Post hoc analysis of pregabalin vs. non-pregabalin treatment in patients with cancer-related neuropathic pain: better pain relief, sleep and physical health

Opposing inflammatory biomarker responses to sleep disruption in cancer patients before and during oncological therapy

Background

Sleep disruption is known to be highly prevalent in cancer patients, aggravated during oncological treatment and closely associated with reduced quality of life, therapeutic outcome and survival. Inflammatory factors are associated with sleep disruption in healthy individuals and cancer patients, but heterogeneity and robustness of inflammatory factors associated with sleep disruption and how these are affected by oncological therapy remain poorly understood. Furthermore, due to the complex crosstalk between sleep-, and therapy-associated factors, including inflammatory factors, there are currently no established biomarkers for predicting sleep disruption in patients undergoing oncological therapy.

Methods

We performed a broad screen of circulating biomarkers with immune-modulating or endocrine functions and coupled these to self-reported sleep quality using the Medical Outcomes Study (MOS) sleep scale. Ninety cancer patients with gastrointestinal, urothelial, breast, brain and tonsillar cancers, aged between 32 and 86 years, and scheduled for adjuvant or palliative oncological therapy were included. Of these, 71 patients were evaluable. Data was collected immediately before and again 3 months after onset of oncological therapy.

Results

Seventeen among a total of 45 investigated plasma proteins were found to be suppressed in cancer patients exhibiting sleep disruption prior to treatment onset, but this association was lost following the first treatment cycle. Patients whose sleep quality was reduced during the treatment period exhibited significantly increased plasma levels of six pro-inflammatory biomarkers (IL-2, IL-6, IL-12, TNF-a, IFN-g, and GM-CSF) 3 months after the start of treatment, whereas biomarkers with anti-inflammatory, growth factor, immune-modulatory, or chemokine functions were unchanged.

Conclusion

Our work suggests that biomarkers of sleep quality are not valid for cancer patients undergoing oncological therapy if analyzed only at a single timepoint. On the other hand, therapy-associated increases in circulating inflammatory biomarkers are closely coupled to reduced sleep quality in cancer patients. These findings indicate a need for testing of inflammatory and other biomarkers as well as sleep quality at multiple times during the patient treatment and care process.

Duloxetine and pregabalin in neuropathic pain of lung cancer patients

INTRODUCTION

Neuropathic pain occurs in 1% of the population and is difficult to manage. This chronic pain causes psychological distress and impacts patient's quality of life, especially in cancer patients. The aim of this study was to show and compare the efficacy of pregabalin and duloxetine, which are reported in the group of first-line treatment at European Federation of Neurological Societies (EFNS) guidelines on the pharmacological treatment of neuropathic pain (2010 revision) in lung cancer patients by using visual analogue scale (VAS) and Leeds Assessment of Neuropathic Symptoms and Sign (LANSS).

PATIENTS AND METHODS

A prospective, randomized, open label, 3 month of study was conducted. A total of 44 patients that were diagnosed with neuropathic pain (14 women and 30 men) were included in the study. Patient's LANSS and VAS values were recorded before treatment. Then, 22 patients undergo pregabalin and 22 patients undergo duloxetine therapy. But due to side effects (dizziness, constipation), two patients had stopped to use pregabalin. Their LANSS and VAS values were recorded after 1 and 3 months of therapy.

RESULTS

When we compare LANSS and VAS scores before treatment, after 1 and 3 months of treatment with pregabalin and duloxetine, a significant decrease was observed in both groups at the 1 and 3 months (p < .01). Duloxetine is superior to pregabalin in reducing the LANSS scores when we compare two groups.

CONCLUSIONS

Both duloxetine and pregabalin are effective in the treatment of neuropathic pain of lung cancer patients. And as far as we know, this is the first study comparing the efficacy of duloxetine and pregabalin in the neuropathic pain of lung cancer patients.

Analgesic effectiveness and tolerability of oral oxycodone/naloxone and pregabalin in patients with lung cancer and neuropathic pain: an observational analysis

INTRODUCTION

Cancer-related pain has a severe negative impact on quality of life. Combination analgesic therapy with oxycodone and pregabalin is effective for treating neuropathic cancer pain. We investigated the efficacy and tolerability of a dose-escalation combination therapy with prolonged-release oxycodone/naloxone (OXN-PR) and pregabalin in patients with non-small-cell lung cancer and severe neuropathic pain.

METHODS

This was a 4-week, open-label, observational study. Patients were treated with OXN-PR and pregabalin. Average pain intensity ([API] measured on a 0-10 numerical rating scale) and neuropathic pain (Douleur Neuropathique 4) were assessed at study entry and at follow-up visits. The primary endpoint was response to treatment, defined as a reduction of API at T28 ≥30% from baseline. Secondary endpoints included other efficacy measures, as well as patient satisfaction and quality of life (Brief Pain Inventory Short Form), Hospital Anxiety and Depression Scale, and Symptom Distress Scale; bowel function was also assessed.

