Duloxetine for the treatment of fibromyalgia

Aripiprazole: The antiallodynic and antihyperalgesic effects in chronic constriction injury-induced neuropathic pain and reserpine-induced fibromyalgia with possible mechanisms

Neuropathic pain, caused by peripheral or central nerve damage, and fibromyalgia, a chronic musculoskeletal disorder, require complex treatment approaches. This study evaluated the antiallodynic and antihyperalgesic effects of aripiprazole (1, 5, and 10 mg/kg, i. p.) in rats with chronic constriction injury-induced neuropathic pain and reserpine-induced fibromyalgia in female Sprague-Dawley rats, using electronic von Frey and Hargreaves tests. Dopaminergic, serotonergic, and opioidergic systems' roles were assessed through pre-treatment with sulpiride (50 mg/kg), WAY 100635 (1 mg/kg), and naloxone (1 mg/kg), respectively. The effect of aripiprazole was compared with 30 mg/kg pregabalin in the neuropathic pain model and 30 mg/kg duloxetine in the fibromyalgia model. Aripiprazole demonstrated significant antiallodynic and antihyperalgesic activity in both models. It did not change locomotor activity at a dose of 1 mg/kg but caused a decrease at a dose of 5 mg/kg. Dopamine D2, serotonin 5-HT1A, and opioidergic receptors contributed to aripiprazole's effects at varying levels. This study highlights the potential use of aripiprazole for managing neuropathic pain and fibromyalgia by targeting multiple receptor systems. The findings demonstrate the potential use of aripiprazole alone or as an adjuvant in the treatments of neuropathic pain and fibromyalgia.

Efficacy of Low-Dose Naltrexone in Treating Patients with Fibromyalgia: systematic Review and Meta-Analysis

Low-dose naltrexone (LDN) has demonstrated mixed efficacy in treating fibromyalgia. This systematic review and meta-analysis aimed to evaluate the efficacy of LDN for fibromyalgia. We systematically searched electronic databases and gray literature from inception to May 2024. Included studies were clinical trials in humans published in English, reporting mean changes in pain scores and fibromyalgia symptom severity, comparing baseline to endpoint and LDN to placebo. Of 575 identified articles, eight met the eligibility criteria. In the LDN group, the Standardized Mean Difference (SMD) for pain decreased by 1.03 (95% confidence interval (CI): -1.25, -0.80; I2 = 25%), and fibromyalgia symptom severity decreased by 1.02 (95% CI: -1.35, -0.69; I2 = 52%) post-LDN treatment compared to the baseline. However, no significant differences in mean change in pain (SMD -0.50, 95% CI: -1.19, 0.19; I2 = 91%) and fibromyalgia symptoms severity scores (SMD -0.67, 95% CI: -1.67, 0.34; I2 = 95%) were observed between the LDN and placebo groups. Although LDN marginally reduced pain and symptom severity from baseline, these effects were not superior to placebo. This suggests that LDN may not provide significant clinical benefit over placebo in fibromyalgia management, warranting further research.

Clinical side-effects based drug repositioning for anti-epileptic activity

Several generations of anti-epileptic drugs (AEDs) are available but have several associated side effects apart from a limited success rate. Drug repositioning strategies have gained importance in the last two decades owing to lower failure rates and economic burden. Drugs with similar side effect profiles may share a common mechanism of action and thus can be linked to other disease treatments. The present study was carried out to identify the newly approved drug candidate(s) as AEDs using clinical side-effects drug repositioning strategy. The clinical side effect similarity of drugs available in the SIDER v4.1 database was estimated against common side effects of 5 major marketed AEDs, using the 'dplyr' package library in the R. Further drugs were filtered based on Blood Brain Barrier permeability prediction and FDA-approval status. Molecular docking studies were performed for selected 26 hits (drugs) against previously identified epilepsy target receptors: Voltage-gated sodium channel α2 (Nav1.2), GABA receptor α1-β1 (GABAr α1-β1), and Voltage-gated calcium channel α-1 G (Cav3.1). Only 2 drugs (Ziprasidone and Paroxetine) showed better binding affinities against studied epilepsy receptors Nav1.2, GABAr α1-β1, and Cav3.1, than their corresponding standard AEDs, i.e. Carbamazepine, Clonazepam, and Pregabalin, respectively. Ziprasidone reportedly showed seizure-like symptoms in ∼3% of patients and was hence omitted from further study. The MDS study of docked complexes of Paroxetine with selected epilepsy target receptors showed stable RMSD values and better interaction energies. The study reveals Paroxetine as a potential candidate to be repurposed for 1st line epileptic seizure medication.Communicated by Ramaswamy H. Sarma.

