Accuracy of neuropathic pain measurements in patients with symptoms of polyneuropathy: validation of painDETECT, Self-Completed Leeds Assessment of Neuropathic Symptoms and Signs, and Douleur Neuropathique 4

Pain is a common symptom in patients referred to polyneuropathy assessment. Diagnostic evaluation and choice of treatment may depend on whether the pain is likely to be neuropathic or not. This study aimed to investigate the diagnostic accuracy of 3 tools commonly used to differentiate between neuropathic and nonneuropathic pain. To accomplish this, we included patients with bilateral distal lower extremity pain, referred to neurological outpatient clinics at 5 Norwegian University hospitals for polyneuropathy assessment. The patients filled in Norwegian versions of painDETECT, the Self-Completed Leeds Assessment of Neuropathic Symptoms and Signs (S-LANSS), and the clinician-rated Douleur Neuropathique 4 (DN4). All patients underwent a clinical examination and nerve conduction measurements and were classified according to the NeuPSIG neuropathic pain criteria (reference standard). In total, 729 patients were included, of which 63% had neuropathic pain by the reference standard. Only DN4 demonstrated high sensitivity (0.87), whereas all 3 tools had low specificity (≤0.65). Importantly, the tools' predictive ability was unsatisfactory; The probability of getting a correct test result was 3 quarters at best, and at worst, no better than two fifths. Consequently, we show that neither DN4, painDETECT, nor S-LANSS can be confidently used to assess neuropathic pain in a neurological outpatient population with symptoms of polyneuropathy

Cost–utility analysis of antibiotic treatment in patients with chronic low back pain and Modic changes: results from a randomised, placebo-controlled trial in Norway (the AIM study)

Objective To evaluate the cost–utility of 100 days of antibiotics in patients with chronic low back pain (LBP) and type I or II Modic changes included in the Antibiotic treatment In patients with chronic low back pain and Modic changes (AIM) study. Design A cost–utility analysis from a societal and healthcare perspective alongside a double-blinded, parallel group, placebo, multicentre trial. Setting Hospital outpatient clinics at six hospitals in Norway. The main results from the AIM study showed a small effect in back-related disability in favour of the antibiotics group, and slightly larger in those with type I Modic changes, but this effect was below the pre-defined threshold for clinically relevant effect. Participants 180 patients with chronic LBP, previous disc herniation and Modic changes type I (n=118) or type II (n=62) were randomised to antibiotic treatment (n=89) or placebo-control (n=91). Interventions Oral treatment with either 750 mg amoxicillin or placebo three times daily for 100 days. Main outcome measures Quality-adjusted life years (QALYs) by EuroQoL-5D over 12 months and costs for healthcare and productivity loss measured in Euro (€1=NOK 10), in the intention-to-treat population. Cost–utility was expressed in incremental cost-effectiveness ratio (ICER). Results Mean (SD) total cost was €21 046 (20 105) in the amoxicillin group and €19 076 (19 356) in the placebo group, mean difference €1970 (95% CI; −3835 to 7774). Cost per QALY gained was €24 625. In those with type I Modic changes, the amoxicillin group had higher healthcare consumption than the placebo group, resulting in €39 425 per QALY gained. Given these ICERs and a willingness-to-pay threshold of €27 500 (NOK 275 000), the probability of amoxicillin being cost-effective was 51%. Even when the willingness-to-pay threshold increased to €55 000, the probability of amoxicillin being cost-effective was never higher than 53%. Conclusions Amoxicillin treatment showed no evidence of being cost-effective for people with chronic LBP and Modic changes during 1-year follow-up.publishedVersio

Characteristics of older adults with back pain associated with choice of first primary care provider: a cross-sectional analysis from the BACE-N cohort study