RESULTS

A total of 56 patients were enrolled. API at baseline was 8.0±0.9, and decreased after 4 weeks by 48% (4.2±1.9; P<0.0001 vs baseline); 46 (82.1%) patients responded to treatment. Significant improvements were also reported in number/severity of breakthrough cancer pain episodes (P=0.001), Brief Pain Inventory Short Form (P=0.0002), Symptom Distress Scale (P<0.0001), Hospital Anxiety and Depression Scale depression (P=0.0006) and anxiety (P<0.0001) subscales, and bowel function (P=0.0003). At study end, 37 (66.0%) patients were satisfied/very satisfied with the new analgesic treatment. Combination therapy had a good safety profile.

CONCLUSION

OXN-PR and pregabalin were safe and highly effective in a real-world setting of severe neuropathic cancer pain, with a high rate of satisfaction, without interference on bowel function.

Update on research-based interventions for anxiety in patients with cancer

Anxiety may begin at the moment a person is diagnosed with cancer and may fluctuate throughout the cancer trajectory as physical illness improves or declines. The purpose of this article is to present current evidence for nurses to implement interventions to reduce anxiety in patients who have cancer. The PubMed and CINAHL® databases were searched to identify relevant citations addressing interventions that treat or prevent anxiety symptoms in patients with cancer. Based on available evidence, the interventions addressed herein are categorized according to the Putting Evidence Into Practice (PEP®) rating schema. Interventions include pharmacologic and nonpharmacologic approaches to care, and meet criteria for three PEP categories: likely to be effective, effectiveness not established (the largest category of results), or effectiveness unlikely.

Effects of pregabalin in patients with hypnotic-dependent insomnia

STUDY OBJECTIVES

Long-term use of hypnotics runs the risk of dependency, and subjects usually experience difficulties in withdrawal. The objective of this study was to investigate the success of withdrawal using pregabalin and its efficacy on sleep in patients with hypnotic-dependent insomnia.

METHODS

We enrolled patients with hypnotic-dependent insomnia who were 18 years or older. The starting dosage of pregabalin was 75 mg/day and was increased up to as much as 300 mg/day, depending on the individual patient's condition, while tapering off hypnotics. After 4 weeks of titration, the final dosage amount was maintained for at least another 4 weeks. Sleep and clinical variables were evaluated at baseline and after treatment, using the Korean versions of various sleep questionnaires as well as polysomnography.

RESULTS

Forty subjects were enrolled, with a mean age of 52.0 ± 8.5 years, of whom 28 (70.0%) were women. Twenty-one (52.5%) subjects successfully withdrew from hypnotics. The duration of withdrawal was 42.1 ± 16.0 days (range: 27.0∼84.0). The mean pregabalin dose was 121.4 ± 69.0 mg/day (range: 75.0∼300.0). After pregabalin treatment, there was a significant improvement in the total score of the Pittsburgh Sleep Quality Index (15.0 ± 2.1, 8.9 ± 3.0, p < 0.001), and insomnia severity index (20.9 ± 4.3, 9.6 ± 4.4, p < 0.001); however, most of the sleep variables of the PSG showed no differences. The main adverse effects of pregabalin were nausea and dizziness.

CONCLUSIONS

Our results showed pregabalin may be a promising candidate for withdrawal from hypnotics and improved sleep in patients with hypnotic-dependent insomnia.

Efficacy and safety of pregabalin in patients with neuropathic cancer pain undergoing morphine therapy

AIM

To evaluate the efficacy and the safety of pregabalin (PGB)-morphine combination for the treatment of neuropathic cancer pain (NCP).

METHODS

In this double-blind, randomized, placebo (PL)-controlled crossover study, 40 cancer patients with severe NCP were randomized into two groups (20 per group): PGB-PL and PL-PGB. Patients in the PGB-PL group received PGB plus oral morphine in phase I, and PL plus oral morphine in phase II. The treatment sequence for the PL-PGB group was PL plus oral morphine in phase I, and PGB plus oral morphine in phase II. These 2-week treatment periods were separated by a 1-week washout period. The primary outcome measure was the decrements in morphine dose; secondary outcomes included quantitative assessments of sleep (rated according to the Medical Outcomes Study Sleep Scale), the Constipation Assessment Scale and adverse effects.