Pain associated with breast cancer: etiologies and therapies

Pain associated with breast cancer is a prevalent problem that negatively affects quality of life. Breast cancer pain is not limited to the disease course itself but is also induced by current therapeutic strategies. This, combined with the increasing number of patients living with breast cancer, make pain management for breast cancer patients an increasingly important area of research. This narrative review presents a summary of pain associated with breast cancer, including pain related to the cancer disease process itself and pain associated with current therapeutic modalities including radiation, chemotherapy, immunotherapy, and surgery. Current pain management techniques, their limitations, and novel analgesic strategies are also discussed.

How durable are the effects of cognitive-behavioural therapy‎ in controlling fibromyalgia symptoms? A prospective cohort study

PURPOSE

Cognitive-behavioural therapy (CBT) is widely used for the treatment of fibromyalgia. However, there is no consensus on the durability of its effects on these patients. In this study, we evaluated how durable are the effects of CBT in controlling fibromyalgia symptoms.

METHODS

Forty-eight fibromyalgia patients treated with traditional face-to-face CBT were included. CBT was performed in 20 consecutive group sessions. To evaluate the durability of treatment, the effects of CBT on fibromyalgia symptoms were checked at five time-points: before the CBT, immediately after the CBT, 3 months after the CBT, 6 months after the CBT, and 12 months after the CBT. Outcome measures were the Fibromyalgia impact questionnaire (FIQ) and widespread pain index (WPI).

RESULTS

The mean FIQ score of the patients was 68.3 ± 18.8 before the CBT and 50.5 ± 14.1 1 week after the CBT (p < 0.001). The mean post-CBT FIQ score did not significantly change three and 6 months after the CBT (p = 0.11 and p = 0.09, respectively) while the positive effects of CBT significantly diminished after 12 months (p < 0.001). The mean WPI was 10.4 ± 3.6 before the CBT and 8.6 ± 3.1 1 week after the end of CBT (p < 0.001). The mean WPI of three and 6 months was not statistically different from that immediately after the CBT (p = 0.18 and p = 0.15, respectively), while after 12 months, it significantly worsened (p < 0.001).

CONCLUSION

CBT's beneficial effects for fibromyalgia patients are durable for 6 months. Complementary CBT sessions could be implemented to boost the CBT effect after this period.

Duloxetine for fibromyalgia syndrome: a systematic review and meta-analysis

INTRODUCTION

The optimal dose of duloxetine in the management of fibromyalgia remains still controversial. Therefore, a systematic review and meta-analysis to investigate efficacy and safety of duloxetine was conducted. The outcomes of interests were to assess changes in Fibromyalgia Impact Questionnaire (FIQ), Brief Pain Inventory (BPI), and Clinical Global Impression (CGI). The rate of of adverse events and those leading to therapy discontinuation were also investigated.

MATERIAL AND METHODS

This study followed the 2020 PRISMA guidelines. The literature search started in December 2022 accessing PubMed, Google scholar, Embase, and Scopus databases. All the RCTs investigating the efficacy and safety of daily administration of duloxetine for fibromyalgia were accessed. Studies reporting quantitative data under the outcomes of interest, and including a minimum of 10 patients who completed a minimum of 4 weeks follow-up, were included. Studies on combined pharmacological and non-pharmacological managements for fibromyalgia were not considered.

