Efficacy and Safety of Pregabalin for the Treatment of Neuropathic Pain in Patients Undergoing Hemodialysis

Evaluation of Gabapentin and Pregabalin Use in Hospitalized Patients With Decreased Kidney Function

Background: Gabapentin and pregabalin are well-tolerated medications primarily cleared by the kidney. Patients receiving higher gabapentinoid doses with decreased kidney function may be at an increased risk of adverse effects (AEs), but limited evidence exists evaluating gabapentinoid dosing and AEs in this population. Objective: To determine whether patients with decreased creatinine clearance (CrCl) experienced increased frequency of AEs related to gabapentinoid dose at hospital admission. Methods: Single-center retrospective cohort study in adults with a gabapentinoid prescription and serum creatinine measurement documented on hospital admission. The primary outcome was the appropriateness of gabapentinoid prescription based on CrCl (stratified by CrCl ≥60 mL/min, <60 mL/min, 15-29 mL/min, and <15 mL/min) at admission. Secondary outcomes included the incidence of AEs related to gabapentinoids and concomitant opioid and psychiatric prescriptions. Results: A total of 286 patients were included in this study (gabapentin n = 234, pregabalin n = 52). Patients with a CrCl <60 mL/min and doses above the manufacturer's recommendation were prescribed gabapentin (34%) and pregabalin (22.7%). For patients with a CrCl of 15 to 29 mL/min and <15 mL/min groups, inappropriately high doses were prescribed for gabapentin (48.8%) and pregabalin (45%). A significant increase in recorded falls (P = 0.029) was identified in patients with a CrCl <60 mL/min. Concomitant opioid and psychiatric medications contributed to a higher prevalence of AEs regardless of CrCl. Conclusions: Patients with a CrCl <60 mL/min were frequently prescribed inappropriately high doses of gabapentinoids. The relationship between gabapentinoid dosing, kidney function, and the incidence of gabapentinoid-related AEs at hospital admission requires larger, multicentre studies.

Comparison of Pregabalin and Ketotifen in Treatment of Uremic Pruritus in Hemodialysis Patients

This study aims to compare the efficiency of Pregabalin and Ketotifen in treatment of uremic pruritus in hemodialysis (HD) patients. Thirty HD patients were randomly divided into two groups: A (Pregabalin 50 mg 3 times a day) and B (Ketotifen 1mg twice a day). Efficacy of treatment and quality of life were weekly evaluated by visual analogue scale (VAS) and Itchy Quality of life, respectively. There was no significant difference between the two groups regarding demographic features, laboratory data, quality of life, and VAS before treatment. In the second week of treatment, the pruritus intensity was significantly lower in the Pregabalin group than the Ketotifen group (p=0.026). The mean of life quality was significantly lower in Ketotifen than Pregabalin group in weeks 1, 2, and 4 (P=0.001, P=0.001, and P=0.036, respectively). There was no significant difference between the two groups regarding the side effects of drugs. This study showed that a higher dose of Pregabalin could be a more effective treatment than Ketotifen without additive side effects in improving the quality of life in dialysis patients. This article is protected by copyright. All rights reserved.

Analgesic use and associated adverse events in patients with chronic kidney disease: a systematic review and meta-analysis

BACKGROUND

Treating pain in the context of chronic kidney disease (CKD) is challenging because of altered pharmacokinetics and pharmacodynamics, with an increased risk of toxicity and drug adverse events in this population. The aims of this systematic review and meta-analysis were to assess the prevalence of analgesic use and establish the risk of analgesics-related adverse events, in patients with CKD.

METHODS

Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. Medline, Embase, CINAHL, and CENTRAL were searched until January 2021. Random-effects meta-analyses and meta-regression were conducted to pool and summarise prevalence data and measures of association between analgesic use and adverse events.

