest risk of experiencing prescribing cascades. We explored which older veterans are at highest risk of the gabapentinoid (including gabapentin and pregabalin)-loop diuretic (LD) cascade, given the dramatic increase in gabapentinoid prescribing in recent years.

METHODS

Using Veterans Affairs and Medicare claims data (2010-2019), we performed a prescription sequence symmetry analysis (PSSA) to assess loop diuretic initiation before and after gabapentinoid initiation among older veterans (≥66 years). To identify the cascade, we calculated the adjusted sequence ratio (aSR), which assesses the temporality of LD relative to gabapentinoid initiation. To explore high-risk groups, we used multivariable logistic regression with prescribing order modeled as a binary dependent variable. We calculated adjusted odds ratios (aORs), measuring the extent to which factors are associated with one prescribing order versus another.

RESULTS

Of 151,442 veterans who initiated a gabapentinoid, there were 1,981 patients who initiated a LD within 6 months after initiating a gabapentinoid compared to 1,599 patients who initiated a LD within 6 months before initiating a gabapentinoid. In the gabapentinoid-LD group, the mean age was 73 years, 98% were male, 13% were Black, 5% were Hispanic, and 80% were White. Patients in each group were similar across patient and health utilization factors (standardized mean difference <0.10 for all comparisons). The aSR was 1.23 (95% CI: 1.13, 1.34), strongly suggesting the cascade's presence. People age ≥85 years were less likely to have the cascade (compared to 66-74 years; aOR 0.74, 95% CI: 0.56-0.96), and people taking ≥10 medications were more likely to have the cascade (compared to 0-4 drugs; aOR 1.39, 95% CI: 1.07-1.82).

CONCLUSIONS

Among older adults, those who are younger and taking many medications may be at higher risk of the gabapentinoid-LD cascade, contributing to worsening polypharmacy and potential drug-related harms. We did not identify strong predictors of this cascade, suggesting that prescribing cascade prevention efforts should be widespread rather than focused on specific subgroups.

Do doctors have a responsibility to help patients import medicines from abroad?

Almost any medicine can be purchased online from abroad. Many high-income countries permit individuals to import medicines for their personal use. However, those who import medicines face the risk of purchasing poor-quality products that may not work, or that may even harm them. Many people are willing to accept this risk for the opportunity to purchase more affordable medicines. This is especially true of individuals from low socioeconomic backgrounds who already struggle to afford the medicines they need if they are not subsidised by insurers or if copayments are high. As medicine prices and out-of-pocket healthcare spending continue to climb, the online marketplace provides an important alternative for individuals in high-income countries to source medicines. In this article, I argue that doctors have a responsibility to help patients access medicines online and I propose a framework that can be used to facilitate responsible personal importation.

Gabapentin initiation in the inpatient setting: A characterization of prescribing

Disclaimer

In an effort to expedite the publication of articles related to the COVID-19 pandemic, AJHP is posting these manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time.

Purpose

Gabapentin is a widely prescribed analgesic with increased popularity over recent years. Previous studies have characterized use of gabapentin in the outpatient setting, but minimal data exist for its initiation in the inpatient setting. The objective of this study was to characterize the prescribing patterns of gabapentin when it was initiated in the inpatient setting.

Methods

This was a retrospective cohort study of a random sample of adult patients who received new-start gabapentin during hospital admission. Patients for whom gabapentin was prescribed as a home medication, with one-time, on-call, or as-needed orders, or who died during hospital admission were excluded. The primary outcome was characterization of the gabapentin indication; secondary outcomes included the starting and discharge doses, the number of dose titrations, the rate of concomitant opioid prescribing, and pain clinic follow-up. Patients were stratified by surgical vs nonsurgical status.

Results

A total of 464 patients were included, 283 (61.0%) of whom were surgical and 181 (39.0%) of whom were nonsurgical. The cohort was 60% male with a mean (SD) age of 56 (18) years; surgical patients were younger and included more women. The most common indications for surgical patients were multimodal analgesia (161; 56.9%), postoperative pain (53; 18.7%), and neuropathic pain (26; 9.2%), while those for nonsurgical patients were neuropathic pain (72; 39.8%) and multimodal analgesia (53; 29.3%). The mean starting dose was similar between the subgroups (613 mg for surgical patients vs 560 mg for nonsurgical patients; P = 0.196). A total of 51.6% vs 81.8% of patients received gabapentin at discharge (P &lt; 0.0001), while referral/follow-up to a pain clinic was minimal and similar between the subgroups (1.1% vs 3.9%; P = 0.210).