RESULTS

Data from 3432 patients (11 RCTs) were included. The mean age of the patients was 46.4 ± 10.7 years old, and the mean BMI 25.3 ± 3.2 kg/m². 90% (3089 of 3432 patients) were women. The 60 mg/daily cohort reported the higher FIQ, followed by the 30, 30-60, 120 mg/daily, and placebo groups, while the 60-120 mg /daily group performed the worst results. Concerning the CGI severity scale, placebo resulted in the lowest improvement, and no differences were found in the other groups. Concerning the BPI interference and severity pain scores, the 30-60 mg/daily group reported the worst result, along with the placebo group. The rate of adverse events leading to study discontinuation were lower in the 60-120 group, followed by the 30-60 and 30 mag/daily groups. Duloxetine was superior in all the comparisons to placebo, irrespective of the doses, in all endpoints analysed.

CONCLUSIONS

Duloxetine could help in improving symptoms of fibromyalgia. The dose of duloxetine should be customised according to individual patients. Irrespective of the doses, duloxetine was more effective than placebo in the management of fibromyalgia. The dose of duloxetine must be customised according to individual patients. Level of evidence I Meta-analysis of double-blind RCTs.

The analgesic effect and safety of duloxetine in total knee arthroplasty: A systematic review

Background: Duloxetine is a serotonin and norepinephrine reuptake inhibitor (SNRI) with clinical efficacy in chronic pain conditions. In this study, we aim to evaluate the analgesic effect and safety of duloxetine in total knee arthroplasty (TKA). Methods: A systematic search was completed on MEDLINE, PsycINFO, and Embase from inception to December 2022 to find relevant articles. We used Cochrane methodology to evaluate the bias of included studies. Investigated outcomes included postoperative pain, opioid consumption, adverse events (AEs), range of motion (ROM), emotional and physical function, patient satisfaction, patient-controlled analgesia (PCA), knee-specific outcomes, wound complications, skin temperature, inflammatory markers, length of stay, and incidence of manipulations. Results: Nine articles involving 942 participants were included in our systematic review. Out of nine papers, eight were randomized clinical trials and one was a retrospective study. The results of these studies indicated the analgesic effect of duloxetine on postoperative pain, which was measured using numeric rating scale and visual analogue scale. Deluxetine was also effective in reducing the morphine requirement and wound complications and enhancing patient satisfaction after surgery. However, the results on ROM, PCA, and knee-specific outcomes were contraventional. Deluxetine was generally safe without serious AEs. The most common AEs included headache, nausea, vomiting, dry mouth, and constipation. Conclusion: Duloxetine may be an effective treatment option for postoperative pain following TKA, but further rigorously designed and well-controlled randomized trials are required.

Recent Developments in Pharmacotherapy of Depression: Bench to Bedside

For the last 70 years, we did not move beyond the monoamine hypothesis of depression until the approval of the S-enantiomer of ketamine, an N-methyl-D-aspartate (NMDA) receptor blocker and the first non-monoaminergic antidepressant characterized by rapid antidepressant and antisuicidal effects. A similar profile has been reported with another NMDA receptor antagonist, dextromethorphan, which has also been approved to manage depression in combination with bupropion. More recently, the approval of a positive allosteric modulator of GABA-A receptors, brexanolone, has added to the list of recent breakthroughs with the relatively rapid onset of antidepressant efficacy. However, multiple factors have compromised the clinical utility of these exciting discoveries in the general population, including high drug acquisition costs, mandatory monitoring requirements, parenteral drug administration, lack of insurance coverage, indirect COVID-19 effects on healthcare systems, and training gaps in psychopharmacology. This narrative review aims to analyze the clinical pharmacology of recently approved antidepressants and discuss potential barriers to the bench-to-bedside transfer of knowledge and clinical application of exciting recent discoveries. Overall, clinically meaningful advances in the treatment of depression have not reached a large proportion of depressed patients, including those with treatment-resistant depression, who might benefit the most from the novel antidepressants.

