Survey of European patients assessing their own noncancer chronic pain: results from Spain

The Prevalence of Chronic Pain in the Adult Population in Israel: An Internet-Based Survey

Background. Chronic pain (CP) prevalence in different studies has been inconsistent, ranging from 12% in Spain to 42% in the UK. Purpose. We conducted an internet-based survey in a representative cohort of Israeli adults assembled by a large professional survey company in order to probe the prevalence of CP in Israel. Methods. 8,300 Israeli adults comprising a representative cohort of the Israeli population were asked whether they were suffering from pain lasting over 3 months. 1647 participants responded (19.8% response rate). Of these, 515 (31.3%) had CP. Participants with CP were then asked a series of follow-up questions regarding their chronic pain. Statistical weights were used to correct for the distribution of the Israeli population based on sociodemographic characteristics. Results. CP patients were significantly older than respondents without pain. The average daily pain was 5.8/10 on a numerical rating scale. Common pain locations were axial skeleton and headaches. However, over half of patients reported pain in multiple body areas, and around a fifth had an undiagnosed chronic pain syndrome. Around 40% of pain patients reported to have visited a specialized pain clinic, and the same proportion has consulted several specialists. Despite this, a sizable proportion of high pain intensity patients were still left with no or inefficient treatment to alleviate their pain. Conclusions. This is the first internet survey conducted in Israel to estimate the incidence of CP, and the high CP prevalence documented is in agreement with previous reports from Europe and the USA. It also reaffirms the widespread existence of multifocal or widespread pain in clinical chronic pain and the correlation between pain intensity, impact on patients’ quality of life and disability, and pain intractability. These data reaffirm the similarly major health burden CP presents across different countries and cultures.

Management of Chronic Low Back Pain and the Impact on Patients’ Personal and Professional Lives: Results From an International Patient Survey

Objective

Methods

Results

Conclusion

Prevalence of Therapeutic use of Opioids in Chronic non-Cancer Pain Patients and Associated Factors: A Systematic Review and Meta-Analysis

Objectives: To determine the prevalence and factors associated with the use of opioids among patients with chronic non-cancer pain (CNCP).

Methods: A systematic review and meta-analysis. Comprehensive literature searches in Medline-PubMed, Embase and SCOPUS databases. Original studies published between 2009 and 2019 with a cross-sectional design were included. The quality of the studies was assessed with Critical Appraisal Checklist for Studies Reporting Prevalence Data from the Joanna Briggs Institute. Protocol registered in the International Prospective Register of Systematic Reviews with reference number: CRD42019137990.

Results: Out of the 1,310 potential studies found, 25 studies fulfilled the inclusion criteria. Most of the studies were of high quality. High levels of heterogeneity were found in the studies included. In the general population, the prevalence of long-term opioid use was 2.3% (95% CI: 1.5–3.6%), the prevalence of short-term opioid use was 8.1% (95% CI: 5.6–11.6%), and among people with chronic low back pain it was 5.8% (95% CI: 0.5–45.5%). The prevalence of opioid use among patients from the health records or medical surveys was 41% (95% CI: 23.3–61.3%). Finally, in patients with musculoskeletal pain, the prevalence was 20.5% (95% CI: 12.9–30.9%) and in patients with fibromyalgia, 24.5% (95% CI: 22.9–26.2%). A higher prevalence of opioid use was observed among men, younger people, patients receiving prescriptions of different types of drugs, smokers and patients without insurance or with noncommercial insurance. In addition, non-white and Asian patients were less likely to receive opioids than non-Hispanic white patients.

Conclusions: The prevalence of opioid use among patients with CNCP was higher in subjects with short or occasional use compared to those with long-term use. Men, younger people, more chronic pain conditions, and patients without insurance or with noncommercial insurance were most related to opioid use. However, non-white and Asian patients, and those treated by a physician trained in complementary medicine were less likely to use opioids.