Conclusion

Inpatients were commonly initiated on gabapentin for generalized indications, with approximately half discharged on gabapentin. Further studies are needed to assess the impact of this prescribing on chronic utilization.

Is gabapentin a safe and effective treatment for nonneuropathic pain?

ABSTRACT

A review of the recent literature found that compared with placebo or other pain medications, gabapentin did not significantly reduce nonneuropathic pain. The drug also is associated with an increased risk of adverse reactions, including somnolence, dizziness, and nausea. Given the lack of efficacy and risk of adverse reactions, gabapentin should not be used for nonneuropathic pain.

Outpatient Off-Label Gabapentin Use for Psychiatric Indications Among U.S. Adults, 2011-2016

OBJECTIVE

Gabapentin is widely prescribed off label in medical practice, including psychiatry. The U.S. Food and Drug Administration (FDA) warned of risks associated with gabapentin combined with central nervous system depressant (CNS-D) drugs, which are commonly prescribed in psychiatric treatment. This study examined off-label outpatient gabapentin use for psychiatric indications and concomitant CNS-D medication use.

METHODS

National Ambulatory Care Medical Survey data (2011-2016) were used to identify encounters involving gabapentin (gabapentin visits) for adults (ages ≥18) (N=5,732). FDA-approved uses and off-label psychiatric use indications were identified with ICD-9-CM and ICD-10-CM diagnosis codes. CNS-D drugs examined were opioids, benzodiazepines, sedatives-hypnotics, antidepressants, antipsychotics, first-generation antihistamines, and skeletal muscle relaxants. Concomitance was prescription of one or more CNS-D medications at the same visit. Visits were stratified by provider type and specialty.

RESULTS

Between 2011 and 2016, 2.8% of visits listed gabapentin prescriptions (weighted estimate of 129.6 million visits). A small proportion (<1%) listed an FDA-approved indication. Among off-label gabapentin visits, 5.3% listed a depressive disorder, 3.5% an anxiety disorder, and 1.8% bipolar disorder. Over 6 years, 58.4% of off-label gabapentin visits listed one or more concomitant CNS-D medications, most frequently antidepressants (24.3%), opioids (22.9%), and benzodiazepines (17.3%). Most gabapentin visits were with primary care providers (34.9%) and other provider specialties (i.e., not primary care, neurology, or psychiatry) (48.1%).

CONCLUSION

In this nationally representative sample, <1% of outpatient gabapentin use was for approved indications. High concomitant use of CNS-D drugs and off-label gabapentin for psychiatric diagnoses underlines the need for improved communication about safety.

Safety of Gabapentin Prescribed for Any Indication in a Large Clinical Cohort of 571,718 US Veterans with and without Alcohol Use Disorder

BACKGROUND

Gabapentin is prescribed for seizures and pain and has efficacy for treating alcohol use disorder (AUD) starting at doses of 900 milligrams per day (mg/d). Recent evidence suggests safety concerns associated with gabapentin including adverse neurologic effects. Individuals with hepatitis C (HCV), HIV, or AUD may be at increased risk due to comorbidities and potential medication interactions.

METHODS

We identified patients prescribed gabapentin for ≥ 60 days for any indication between 2002 and 2015. We propensity-score matched each gabapentin-exposed patient with up to 5 gabapentin-unexposed patients. We followed patients for 2 years or until diagnosed with (i) falls or fractures, or (ii) altered mental status using validated ICD-9 diagnostic codes. We used Poisson regression to estimate incidence rates and relative risk (RR) of these adverse events in association with gabapentin exposure overall and stratified by age, race/ethnicity, sex, HCV, HIV, AUD, and dose.