MAPK Pathways in Ocular Pathophysiology: Potential Therapeutic Drugs and Challenges

Mitogen-activated protein kinase (MAPK) pathways represent ubiquitous cellular signal transduction pathways that regulate all aspects of life and are frequently altered in disease. Once activated through phosphorylation, these MAPKs in turn phosphorylate and activate transcription factors present either in the cytoplasm or in the nucleus, leading to the expression of target genes and, as a consequence, they elicit various biological responses. The aim of this work is to provide a comprehensive review focusing on the roles of MAPK signaling pathways in ocular pathophysiology and the potential to influence these for the treatment of eye diseases. We summarize the current knowledge of identified MAPK-targeting compounds in the context of ocular diseases such as macular degeneration, cataract, glaucoma and keratopathy, but also in rare ocular diseases where the cell differentiation, proliferation or migration are defective. Potential therapeutic interventions are also discussed. Additionally, we discuss challenges in overcoming the reported eye toxicity of some MAPK inhibitors.

Pharmacological Interaction of Quercetin Derivatives of Tilia americana and Clinical Drugs in Experimental Fibromyalgia

Fibromyalgia (FM) is a pain syndrome characterized by chronic widespread pain and CNS comorbidities. Tilia americana var. mexicana is a medicinal species used to treat anxiety, insomnia, and acute or chronic pain. However, its spectrum of analgesic efficacy for dysfunctional pain is unknown. To investigate a possible therapeutic alternative for FM-type pain, an aqueous Tilia extract (TE) and its flavonoid fraction (FF) containing rutin and isoquercitrin were evaluated alone and/or combined with clinical drugs (tramadol—TRA and pramipexol—PRA) using the reserpine-induced FM model in rats. Chromatographic analysis allowed the characterization of flavonoids, while a histological analysis confirmed their presence in the brain. TE (10–100 mg/kg, i.p.) and FF (10–300 mg/kg, i.p.) produced significant and dose-dependent antihyperalgesic and antiallodynic effects equivalent to TRA (3–10 mg/kg, i.p.) or PRA (0.01–1 mg/kg, s.c.). Nevertheless, the combination of FF + TRA or FF + PRA resulted in an antagonistic interaction by possible competitive action on the serotonin transporter or µ-opioid and D₂ receptors, respectively, according to the in silico analysis. Flavonoids were identified in cerebral regions because of their self-epifluorescence. In conclusion, Tilia possesses potential properties to relieve FM-type pain. However, the consumption of this plant or flavonoids such as quercetin derivatives in combination with analgesic drugs might reduce their individual benefits.

Pain severity and pain interference during major depressive episodes treated with escitalopram and aripiprazole adjunctive therapy: a CAN-BIND-1 report

Escitalopram may have pain-alleviating effects for patients with comorbid pain and depression. This study aimed to quantify improvements in pain for patients on escitalopram and adjunctive aripiprazole. A secondary analysis of the CAN-BIND-1 trial was conducted which only included participants with a current depressive episode and pain. Participants received escitalopram (10-20mg) for eight weeks and treatment response was defined as a reduction in Montgomery-Åsberg Depression Rating Scale (MADRS) of at least 50% from baseline. Non-responders at week 8 received adjunctive aripiprazole (2-10mg) for another eight weeks. The Brief Pain Inventory's pain severity (PSC) and pain interference (PIC) composite scores were measured at baseline, week 8, and week 16. Linear regression was used to determine how PSC and PIC differed between treatment responders and non-responders. Eighty-two participants with pain and depression received escitalopram. PSC and PIC decreased significantly regardless of treatment response at week 8, although responders had significantly lower PSC and PIC than non-responders. For the group receiving aripiprazole after week 8, neither PSC nor PIC improved further. Further research is needed to identify interventions that might treat both pain and depression symptoms.

The P2X4 Receptor: Cellular and Molecular Characteristics of a Promising Neuroinflammatory Target

The adenosine 5′-triphosphate-gated P2X4 receptor channel is a promising target in neuroinflammatory disorders, but the ability to effectively target these receptors in models of neuroinflammation has presented a constant challenge. As such, the exact role of P2X4 receptors and their cell signalling mechanisms in human physiology and pathophysiology still requires further elucidation. To this end, research into the molecular mechanisms of P2X4 receptor activation, modulation, and inhibition has continued to gain momentum in an attempt to further describe the role of P2X4 receptors in neuroinflammation and other disease settings. Here we provide an overview of the current understanding of the P2X4 receptor, including its expression and function in cells involved in neuroinflammatory signalling. We discuss the pharmacology of P2X4 receptors and provide an overview of P2X4-targeting molecules, including agonists, positive allosteric modulators, and antagonists. Finally, we discuss the use of P2X4 receptor modulators and antagonists in models of neuroinflammatory cell signalling and disease.