What proportion of patients with chronic noncancer pain are prescribed an opioid medicine? Systematic review and meta-regression of observational studies

Guidelines now discourage opioid analgesics for chronic noncancer pain because the benefits frequently do not outweigh the harms. We aimed to determine the proportion of patients with chronic noncancer pain who are prescribed an opioid, the types prescribed and factors associated with prescribing. Database searches were conducted from inception to 29 October 2018 without language restrictions. We included observational studies of adults with chronic noncancer pain measuring opioid prescribing. Opioids were categorized as weak (e.g. codeine) or strong (e.g. oxycodone). Study quality was assessed using a risk of bias tool designed for observational studies measuring prevalence. Individual study results were pooled using a random-effects model. Meta-regression investigated study-level factors associated with prescribing (e.g. sampling year, geographic region as per World Health Organization). The overall evidence quality was assessed using Grading of Recommendations Assessment, Development and Evaluation criteria. Of the 42 studies (5,059,098 participants) identified, the majority (n = 28) were from the United States of America. Eleven studies were at low risk of bias. The pooled estimate of the proportion of patients with chronic noncancer pain prescribed opioids was 30.7% (95% CI 28.7% to 32.7%, n = 42 studies, moderate-quality evidence). Strong opioids were more frequently prescribed than weak (18.4% (95% CI 16.0-21.0%, n = 15 studies, low-quality evidence), versus 8.5% (95% CI 7.2-9.9%, n = 15 studies, low-quality evidence)). Meta-regression determined that opioid prescribing was associated with year of sampling (more prescribing in recent years) (P = 0.014) and not geographic region (P = 0.056). Opioid prescribing for patients with chronic noncancer pain is common and has increased over time.

Genetic Contribution in Low Back Pain: A Prospective Genetic Association Study

OBJECTIVES

Chronic pain is one of the most common reasons individuals seek medical attention. It is a major issue because of the wide interindividual variability in the analgesic response. This might be partly explained by the presence of variants in genes encoding molecules involved in pharmacodynamics and pharmacokinetics. The aim was to analyze opioid effectiveness in chronic low back pain (CLBP) relief after opioid titration, unveiling the impact of pharmacogenetics.

METHODS

The study included 231 opioid-naïve patients from the Spine Unit; age 63 ± 14 years, 64% female, body mass index 29 ± 6 kg/m² , visual analog scale pain intensity score 73 ± 16 mm. Clinical data were collected at baseline, 3 months after opioid titration, and after 2 to 4 years of follow-up concerning pain (intensity and relief), quality of life, disability, comorbidities, and drug prescription (opioid dose, rotations, and adverse events). The genotype influence of OPRM1, COMT, UGT2B7, ABCB1, KCNJ6, and CYP3A5*3A in analgesic response was analyzed by reverse-transcription polymerase chain reaction genotyping.

RESULTS

Patients with the COMT G472A-AA genotype (rs4680) and KCNJ6 A1032G-A allele (rs2070995) CLBP responded differently to opioid titration, with higher pain intensity requiring higher dosing. Furthermore, GG- genotypes of A118G (OPRM1, rs1799971) and A854G (UGT2B7, rs776746) influenced the neuropathic component. After opioid titration, CLBP intensity, neuropathic component, low back pain disability, anxiety, and depression significantly decreased, while quality of life improved.

CONCLUSION

Single-nucleotide polymorphisms in genes involved in pain transmission and opioid metabolism might predispose to exaggerated sensitivity and differences in the opioid analgesic effect in patients with CLBP. We encourage clinical trials for their clinical application in chronic pain management.

Use of multidomain management strategies by community dwelling adults with chronic pain: evidence from a systematic review