RESULTS

Incidence of falls or fractures was 1.81 per 100 person-years (PY) among 140,310 gabapentin-exposed and 1.34/100 PY among 431,408 gabapentin-unexposed patients (RR 1.35, 95% confidence interval [CI] 1.28 to 1.44). Incidence of altered mental status was 1.08/100 PY among exposed and 0.97/100 PY among unexposed patients, RR of 1.12 (95% CI 1.04 to 1.20). Excess risk of falls or fractures associated with gabapentin exposure was observed in all subgroups except patients with HCV, HIV, or AUD; however, these groups had elevated incidence regardless of exposure. There was a clear dose-response relationship for falls or fractures with highest risk observed among those prescribed ≥ 2,400 mg/d (RR 1.90, 95% CI 1.50 to 2.40). Patients were at increased risk for altered mental status at doses 600 to 2,399 mg/d; however, low number of events in the highest dose category limited power to detect a statistically significant association ≥ 2,400 mg/d.

CONCLUSIONS

Gabapentin is associated with falls or fractures and altered mental status. Clinicians should be monitoring gabapentin safety, especially at doses ≥ 600 mg/d, in patients with and without AUD.

"Some sort of fantasy land": A qualitative investigation of appropriate prescribing in cancer care

RATIONALE, AIMS, AND OBJECTIVES

Increasing the appropriateness of prescribing has long been a focus of government, non-government, and professional organizations. Progress towards this is made difficult by the fact appropriate prescribing remains inconsistently defined and is the subject of ongoing intense disagreement. In this study, we attempted to understand why this is the case within the context of oncology and haematology.

METHODS

We performed a qualitative empirical analysis of semi-structured interviews with 16 Australian oncologists and haematologists.

RESULTS

We found that oncologists framed appropriate prescribing in terms of the following inter-related, and at times opposed, values: civic mindedness, hope and compassion, realism, and virtue in motivation.

CONCLUSIONS

These values cannot be ranked a priori, and therefore, any definition of appropriate prescribing must be aligned with what communities want from their health system. When one value is privileged over another in any specific context, a compelling argument must be provided to justify the choice. In an era of shared decision making, patient rights, and high-cost medicines, we need to reassess what we mean by appropriate prescribing in cancer care.

Gabapentin and pregabalin to treat aggressivity in dementia: a systematic review and illustrative case report

AIMS

The prevalence of dementia is rising as life expectancy increases globally. Behavioural and psychological symptoms of dementia (BPSD), including agitation and aggression, are common, presenting a challenge to clinicians and caregivers.

METHODS

Following PRISMA guidelines, we systematically reviewed evidence for gabapentin and pregabalin against BPSD symptoms of agitation or aggression in any dementia, using six databases (Pubmed, CINHL, PsychINFO, HealthStar, Embase, and Web of Science). Complementing this formal systematic review, an illustrative case of a patient with BPSD in mixed Alzheimer's/vascular dementia, who appeared to derive benefits in terms of symptom control and functioning from the introduction of gabapentin titrated up to 3600 mg day^-1 alongside other interventions, is presented.

RESULTS

Twenty-four relevant articles were identified in the systematic review. There were no randomized trials. Fifteen papers were original case series/case reports of patients treated with these compounds, encompassing 87 patients given gabapentin and six given pregabalin. In 12 of 15 papers, drug treatment was effective in the majority of cases. The remaining nine papers were solely reviews, of which two were described as systematic but predated PRISMA guidelines. Preliminary low-grade evidence based on case series and case reviews suggests possible benefit of gabapentin and pregabalin in patients with BPSD in Alzheimer's disease. These benefits cannot be confirmed until well-powered randomized controlled trials are undertaken. Evidence in frontotemporal dementia is lacking.

CONCLUSION

Gabapentin and pregabalin could be considered for BPSD when medications having stronger evidence bases (risperidone, other antipsychotics, carbamazepine and citalopram) have been ineffective or present unacceptable risks of adverse outcomes.

Gabapentin for Off-Label Use: Evidence-Based or Cause for Concern?

Gabapentin is widely used in the United States for a number of off-label indications, often as an alternative to opioid therapy. Increasing evidence has emerged suggesting that gabapentin may not be as benign as once thought and may be associated with substance abuse in concert with opioids. With concerns for safety mounting, it is prudent to examine the efficacy of gabapentin across its many uses to understand the risk-benefit balance. Reviews on off-label indications such as migraine, fibromyalgia, mental illness, and substance dependence have found modest to no effect on relevant clinical outcomes. This high-quality evidence has often been overshadowed by uncontrolled studies and limited case reports. Furthermore, the involvement of gabapentin in questionable marketing schemes further calls its use into question. Overall, clinicians should exercise rigorous appraisal of the available evidence for a given indication, and researchers should conduct larger, higher-quality studies to better assess the efficacy of gabapentin for many of its off-label uses.