Managing Bipolar Disease Complicated with Psychosis in Conjunction with Polypharmacy, Parkinson’s Disease, and Multiple Comorbidities

The lifelong prevalence of bipolar disorder in adults, including subsyndromal forms, has increased over the years in the United States. By contrast, neurodegenerative diseases such as Parkinson’s disease have demonstrated an age-related rise in prevalence. As the global population manages to live longer thanks to sociomedical developments, it is expected to observe a rise in the occurrence of comorbid neuropsychiatric disorders. Herein, we present the case and management regimen of a 51-year-old female patient with multiple comorbidities and in the presence of polypharmacy. She was diagnosed with Parkinson’s disease and bipolar disorder type I alongside multiple comorbidities; her polypharmacy and medical history presented a significant clinical challenge in managing her condition. This case report focuses on the pharmacologic management of neuropsychiatric disorders titrated to this patient’s particular needs, which were complicated by psychosis and comorbidities.

Fibromyalgia: Recent Advances in Diagnosis, Classification, Pharmacotherapy and Alternative Remedies

Fibromyalgia (FM) is a syndrome that does not present a well-defined underlying organic disease. FM is a condition which has been associated with diseases such as infections, diabetes, psychiatric or neurological disorders, rheumatic pathologies, and is a disorder that rather than diagnosis of exclusion requires positive diagnosis. A multidimensional approach is required for the management of FM, including pain management, pharmacological therapies, behavioral therapy, patient education, and exercise. The purpose of this review is to summarize the recent advances in classification criteria and diagnostic criteria for FM as well as to explore pharmacotherapy and the use of alternative therapies including the use of plant bioactive molecules.

Genomic Medicine: Lessons Learned From Monogenic and Complex Bone Disorders

Current genetic studies of monogenic and complex bone diseases have broadened our understanding of disease pathophysiology, highlighting the need for medical interventions and treatments tailored to the characteristics of patients. As genomic research progresses, novel insights into the molecular mechanisms are starting to provide support to clinical decision-making; now offering ample opportunities for disease screening, diagnosis, prognosis and treatment. Drug targets holding mechanisms with genetic support are more likely to be successful. Therefore, implementing genetic information to the drug development process and a molecular redefinition of skeletal disease can help overcoming current shortcomings in pharmaceutical research, including failed attempts and appalling costs. This review summarizes the achievements of genetic studies in the bone field and their application to clinical care, illustrating the imminent advent of the genomic medicine era.

Targeting Pathological Tau by Small Molecule Inhibition of the Poly(A):MSUT2 RNA-Protein Interaction

Neurofibrillary tangles composed of aberrantly aggregating tau protein are a hallmark of Alzheimer's disease and related dementia disorders. Recent work has shown that mammalian suppressor of tauopathy 2 (MSUT2), also named ZC3H14 (Zinc Finger CCCH-Type Containing 14), controls accumulation of pathological tau in cultured human cells and mice. Knocking out MSUT2 protects neurons from neurodegenerative tauopathy and preserves learning and memory. MSUT2 protein functions to bind polyadenosine [poly(A)] tails of mRNA through its C-terminal CCCH type zinc finger domains, and loss of CCCH domain function suppresses tauopathy in Caenorhabditis elegans and mice. Thus, we hypothesized that inhibiting the poly(A):MSUT2 RNA-protein interaction would ameliorate pathological tau accumulation. Here we present a high-throughput screening method for the identification of small molecules inhibiting the poly(A):MSUT2 RNA-protein interaction. We employed a fluorescent polarization assay for initial small molecule discovery with the intention to repurpose hits identified from the NIH Clinical Collection (NIHCC). Our drug repurposing development workflow included validation of hits by dose-response analysis, specificity testing, orthogonal assays of activity, and cytotoxicity. Validated compounds passing through this screening funnel will be evaluated for translational effectiveness in future studies. This preclinical drug development pipeline identified diverse FDA approved drugs duloxetine, saquinavir, and clofazimine as potential repurposing candidates for reducing pathological tau accumulation.