Background and aims Multidomain strategies (i.e. two or more strategies) for managing chronic pain are recommended to avoid excessive use of opioids while producing the best outcomes possible. The aims of this systematic review were to: 1) determine if patient-reported pain management is consistent with the use of multidomain strategies; and 2) identify the role of opioids and non-steroidal anti-inflammatory drugs (NSAIDs) in patient-reported pain management. Methods Bibliographic databases, websites, and reference lists of included studies were searched to identify published articles reporting community-based surveys of pain self-management from January 1989 to June 2017 using controlled vocabulary (and synonyms): pain; self-care; self-management; self-treatment; and adult. Two independent reviewers screened studies and extracted data on subject demographics, pain characteristics, pain self-management strategies, and pain outcomes. Pain self-management strategies were organized according to our conceptual model. Included studies were assessed for risk of bias. Differences between the researchers were resolved by consensus. Results From the 3,235 unique records identified, 18 studies published between 2002 and 2017 from 10 countries were included. Twenty-two types of pharmacological strategies were identified (16 prescription, six non-prescription). NSAIDs (15 studies, range of use 10-72%) and opioids (12 studies, range of use 5-72%) were the most commonly reported prescription pharmacological strategies. Other prescription pharmacological strategies included analgesics, acetaminophen, anticonvulsants, antidepressants, anxiolytics, salicylates, β-blockers and calcium channel blockers, disease-modifying anti-rheumatic drugs and steroids, muscle relaxants, topical products, triptans, and others. Twenty-two types of non-pharmacological strategies were identified: four medical strategies (10 studies), 10 physical strategies (15 studies), four psychological strategies (12 studies), and four self-initiated strategies (15 studies). Medical strategies included consulting a medical practitioner, chiropractic, and surgery. Physical strategies included exercise, massage, hot and cold modalities, acupuncture, physical therapy, transcutaneous electrical nerve stimulation, activity modification or restriction, assistive devices, and altering body position/posture. Psychological strategies included relaxation, prayer or meditation, therapy, and rest/sleep. Self-initiated strategies included dietary or herbal supplements, dietary modifications, and complementary and alternative medicine. Overall, the number of strategies reported among the studies ranged from five to 28 (out of 44 identified strategies). Limited data on pain outcomes was reported in 15 studies, and included satisfaction with pain management strategies, pain interference on daily activities, adverse events, lost work or restricted activity days, emergency department visits, and disabilities. Conclusions A wide variety and large number of pharmacological and non-pharmacological strategies to manage chronic pain were reported, consistent with the use of multidomain strategies. High levels of use of both NSAIDs and opioids also were reported. Implications Comprehensive review and consultation with patients about their pain management strategies is likely needed for optimal outcomes. Additional research is needed to determine: how many, when, and why multidomain strategies are used; the relationship between opioid use, multidomain management strategies, and level of pain; how multidomain strategies relate to outcomes; and if adding strategies to a pain management plan increases the risk of adverse events or interactions, and increases an individuals pain management burden.

Health benefits of an adverse events reporting system for chronic pain patients using long-term opioids

BACKGROUND

Safety data from long-term opioid therapy in the real world has been poorly studied in chronic non-cancer pain (CNCP). The aim was to design a pharmacovigilance data recording system and assess whether participation in this recording system improves pain management, enhancing patient's health status.

METHODS

A pharmacovigilance data recording system was conducted during 24 months. Data were self-reported by patients (pain, adverse events [AEs] and healthcare resources use) and physicians (morphine equivalent daily dose [MEDD] prescribed and suspected adverse drug reaction [ADRs]). Outcomes from patients with (case) or without (controls) suspected ADRs and cases follow-up were also compared with Spanish Pharmacovigilance System data.

RESULTS

A total of 753 patients were recruited in 897 visits. Fentanyl and tramadol were the most prescribed opioids, 89% with concomitant drugs, pregabalin being the one with the most potential drug interactions. Cases presented significantly higher pain intensity (VAS 67 ± 26 vs 59 ± 30 mm, P < 0.05), number of AEs (8 ± 6 vs 5 ± 3 AEs/patient, P < 0.01), polypharmacy related to pain (65% vs 34%, P < 0.01) and MEDD (139 ± 130 vs 106 ± 99 mg/d, P < 0.01) than controls. Furthermore, cases presented significant higher changes in pharmacological pain therapy due to pain, unplanned emergency visits and hospital admission than controls. Physicians notified 168 suspected ADRs mostly related to neurological or psychiatric events and 8% of them were previously unknown.

CONCLUSIONS

This data recording system provided important information to achieve a better control of CNCP pharmacological pain therapy, improving patient's health status and reducing costs to the Health System.