Challenges to the validity of using medicine labels to categorize clinical behavior: An empirical and normative critique of "off-label" prescribing

This study aimed to determine whether the label status of a medicine penetrates into the clinical reasoning of Australian medical practitioners and to explore the possible reasons for our findings using semistructured interviews with 14 Australian physicians. The interviews revealed 3 broad catalysts for off-label prescribing. The first of these was lack of awareness or understanding of the regulatory process in general and labels more specifically. The second was the perception that labels are not meaningful guides for clinical practice. The third was the recognition of alternative mechanisms for ensuring safe, rational, and evidence-based prescribing occurs. This research suggests that Australian physicians do not consider whether a medicine is off-label to be a reliable measure of the appropriateness of their prescribing practices. Rather, the legitimacy of prescribing practices is determined by the abilities, skills, and knowledge base of particular prescribers by a culture that encourages and supports evidence-based practice, and safe prescribing. Although labels are of minimal clinical significance, there are real conceptual, practical, and moral problems associated with conflating "good" or "better" practice with "on-label" practice, and "bad" or "worse" practice with off-label prescribing as often occurs. To ascribe greater meaning to the term "off-label" than is warranted can have the unintended consequence of casting suspicion on and making it more difficult for physicians to provide appropriate clinical care. We conclude that labeling can, in some cases, provide assurances to both clinicians and patients that their medications have been demonstrated to be safe and effective, but that clinicians should be able to continue to prescribe responsibly off-label without having any stigma attached to their practice.

Prescription of Long-Acting Opioids and Mortality in Patients With Chronic Noncancer Pain

IMPORTANCE

Long-acting opioids increase the risk of unintentional overdose deaths but also may increase mortality from cardiorespiratory and other causes.

OBJECTIVE

To compare all-cause mortality for patients with chronic noncancer pain who were prescribed either long-acting opioids or alternative medications for moderate to severe chronic pain.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective cohort study between 1999 and 2012 of Tennessee Medicaid patients with chronic noncancer pain and no evidence of palliative or end-of-life care.

EXPOSURES

Propensity score-matched new episodes of prescribed therapy for long-acting opioids or either analgesic anticonvulsants or low-dose cyclic antidepressants (control medications).

MAIN OUTCOMES AND MEASURES

Total and cause-specific mortality as determined from death certificates. Adjusted hazard ratios (HRs) and risk differences (difference in incidence of death) were calculated for long-acting opioid therapy vs control medication.

RESULTS

There were 22,912 new episodes of prescribed therapy for both long-acting opioids and control medications (mean [SD] age, 48 [11] years; 60% women). The long-acting opioid group was followed up for a mean 176 days and had 185 deaths and the control treatment group was followed up for a mean 128 days and had 87 deaths. The HR for total mortality was 1.64 (95% CI, 1.26-2.12) with a risk difference of 68.5 excess deaths (95% CI, 28.2-120.7) per 10,000 person-years. Increased risk was due to out-of-hospital deaths (154 long-acting opioid, 60 control deaths; HR, 1.90; 95% CI, 1.40-2.58; risk difference, 67.1; 95% CI, 30.1-117.3) excess deaths per 10,000 person-years. For out-of-hospital deaths other than unintentional overdose (120 long-acting opioid, 53 control deaths), the HR was 1.72 (95% CI, 1.24-2.39) with a risk difference of 47.4 excess deaths (95% CI, 15.7-91.4) per 10,000 person-years. The HR for cardiovascular deaths (79 long-acting opioid, 36 control deaths) was 1.65 (95% CI, 1.10-2.46) with a risk difference of 28.9 excess deaths (95% CI, 4.6-65.3) per 10,000 person-years. The HR during the first 30 days of therapy (53 long-acting opioid, 13 control deaths) was 4.16 (95% CI, 2.27-7.63) with a risk difference of 200 excess deaths (95% CI, 80-420) per 10,000 person-years.

CONCLUSIONS AND RELEVANCE

Prescription of long-acting opioids for chronic noncancer pain, compared with anticonvulsants or cyclic antidepressants, was associated with a significantly increased risk of all-cause mortality, including deaths from causes other than overdose, with a modest absolute risk difference. These findings should be considered when evaluating harms and benefits of treatment.