The effect of cognitive behavioral therapy on the circulating proinflammatory cytokines of fibromyalgia patients: A pilot controlled clinical trial

OBJECTIVES

There is no consensus over the effect size of cognitive behavioral therapy (CBT) in the treatment of fibromyalgia (FM). This study aims to evaluate the effect of CBT on FM patients, through assessing circulating proinflammatory cytokines.

METHODS

A controlled, single-blind, parallel clinical trial was performed with 21 FM patients in each group. Sixteen FM patients in the intervention group (CBT) and 17 FM patients in the control group (waiting-list) completed the study. For the intervention group, traditional face-to-face CBT was performed for groups of 10 and 11 patients in 20 sessions. Fibromyalgia Impact Questionnaire (FIQ), widespread pain index (WPI), circulating IL-6, IL-8, and TNF-α level were evaluated before and after the intervention using enzyme-linked immunosorbent assay. Intention-to-treat analysis was performed as the primary analysis.

RESULTS

The average changes of factors examined were as follows: FIQ score -0.61 ± 5.5 in the waiting-list group and 10.2 ± 14.9 in the CBT group (p = 0.012); WPI -0.33 ± 1.1 in the waiting-list group and 2.4 ± 3.1 in the CBT group (p = 0.002); serum IL-6 level -0.05 ± 0.86 pg/ml in the waiting-list group and 1.5 ± 2.4 pg/ml in the CBT group (p = 0.002); serum IL-8 level - 0.55 ± 0.2.5 pg/ml in the waiting-list group and 5 ± 5.9 pg/ml in the CBT group (p = 0.002); serum TNF-α level 0.67 ± 1.8 pg/ml in the waiting-list group and 0.7 ± 1.6 pg/ml in the CBT group (p = 0.89).

CONCLUSION

Reductions in proinflammatory cytokines after CBT compared with a waiting-list control group confirm the potential value of these biomarkers as surrogate outcome measures in FM.

Risk for Medication Nonadherence Among Medicaid Enrollees With Fibromyalgia: Development of a Validated Risk Prediction Tool

OBJECTIVE

To develop and validate a risk assessment tool called the Prescription Medication Non-Adherence Prediction Tool (Rx-NAPT) to predict medication nonadherence in patients with fibromyalgia.

METHODS

This was a retrospective cohort study using claims data from South Carolina Medicaid. Patients with fibromyalgia who were ≥18 years old and who had filled at least 1 prescription medication for pregabalin, duloxetine, or milnacipran from January 1, 2005, through June 30, 2011 were included. Medication possession ratios (MPRs) were calculated to classify patients as adherent (MPR ≥ 80%) or nonadherent (MPR < 80%). Multivariable logistic models using 100 bootstrap replications (with replacement) were used to identify factors associated with medication nonadherence, including age, gender, race, days' supply, medication type, and fibromyalgia-related comorbidity score. Weighted β coefficients of the predictors were used to create the Rx-NAPT. Youden's J statistic was used to classify nonadherent patients into different levels of risk.

RESULTS

The study sample comprised 6,626 patients with fibromyalgia, where 4,804 (72.50%) were non-adherent and 1,822 (27.50%) were adherent to their prescribed medication(s). Logistic regression models showed that 7 predictors (gender, age, race, fibromyalgia-related comorbidity score, medication type, health maintenance organization coverage, emergency room visit) were statistically significant in ≥50% of the bootstrapped samples. The final model demonstrated reasonable discrimination (area under the curve [AUC] = 0.6224) and calibration (Hosmer-Lemeshow goodness-of-fit; P > 0.05) statistics and was validated internally (AUC = 0.6372).

CONCLUSION

Poor adherence with medication remains an important barrier to providing optimal care. Our risk prediction model provides an easy tool to help clinicians better identify patients with fibromyalgia who may not take their medications as prescribed.