Xm2 Scores for Estimating Total Exposure to Multimodal Strategies Identified by Pharmacists for Managing Pain: Validity Testing and Clinical Relevance

Objective

To assess the validity of an exposure score obtained from the Xm² tool for all pharmacological and nonpharmacological strategies used by individuals to manage chronic pain.

Methods

Using data from individuals with chronic pain, eXposure multimodal (Xm²) scores were calculated by assigning one point for every 100 mg of morphine equivalent used (opioid medications); 25% of the maximum recommended exposure used (nonopioid medications); and any use of another strategy then summed. Content, criterion, construct, and convergent validity were assessed.

Results

The sample of 149 individuals used a mean of 12.6 (SD = 4.6) strategies to manage pain and had a mean Xm² score of 16.8 (SD = 9.1). Content validity was established by demonstrating that the pain management strategies identified were also reported in the literature. Criterion validity was established by the positive association of exposure scores with the following: interference with work (odds ratio (OR) = 2.23, 95% confidence interval (CI) = 1.14–4.36), daily activities (OR = 2.10, CI = 1.07–4.13), relationships (OR = 1.98, CI = 1.01–3.88), and leisure activities (OR = 2.31, CI = 1.18–4.50); workdays missed (OR = 5.10, CI = 1.92–13.58); emergency department visits (OR = 3.40, CI = 1.17–9.91); hospitalizations (OR = 4.18, CI = 0.86–20.37); and by a negative association with satisfaction (OR = 0.40, CI = 0.18–0.88). Construct validity was established by the positive association of exposure with baseline pain intensity (p < 0.01) and odds of experiencing an adverse event (OR = 2.31, CI = 1.18–4.52). Convergent validity was established through correlations of pain intensity from the Xm² score and existing quantitative analgesic questionnaire (QAQ) score.

Discussion

Xm² scores represent a valid estimate of total exposure to multimodal strategies used and provide clinically relevant information for deciding what strategies to use at what level.

Pharmacogenetics in Pain Treatment

Pain is an unpleasant feeling usually resulting from tissue damage that can persist along weeks, months, or even years after the injury, turning into pathological chronic pain, the leading cause of disability. Currently, pharmacology interventions are usually the first-line therapy but there is a highly variable analgesic drug response. Pharmacogenetics (PGx) offers a means to identify genetic biomarkers that can predict individual analgesic response opening doors to precision medicine. PGx analyze the way in which the presence of variations in the DNA sequence (single-nucleotide polymorphisms, SNPs) could be responsible for portions of the population reaching different levels of pain relief (phenotype) due to gene interference in the drug mechanism of action (pharmacodynamics) and/or its concentration at the place of action (pharmacokinetics). SNPs in the cytochrome P450 enzymes genes (CYP2D6) influence metabolism of codeine, tramadol, hydrocodone, oxycodone, and tricyclic antidepressants. Blood concentrations of some NSAIDs depend on CYP2C9 and/or CYP2C8 activity. Additional candidate genes encode for opioid receptors, transporters, and other molecules important for pharmacotherapy in pain management. However, PGx studies are often contradictory, slowing the uptake of this information. This is likely due, in large part, to a lack of robust evidence demonstrating clinical utility and to its polygenic response modulated by other exogenous or epigenetics factors. Novel therapies, including targeting of epigenetic changes and gene therapy-based approaches, broaden future options to improve understanding of pain and the treatment of people who suffer it.

Chronic Pain Features Relate to Quality of Life More than Physiopathology: A Cross-Sectional Evaluation in Pain Clinics

OBJECTIVE

To compare the impact of chronic pain physiopathology on health-related quality of life (HR-QoL), considering the influence of pain features and psychosocial adjustment (intensity, interference, psychological comorbidities, and sleep quality).

DESIGN

A cross-sectional study involving 1,025 noncancer patients with predominantly neuropathic, nociceptive, or mixed chronic pain conditions was conducted in 88 pain clinics within Spain. The EuroQol-5 Dimensions instrument (EQ-5D) was used to measure HR-QoL. The Brief Pain Inventory (BPI), Hospital Anxiety and Depression Scale (HADS), and sleep scale developed for the MOS study (MOS-SQ) were used to measure pain features and psychosocial adjustment. Multivariate analyses were used to model HR-QoL measures.