Objectives: To describe characteristics of older adults with back pain in primary care, and to assess associations between patient characteristics and type of first primary care provider (general practitioner (GP), physiotherapist (PT) or chiropractor). Design: Cross-sectional analysis from the Back Complaints in the Elders-Norway cohort study. Setting: Norwegian GP, PT and chiropractic primary care centres. Participants: Patients aged ≥55 years seeking Norwegian primary care with a new episode of back pain were invited to participate. Between April 2015 and February 2020, we included 452 patients: 127 first visited a GP, 130 first visited a PT and 195 first visited a chiropractor. Primary and secondary outcome measures: For the first objective, the outcome measure was descriptive statistics of patient characteristics, covering the following domains: sociodemographic, general health, current and previous back pain, psychological and clinical factors. For the second objective, first primary care provider was the outcome measure. Associations between patient characteristics and visiting a GP or PT compared with a chiropractor were assessed with multiple multinomial regression analyses. Results: Median (IQR) age was 66 (59–72) years. Levels of back-related disability was moderate to severe, with a median (IQR) Roland-Morris Disability Questionnaire (range 0–24) score of 9 (5–13). Recurring episodes were common, 301 (67%) patients had monthly or yearly recurrences. Patients with worse back-related disability, longer duration of symptoms, lower expectations for full recovery and worse physical performance measured with the Back Performance Scale had higher odds of visiting a GP or PT compared with a chiropractor (p<0.05). Conclusion: Older back pain patients in primary care had moderate to severe levels of back-related disability, and most had recurring episodes. Our results suggest that older adult’s choice of first primary care provider was associated with important patient characteristics, which highlights the need for caution with generalisations of study results across primary care populations

Characteristics of older adults with back pain associated with choice of first primary care provider: a cross-sectional analysis from the BACE-N cohort study

Objectives To describe characteristics of older adults with back pain in primary care, and to assess associations between patient characteristics and type of first primary care provider (general practitioner (GP), physiotherapist (PT) or chiropractor). Design Cross-sectional analysis from the Back Complaints in the Elders-Norway cohort study. Setting Norwegian GP, PT and chiropractic primary care centres. Participants Patients aged ≥55 years seeking Norwegian primary care with a new episode of back pain were invited to participate. Between April 2015 and February 2020, we included 452 patients: 127 first visited a GP, 130 first visited a PT and 195 first visited a chiropractor. Primary and secondary outcome measures For the first objective, the outcome measure was descriptive statistics of patient characteristics, covering the following domains: sociodemographic, general health, current and previous back pain, psychological and clinical factors. For the second objective, first primary care provider was the outcome measure. Associations between patient characteristics and visiting a GP or PT compared with a chiropractor were assessed with multiple multinomial regression analyses. Results Median (IQR) age was 66 (59–72) years. Levels of back-related disability was moderate to severe, with a median (IQR) Roland-Morris Disability Questionnaire (range 0–24) score of 9 (5–13). Recurring episodes were common, 301 (67%) patients had monthly or yearly recurrences. Patients with worse back-related disability, longer duration of symptoms, lower expectations for full recovery and worse physical performance measured with the Back Performance Scale had higher odds of visiting a GP or PT compared with a chiropractor (p<0.05). Conclusion Older back pain patients in primary care had moderate to severe levels of back-related disability, and most had recurring episodes. Our results suggest that older adult’s choice of first primary care provider was associated with important patient characteristics, which highlights the need for caution with generalisations of study results across primary care populations

Clinical Utility of the 6-Item CTS, Boston-CTS, and Hand-Diagram for Carpal Tunnel Syndrome

Background: Self-reported measures are often used in research and clinical practice to diagnose carpal tunnel syndrome (CTS) and guide therapeutic choices. We aimed to assess the clinical utility of the Norwegian versions of two self-reported outcome measures for symptom severity assessment, the 6-item CTS (CTS-6), and Boston-CTS (BCTQ), and of one diagnostic measure, the hand-diagram, by evaluating measurement properties including discriminative ability for severity assessment (CTS-6, BCTQ), and diagnosis of CTS (hand-diagram). Methods: We performed forward and backward translation and cultural adaptation of the Norwegian CTS-6 and BCTQ. Following COSMIN guidelines, we investigated internal consistency, reliability, construct validity, and discriminative ability for distinguishing between severity levels of CTS in patients with confirmed CTS for the CTS-6 and BCTQ and reliability and discriminative ability for diagnosing CTS for the hand-diagram. Results: Two hundred and fifty-one patients referred for diagnostic work-up for CTS with nerve conduction studies (NCS) participated. The CTS-6 and BCTQ had acceptable internal consistency (Crohnbach's α = 0.82 and 0.86, respectively), reliability (ICC = 0.86 and 0.90; SEM = 0.24 and 0.20; SDC95% = 0.68 and 0.55, respectively), construct validity (all eight pre-defined hypotheses confirmed) and discriminative ability to distinguish between severity levels of CTS [Area under the curve (AUC) = 0.75, 95% CI 0.64–0.85]. The hand-diagram had acceptable reliability (Cohen's kappa = 0.69) and discriminative ability to diagnose CTS (sensitivity = 0.72, specificity = 0.90). Conclusion: Our findings support the clinical utility of the CTS-6 and BCTQ for symptom severity assessment and of the hand-diagram for diagnostic screening