Attentional performance may help to identify duloxetine responders in chronic pain fibromyalgia patients

BACKGROUND

Long-term pain affects brain in response to attention tasks. This study aimed to verify the relationship between performance in a computerized visual attention test (CVAT) and response to duloxetine in fibromyalgia patients. Duloxetine is approved for the treatment but the response is not immediate.

METHODS

Patients were drawn from a sample of 74 patients with chronic pain. These patients were selected because they kept their subjective perceptions of pain as severe after 1 week of duloxetine treatment. All patients were tested in the CVAT on two occasions: the first appointment and 7 days after starting duloxetine.

RESULTS

After 6 weeks, the group was subdivided into responsive and non-responsive patients. Responsiveness was defined by a subjective improvement from severe to low-intensity or no-pain after the sixth week of duloxetine treatment. Responsive patients showed objective attentional improvements in the second test. Non-respondent patients did not exhibit changes in attentional performance in the second test as compared to the first one.

CONCLUSIONS

The data were interpreted considering that persistent pain in fibromyalgia is maintained by central sensitization that may be associated with functional changes in the dorsolateral prefrontal cortex and the posterior parietal cortex. In responsive patients, duloxetine treatment may be responsible for a partial recovery of these regions. This may explain the early attentional improvement observed in the responsive patients after 1 week of treatment. Thus, attentional performance may help to predict which patients will respond to duloxetine treatment even before they can demonstrate subjective improvements in pain perception.

SIGNIFICANCE

This study shows that an improvement in an attentional test is a reliable predictor of the treatment response even without any improvement in the perception of pain.

Polypharmacy, Opioid Use, and Fibromyalgia: A Secondary Analysis of Clinical Trial Data

The major therapeutic approach for treating fibromyalgia (FM), a chronic widespread pain syndrome, is pharmacotherapy-centered symptom management. Complexity of treatment often leads to multiple medication prescriptions. While there is no current alternative to the probable need for polypharmacy in this patient population, there remains concern related to potential side effects and adverse drug events. In this secondary analysis of data on medications taken collected from two parent studies, all medications were broken down into the following categories: opioid, nonopioid, antidepressant, anticonvulsant, muscle relaxant, and benzodiazepine. The impact on pain severity and pain interference of these medication categories as well as perceived stress, fatigue, and depression scores was assessed. Baseline pain severity ( p = .0106) and pain interference ( p = .0002) were significantly correlated with opioid use as compared to nonopioid use. A multivariate regression with backward elimination resulted in a model for pain severity with one significant predictor variable, fatigue ( p < .0001); pain interference had three significant predictor variables: opioid use ( p = .04), fatigue ( p < .0001), and depression ( p = .04). While future studies should further address the utility of opioids and examine the role of polypharmacy as part of symptom management strategies for individuals with FM, study findings suggest that, for those who suffer chronic widespread pain as the predominant symptom experience, a challenge equally as perplexing for nurses and nursing research alike as managing the pain lies in addressing the fatigue and depression in this patient population.

Polyelectrolyte Hydrogel Platforms for the Delivery of Antidepressant Drugs

Some vinyl hydrogels containing α-amino acid residues (l-phenylalanine, l-valine) were used as polyelectrolyte platforms for the evaluation of the controlled release of two antidepressants (paroxetine and duloxetine). The closer acidity constant (pKa) values of the two drugs show a closer release profile in physiological phosphate buffered saline (PBS) buffer (pH 7.40) and for long periods of time. The great electrostatic interaction forces between the COO- group of the hydrogel and the protonated secondary amino nitrogen of the drug are the main factor improving the release kinetics; this release was found to be slower compared to that of two structurally related drugs bearing the tertiary amino nitrogen atom (citalopram and trazodone). Moreover, at the lower value of pH 4.60, paroxetine showed a flatter release profile from the hydrogel containing the l-phenylalanine residues that, after six days, is half of that shown by duloxetine. Further effects due to steric and hydrophobic interactions may contribute to the different release profile. A further stimulation with alternating magnetic fields (AMF) of low frequency (20 kHz/50 W) enhanced the release of the drug at pH 7.40 from the hydrogel containing magnetic nanoparticles. Both AMF and PBS solution at pH 7.40 were used to trigger the 'on-demand' pulsatile paroxetine release from the nanocomposite hydrogel.