RESULTS

The mean minimal effective dose of morphine was 184.4 ± 69.9 mg/day in the period of PGB treatments, which was significantly lower than that of PL-controls (228.7 ± 66.9 mg/day; P < 0.001) and baseline (247.5 ± 80.0 mg/day; P < 0.001). Compared with PL, PGB resulted in a significant sleep improvement as measured by sleep disturbance, sleep quantity, and sleep problems index (P < 0.001), as well as a Constipation Assessment Scale reduction (P < 0.001). PGB resulted in a higher frequency of dry mouth and somnolence than PL (P < 0.05).

CONCLUSION

PGB enhances the efficacy of oral morphine and reduces dose-related adverse reactions. The PGB-morphine combination is an effective approach to controlling NCP.

Systematic review of sleep disorders in cancer patients: can the prevalence of sleep disorders be ascertained?

Although sleep is vital to all human functioning and poor sleep is a known problem in cancer, it is unclear whether the overall prevalence of the various types of sleep disorders in cancer is known. The purpose of this systematic literature review was to evaluate if the prevalence of sleep disorders could be ascertained from the current body of literature regarding sleep in cancer. This was a critical and systematic review of peer-reviewed, English-language, original articles published from 1980 through 15 October 2013, identified using electronic search engines, a set of key words, and prespecified inclusion and exclusion criteria. Information from 254 full-text, English-language articles was abstracted onto a paper checklist by one reviewer, with a second reviewer randomly verifying 50% (k = 99%). All abstracted data were entered into an electronic database, verified for accuracy, and analyzed using descriptive statistics and frequencies in SPSS (v.20) (North Castle, NY). Studies of sleep and cancer focus on specific types of symptoms of poor sleep, and there are no published prevalence studies that focus on underlying sleep disorders. Challenging the current paradigm of the way sleep is studied in cancer could produce better clinical screening tools for use in oncology clinics leading to better triaging of patients with sleep complaints to sleep specialists, and overall improvement in sleep quality.

Pregabalin in neuropathic pain: evidences and possible mechanisms

Pregabalin is an antagonist of voltage gated Ca2+ channels and specifically binds to alpha-2-delta subunit to produce antiepileptic and analgesic actions. It successfully alleviates the symptoms of various types of neuropathic pain and presents itself as a first line therapeutic agent with remarkable safety and efficacy. Preclinical studies in various animal models of neuropathic pain have shown its effectiveness in treating the symptoms like allodynia and hyperalgesia. Clinical studies in different age groups and in different types of neuropathic pain (peripheral diabetic neuropathy, fibromyalgia, post-herpetic neuralgia, cancer chemotherapy-induced neuropathic pain) have projected it as the most effective agent either as monotherapy or in combined regimens in terms of cost effectiveness, tolerability and overall improvement in neuropathic pain states. Preclinical studies employing pregabalin in different neuropathic pain models have explored various molecular targets and the signaling systems including Ca2+ channel-mediated neurotransmitter release, activation of excitatory amino acid transporters (EAATs), potassium channels and inhibition of pathways involving inflammatory mediators. The present review summarizes the important aspects of pregabalin as analgesic in preclinical and clinical studies as well as focuses on the possible mechanisms.

Randomized study of pregabalin in patients with cancer-induced bone pain

Introduction

Improvements are needed in the management of cancer-induced bone pain (CIBP). The objective of this study was to assess the efficacy and safety of pregabalin compared with placebo in the adjunctive treatment of patients with moderate to severe CIBP who were receiving opioids.

Methods

In this randomized, double-blind, placebo-controlled, parallel-group, multicenter trial, 152 adults diagnosed with a malignant, solid tumor with metastases to bone were randomized to flexible-dose pregabalin (100, 150, 300, or 600 mg/day) or placebo, as add-on to stable opioid analgesic therapy, which was optimized prior to the start of the study. The primary efficacy endpoint was the duration-adjusted average change (DAAC) from baseline in the daily worst pain at the reference site (measured by 11-point numeric rating scale [NRS]) during the fixed-dosage phase. The study was terminated early following an interim analysis that indicated an increase in sample size would be needed to satisfy statistical assumptions for the primary endpoint. Given the early termination of the study, only descriptive analyses were performed.

Results

The mean (standard deviation) DAAC from baseline in NRS score for the primary endpoint favored pregabalin treatment: −1.53 (1.81) in the pregabalin group and −1.23 (1.74) in the placebo group. Mean DAAC for average pain and sleep interference (NRS) also favored pregabalin. More patients treated with pregabalin reported improvement (“very much improved,” “much improved,” or “minimally improved”) based on Patient Global Impression of Change: 81.4% compared with 70.0% in the placebo group.

Conclusion

Data from this study indicate that pregabalin use may reduce metastatic bone pain. Due to the incomplete analysis, further study of pregabalin in the management of CIBP is required.