Clinical Utility of the 6-Item CTS, Boston-CTS, and Hand-Diagram for Carpal Tunnel Syndrome

Background: Self-reported measures are often used in research and clinical practice to diagnose carpal tunnel syndrome (CTS) and guide therapeutic choices. We aimed to assess the clinical utility of the Norwegian versions of two self-reported outcome measures for symptom severity assessment, the 6-item CTS (CTS-6), and Boston-CTS (BCTQ), and of one diagnostic measure, the hand-diagram, by evaluating measurement properties including discriminative ability for severity assessment (CTS-6, BCTQ), and diagnosis of CTS (hand-diagram). Methods: We performed forward and backward translation and cultural adaptation of the Norwegian CTS-6 and BCTQ. Following COSMIN guidelines, we investigated internal consistency, reliability, construct validity, and discriminative ability for distinguishing between severity levels of CTS in patients with confirmed CTS for the CTS-6 and BCTQ and reliability and discriminative ability for diagnosing CTS for the hand-diagram. Results: Two hundred and fifty-one patients referred for diagnostic work-up for CTS with nerve conduction studies (NCS) participated. The CTS-6 and BCTQ had acceptable internal consistency (Crohnbach’s α = 0.82 and 0.86, respectively), reliability (ICC = 0.86 and 0.90; SEM = 0.24 and 0.20; SDC95% = 0.68 and 0.55, respectively), construct validity (all eight pre-defined hypotheses confirmed) and discriminative ability to distinguish between severity levels of CTS [Area under the curve (AUC) = 0.75, 95% CI 0.64–0.85]. The hand-diagram had acceptable reliability (Cohen’s kappa = 0.69) and discriminative ability to diagnose CTS (sensitivity = 0.72, specificity = 0.90). Conclusion: Our findings support the clinical utility of the CTS-6 and BCTQ for symptom severity assessment and of the hand-diagram for diagnostic screening

Identifying latent subgroups in the older population seeking primary health care for a new episode of back pain - findings from the BACE-N cohort

BACKGROUND: Back pain is the number one condition contributing to years lived with disability worldwide, and one of the most common reasons for seeking primary care. Research on this condition in the ageing population is sparse. Further, the heterogeneity of patients with back pain complicates the management in clinical care. It is possible that subgrouping people with similar characteristics would improve management. This paper aimed to identify latent classes based on demographics, pain characteristics, psychosocial behavior, and beliefs and attitudes about back pain, among older patients seeking primary care with a new episode of back pain, and to examine if there were differences regarding the classes' first point-of-contact.METHODS: The study was part of the international BACE (Back complaints in elders) consortium and included 435 patients aged ≥ 55 years seeking primary care (general practitioners, physiotherapists, and chiropractors) in Norway from April 2015 to March 2020. A latent class analysis was performed to identify latent classes. The classes were described in terms of baseline characteristics and first point-of-contact in primary care.RESULTS: Four latent classes were identified. The mean age was similar across groups, as were high expectations towards improvement. Class 1 (n = 169, 39%), the "positive" class, had more positive attitudes and beliefs, less pain catastrophizing and shorter duration of current pain episode. Class 2 (n = 31, 7%), the "fearful" class, exhibited the most fear avoidance behavior, and had higher mean pain intensity. Class 3 (n = 33, 8%), the "distressed" class, had the highest scores on depression, disability, and catastrophizing. Finally, class 4 (n = 202, 46%), the "hopeful" class, showed the highest expectations for recovery, although having high pain intensity. The identified four classes showed high internal homogeneity, sufficient between-group heterogeneity and were considered clinically meaningful. The distribution of first point-of-contact was similar across classes, except for the positive class where significantly more patients visited chiropractors compared to general practitioners and physiotherapists.CONCLUSIONS: The identified classes may contribute to targeting clinical management of these patients. Longitudinal research on these latent classes is needed to explore whether the latent classes have prognostic value. Validation studies are needed to evaluate external validity.TRIAL REGISTRATION: Clinicaltrials.gov NCT04261309.</p