The search for novel analgesics: targets and mechanisms

The management of the pain state is of great therapeutic relevance to virtually every medical specialty. Failure to manage its expression has deleterious consequence to the well-being of the organism. An understanding of the complex biology of the mechanisms underlying the processing of nociceptive information provides an important pathway towards development of novel and robust therapeutics. Importantly, preclinical models have been of considerable use in determining the linkage between mechanism and the associated behaviorally defined pain state. This review seeks to provide an overview of current thinking targeting pain biology, the use of preclinical models and the development of novel pain therapeutics. Issues pertinent to the strengths and weaknesses of current development strategies for analgesics are considered.

Pain management in the elderly

Persistent pain in older adults is common, and associated with substantial morbidity. Optimal management starts with assessment, including pain presence, intensity, characteristics, and interference; painful conditions; pain behaviors; pain-related morbidity; pain treatments; and coping style. Treatment incorporates analgesics demonstrated to decrease pain and improve a patient's sense of well-being. The World Health Organization's 3-step pain ladder is widely accepted and adopted for selecting analgesics among patients with non-cancer pain. Shared decision making is essential to balance the benefits and burdens of analgesics. This article reviews pain assessment/management for older adults, focusing on commonly used analgesics.

Widespread pain in temporomandibular disorders

SUMMARY Chronic widespread pain (CWP) represents pain involving several regions of the body. Various psychological and social risk factors such as poor general health status, sleep disturbance, fatigue and high psychological distress have been identified for the development of CWP. Numerous chronic pain conditions are comorbid, resulting in the development of CWP in many of these patients. Temporomandibular disorder is one of the most extensively studied chronic musculoskeletal pain condition in terms of its comorbidity with CWP and fibromyalgia. It has been proposed that these comorbid pain disorders share common denominators, including exposure to certain environmental events, elevated psychological distress, pain amplification and genetic predisposition. Increased awareness of CWP is important for improved diagnoses and more effective pain management. Patients with CWP can be effectively managed in multidisciplinary pain clinics.

Predictors of duloxetine adherence and persistence in patients with fibromyalgia

OBJECTIVES

Adherence to medication for the treatment of fibromyalgia (FM) is predictive of lower overall health-care costs, and thus a lower burden on both patients and providers. The objectives of this study were to examine the predictors of adherence to and persistence with duloxetine therapy among commercially insured FM patients, and to identify subgroups of patients with high duloxetine persistence and adherence.

STUDY DESIGN

This cross-sectional, retrospective study analyzed medical and pharmacy records over 1 year for patients in the US aged 18-64 years with FM who initiated (no prior 90-day use) duloxetine treatment in 2008.

METHODS

Adherence to duloxetine was measured by medication possession ratio (MPR), with high adherence defined as MPR ≥ 0.8. Persistence was defined as the duration of therapy from the index date to the earliest of: the ending date of the last prescription, the date of the first gap of >15 days between prescriptions, or the end of the study period (12 months). Demographic and clinical predictors of adherence were examined via multiple logistic regression (MLR), and subgroups of duloxetine-persistent and -adherent patients were identified using classification and regression trees (CART).

RESULTS

Among 4660 duloxetine patients, 33% achieved high adherence. Factors associated with high adherence from MLR included older age, North Central and Northeast regions, prior venlafaxine, pregabalin, selective serotonin reuptake inhibitor (SSRI), or other antidepressant use, or comorbid dyslipidemia or osteoarthritis (all P < 0.05). CART analysis revealed that patients with prior antidepressant use, aged ≥46, or prior osteoarthritis had higher MPR (all P < 0.05), and patients aged ≥45 with a history of SSRI, venlafaxine, or anticonvulsant use had longer duration of therapy (all P < 0.05).

CONCLUSIONS

Patients with high adherence to and persistence with duloxetine were significantly older and had prior antidepressant use.