RESULTS

Sixty-two studies relevant to the prevalence of analgesic use and 33 to analgesic-related adverse events were included, combining data on 2.3 and 3 million individuals, respectively. Pooled analyses found that 41% (95% confidence interval [CI], 35-48) of the CKD population regularly use analgesia. The annual period prevalence was estimated at 50% for opioids and 21% for nonsteroidal anti-inflammatory drugs (NSAID). Overall, 20% and 7% of patients with CKD are on chronic opioid or NSAID therapy, respectively. Opioid use was associated with an increased risk of death (1.61; 95% CI, 1.12-2.31; n= 7, I²= 91%), hospitalisation (1.38; 95% CI, 1.32-1.45; n=2, I²=0%), and fractures (1.51; 95% CI, 1.16-1.96; n=3, I²=54%).

CONCLUSION

High levels of analgesic consumption and related serious adverse outcomes were found in patients with CKD. Consideration needs to be given to how these patients are assessed and managed in order to minimise harms and improve outcomes.

CLINICAL TRIAL REGISTRATION

CRD42019156491 (PROSPERO).

Analgesic Use in Patients With Advanced Chronic Kidney Disease: A Systematic Review and Meta-Analysis

Background:

Pain is common in patients with chronic kidney disease (CKD). Analgesics may be appropriate for some CKD patients.

Objectives:

To determine the prevalence of overall analgesic use and the use of different types of analgesics including acetaminophen, nonsteroidal anti-inflammatory drugs (NSAIDs), adjuvants, and opioids in patients with CKD.

Design:

Systematic review and meta-analysis.

Setting:

Interventional and observational studies presenting data from 2000 or later. Exclusion criteria included acute kidney injury or studies that limited the study population to a specific cause, symptom, and/or comorbidity.

Patients:

Adults with stage 3-5 CKD including dialysis patients and those managed conservatively without dialysis.

Measurements:

Data extracted included title, first author, design, country, year of data collection, publication year, mean age, stage of CKD, prevalence of analgesic use, and the types of analgesics prescribed.

Methods:

Databases searched included MEDLINE, CINAHL, EMBASE, and Cochrane Library. Two reviewers independently screened all titles and abstracts, assessed potentially relevant articles, and extracted data. We estimated pooled prevalence of analgesic use and the I2 statistic was computed to measure heterogeneity. Random-effects models were used to account for variations in study design and sample populations, and a double arcsine transformation of the prevalence variables was used to accommodate potential overweighting of studies with very large or very small prevalence measurements. Sensitivity analyses were performed to determine the magnitude of publication bias and assess possible sources of heterogeneity.

Results:

Forty studies were included in the analysis. The prevalence of overall analgesic use in the random-effects model was 50.8%. The prevalence of acetaminophen, NSAIDs, and adjuvant use was 27.5%, 17.2%, and 23.4%, respectively, while the prevalence of opioid use was 23.8%. Due to the possibility of publication bias, the actual prevalence of acetaminophen use in patients with advanced CKD may be substantially lower than this meta-analysis indicates. A trim-and-fill analysis decreased the pooled prevalence estimate of acetaminophen use to 5.4%. The prevalence rate for opioid use was highly influenced by 2 large US studies. When these were removed, the estimated prevalence decreased to 17.3%.

Limitations:

There was a lack of detailed information regarding the analgesic regimen (such as specific analgesics used within each class and inconsistent accounting for patients on multiple drugs and the use of over-the-counter analgesics such as acetaminophen and NSAIDs), patient characteristics, type of pain being treated, and the outcomes of treatment. Data on adjuvant use were very limited. These results, therefore, must be interpreted with caution.

Conclusions:

There was tremendous variability in the prescribing patterns of both nonopioid and opioid analgesics within and between countries suggesting widespread uncertainty about the optimal pharmacological approach to treating pain. Further research that incorporates robust reporting of analgesic regimens and links prescribing patterns to clinical outcomes is needed to guide optimal clinical practice.