RESULTS

All patients reported very low HR-QoL. The mean EQ-5D index scores were 0.33, 0.36, and 0.37 in the mixed, neuropathic, and nociceptive pain groups, respectively. The differences did not reach statistical significance (P = 0.057). Patients with nociceptive pain had less pain (least pain intensity score: 4.7 vs. 5.2 in the other groups; P = 0.006), less interference with daily activities (BPI average interference score: 6.3 vs. 6.6 and 6.7 in the neuropathic and mixed pain groups, respectively; P = 0.013), less anxiety (HADS score: 8.5 vs. 9.6 and 9.7 in the same respective groups; P = 0.001), and fewer sleep problems (MOS-SQ sleep problems index: 46.8 vs. 52.2 and 50.2 in the same respective groups; P = 0.005). In the adjusted analyses, HR-QoL measures were explained by pain intensity, anxiety, and sleep quality, but not by physiopathological pain type.

CONCLUSIONS

Pain features, particularly intensity, have a greater impact than pain physiopathology on HR-QoL. Distinct physiopathological mechanisms give rise to different pain features that, in turn, may mediate the HR-QoL of patients with chronic pain. This could be used to improve pain management strategies.

Patient Satisfaction with Spanish Pain Centers: Observational Study with More than 3,000 Patients

Chronic pain is a serious problem in Spain. This multicenter, epidemiological 3-month follow-up study investigates pain management efficacy in Spanish centers using patient satisfaction criteria. 3,414 eligible adult patients (65,6% female) with moderate to severe chronic pain from 146 pain centers were included. Patient satisfaction was assessed based onto question 18 of Spanish healthcare barometer-CSI. Pain evolution (Brief Pain Inventory-Short Form (BPI-SF) and visual analog scale (VAS)), quality of life/EuroQol-5, and pain control expectations fulfillment were also assessed. Mean age was 61.3 years. 64.4% of participating centers employed multidisciplinary pain management approach. After 3 months, mean patient satisfaction was 7.8 (1-10) on the CIS barometer. Medical staff received the highest scores, whereas waiting for tests, appointment request to appointment date time, and waiting times at the center the lowest. Mean pain decreased from 7.4 to 4.0; BPI-SF intensity decreased from 6.5 to 3.8; pain control expectations were met in 78.7% of patients; EuroQoL-5D utility index increased from 0.37 to 0.62, p < 0.001, and health status (VAS) from 40.6 to 61.9, p < 0.001. Chronic pain patients (90%) are satisfied with Spanish centers care; 80% had their pain control expectations met. Quality of life improved remarkably: 71% felt moderately to significantly better. However, waiting times need improvement.

Adaptation and validation of the Spanish version of the graded chronic pain scale

OBJECTIVE

To adapt the Graded Chronic Pain Scale for use in Primary care patients in Spain, and to assess its psychometric properties.

METHODS

Clinical measures observational study investigating the severity of chronic pain. The methodology included a process of translation and back-translation following the international guidelines. Study participants were 75 patients who experienced lower back pain for more than six months and were sent to Primary Care physiotherapy units. Internal consistency, construct validity, test-retest reliability, floor and ceiling effects, and answering capacity were analysed.

RESULTS

The Spanish version of the Graded Chronic Pain Scale had a high internal consistency, with a Cronbach's alpha of 0.87 and intraclass correlation coefficient of 0.81. Regarding construct validity, it was identified that two factors explained 72.37% of the variance. Convergent validity showed a moderate positive correlation with the Visual Analogue Scale, the activity avoidance subscale of the Tampa Scale of Kinesophobia, the Pain Catastrophizing Scale, the Roland-Morris Low Back Pain and Disability Questionnaire, and the FearAvoidance Beliefs Questionnaire. A moderate negative correlation was identified with the Chronic Pain Self-Efficacy Scale. The mean time of questionnaire administration was 2minutes and 28seconds.

CONCLUSIONS

The Spanish version of the Graded Chronic Pain Scale appears to be a valid, reliable, and useful tool for measuring chronic pain at an early stage in Primary Care settings in Spain.