External validation and updating of prognostic prediction models for nonrecovery among older adults seeking primary care for back pain

Prognostic prediction models for 3 different definitions of nonrecovery were developed in the Back Complaints in the Elders study in the Netherlands. The models' performance was good (optimism-adjusted area under receiver operating characteristics [AUC] curve ≥0.77, R2 ≥0.3). This study aimed to assess the external validity of the 3 prognostic prediction models in the Norwegian Back Complaints in the Elders study. We conducted a prospective cohort study, including 452 patients aged ≥55 years, seeking primary care for a new episode of back pain. Nonrecovery was defined for 2 outcomes, combining 6- and 12-month follow-up data: Persistent back pain (≥3/10 on numeric rating scale) and persistent disability (≥4/24 on Roland-Morris Disability Questionnaire). We could not assess the third model (self-reported nonrecovery) because of substantial missing data (&gt;50%). The models consisted of biopsychosocial prognostic factors. First, we assessed Nagelkerke R2 , discrimination (AUC) and calibration (calibration-in-the-large [CITL], slope, and calibration plot). Step 2 was to recalibrate the models based on CITL and slope. Step 3 was to reestimate the model coefficients and assess if this improved performance. The back pain model demonstrated acceptable discrimination (AUC 0.74, 95% confidence interval: 0.69-0.79), and R2 was 0.23. The disability model demonstrated excellent discrimination (AUC 0.81, 95% confidence interval: 0.76-0.85), and R2 was 0.35. Both models had poor calibration (CITL &lt;0, slope &lt;1). Recalibration yielded acceptable calibration for both models, according to the calibration plots. Step 3 did not improve performance substantially. The recalibrated models may need further external validation, and the models' clinical impact should be assessed.</p

Modifiable prognostic factors of high costs related to healthcare utilization among older people seeking primary care due to back pain: an identification and replication study

BACKGROUND: Back pain is an extensive burden to our healthcare system, yet few studies have explored modifiable prognostic factors associated with high costs related to healthcare utilization, especially among older back pain patients. The aims of this study were to identify modifiable prognostic factors for high costs related to healthcare utilization among older people seeking primary care with a new episode of back pain; and to replicate the identified associations in a similar cohort, in a different country. METHODS: Data from two cohort studies within the BACE consortium were used, including 452 and 675 people aged ≥55 years seeking primary care with a new episode of back pain. High costs were defined as costs in the top 25th percentile. Healthcare utilization was self-reported, aggregated for one-year of follow-up and included: primary care consultations, medications, examinations, hospitalization, rehabilitation stay and operations. Costs were estimated based on unit costs collected from national pricelists. Nine potential modifiable prognostic factors were selected based on previous literature. Univariable and multivariable binary logistic regression models were used to identify and replicate associations (crude and adjusted for selected covariates) between each modifiable prognostic factor and high costs related to healthcare utilization. RESULTS: Four modifiable prognostic factors associated with high costs related to healthcare utilization were identified and replicated: a higher degree of pain severity, disability, depression, and a lower degree of physical health-related quality of life. Kinesiophobia and recovery expectations showed no prognostic value. There were inconsistent results across the two cohorts with regards to comorbidity, radiating pain below the knee and mental health-related quality of life. CONCLUSION: The factors identified in this study may be future targets for intervention with the potential to reduce high costs related to healthcare utilization among older back pain patients. TRIAL REGISTRATION: ClinicalTrials.gov NCT04261309, 07 February 2020. Retrospectively registered