Assessing and Treating Chronic Pain in Patients with End-Stage Renal Disease

Pain is one of the most common symptoms among patients with end-stage renal disease (ESRD), and is often under recognized and not adequately managed in hemodialysis (HD) patients. Barriers to adequate pain management include poor awareness of the problem, insufficient medical education, fears of possible drug-related side effects, and common misconceptions about the inevitability of pain in elderly and HD patients. Caregivers working in HD should be aware of the possible consequences of inadequate pain assessment and management. Common pain syndromes in HD patients include musculoskeletal diseases and metabolic neuropathies, associated with typical intradialytic pain. Evaluating the etiology, nature, and intensity of pain is crucial for choosing the correct analgesic. A mechanism-based approach to pain management may result in a better outcome. Pharmacokinetic considerations on clearance alterations and possible toxicity in patients with ESRD should drive the right analgesic prescription. Comorbidities and polymedications may increase the risk of drug-drug interactions, therefore drug metabolism should be taken into account when selecting analgesic drugs. Automedication is common among HD patients but should be avoided to reduce the risk of hazardous drug administration. Further research is warranted to define the efficacy and safety of analgesic drugs and techniques in the context of patients with ESRD as generalizing information from studies conducted in the general population could be inappropriate and potentially dangerous. A multidisciplinary approach is recommended for the management of complex pain syndromes in frail patients, such as those suffering from ESRD.

An Updated Overview on Therapeutic Drug Monitoring of Recent Antiepileptic Drugs

Given the distinctive characteristics of both epilepsy and antiepileptic drugs (AEDs), therapeutic drug monitoring (TDM) can make a significant contribution to the field of epilepsy. The measurement and interpretation of serum drug concentrations can be of benefit in the treatment of uncontrollable seizures and in cases of clinical toxicity; it can aid in the individualization of therapy and in adjusting for variable or nonlinear pharmacokinetics; and can be useful in special populations such as pregnancy. This review examines the potential for TDM of newer AEDs such as eslicarbazepine acetate, felbamate, gabapentin, lacosamide, lamotrigine, levetiracetam, perampanel, pregabalin, rufinamide, retigabine, stiripentol, tiagabine, topiramate, vigabatrin, and zonisamide. We describe the relationships between serum drug concentration, clinical effect, and adverse drug reactions for each AED as well as the different analytical methods used for serum drug quantification. We discuss retrospective studies and prospective data on the serum drug concentration-efficacy of these drugs and present the pharmacokinetic parameters, oral bioavailability, reference concentration range, and active metabolites of newer AEDs. Limited data are available for recent AEDs, and we discuss the connection between drug concentrations in terms of clinical efficacy and nonresponse. Although we do not propose routine TDM, serum drug measurement can play a beneficial role in patient management and treatment individualization. Standardized studies designed to assess, in particular, concentration-efficacy-toxicity relationships for recent AEDs are urgently required.

Neuropathic Corneal Pain: Approaches for Management

Neuropathic pain is caused by a primary lesion or dysfunction of the nervous system and can occur in the cornea. However, neuropathic corneal pain (NCP) is currently an ill-defined disease. Patients with NCP are extremely challenging to manage, and evidence-based clinical recommendations for the management of patients with NCP are scarce. The objectives of this review are to provide guidelines for diagnosis and treatment of patients with NCP and to summarize current evidence-based literature in this area. We performed a systematic literature search of all relevant publications between 1966 and 2017. Treatment recommendations are, in part, based on methodologically sound randomized controlled trials (RCTs), demonstrating superiority to placebo or relevant control treatments, and on the consistency of evidence, degree of efficacy, and safety. In addition, the recommendations include our own extensive experience in the management of these patients over the past decade. A comprehensive algorithm, based on clinical evaluation and complementary tests, is presented for diagnosis and subcategorization of patients with NCP. Recommended first-line topical treatments include neuroregenerative and anti-inflammatory agents, and first-line systemic pharmacotherapy includes tricyclic antidepressants and an anticonvulsant. Second-line oral treatments recommended include an opioid-antagonist and opiate analgesics. Complementary and alternative treatments, such as cardiovascular exercise, acupuncture, omega-3 fatty acid supplementation, and gluten-free diet, may have additional benefits, as do potential noninvasive and invasive procedures in recalcitrant cases. Medication selection should be tailored on an individual basis, considering side effects, comorbidities, and levels of peripheral and centralized pain. Nevertheless, there is an urgent need for long-term studies and RCTs assessing the efficacy of treatments for NCP.