Healthcare utilization and related costs among older people seeking primary care due to back pain: findings from the BACE-N cohort study

OBJECTIVES

To describe healthcare utilization and estimate associated costs during 1 year of follow-up among older people seeking primary care due to a new episode back pain and to describe healthcare utilization across patients with different risk profiles stratified using the StarT Back Screening Tool (SBST).

DESIGN

Prospective cohort study.

PARTICIPANTS AND SETTING

A total of 452 people aged ≥55 years seeking Norwegian primary care with a new episode of back pain were included.

OUTCOME MEASURES

The primary outcome of this study was total cost of healthcare utilization aggregated for 1 year of follow-up. Secondary outcomes included components of healthcare utilization aggregated for 1 year of follow-up. Healthcare utilization was self-reported and included: primary care consultations, medications, examinations, hospitalisation, rehabilitation stay, and operations. Costs were estimated based on unit costs collected from national pricelists. Healthcare utilization across patients with different SBST risk profiles was compared using Kruskal-Wallis test, post hoc Mann-Whitney U tests and Bonferroni adjustment.

RESULTS

In total, 438 patients were included in the analysis. Mean (BCa 95% CI) total cost per patient over 1 year was €825 (682-976). Median (BCa 95% CI) total cost was €364 (307-440). The largest cost category was primary care consultations, accounting for 56% of total costs. Imaging rate was 34%. The most commonly used medication was paracetamol (27%-35% of patients). Medium- and high-risk patients had a significantly higher degree of healthcare utilization compared with low-risk patients (p<0.030).

CONCLUSION

This study estimated a 1 year mean and median cost of healthcare utilization of €825 and €364, respectively. Patients within the top 25th percentile accounted for 77% of all costs. Patients classified as medium risk and high risk had a significantly higher degree of healthcare utilization compared with patients classified as low risk.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov NCT04261309, results.

The predictive value of quantitative sensory testing: a systematic review on chronic postoperative pain and the analgesic effect of pharmacological therapies in patients with chronic pain

Studies have suggested that quantitative sensory testing (QST) might hold a predictive value for the development of chronic postoperative pain and the response to pharmacological interventions. This review systematically summarizes the current evidence on the predictive value of QST for chronic postoperative pain and the effect of pharmacological interventions. The main outcome measures were posttreatment pain intensity, pain relief, presence of moderate-to-severe postoperative pain, responders of 30% and 50% pain relief, or validated questionnaires on pain and disability. A systematic search of MEDLINE and EMBASE yielded 25 studies on surgical interventions and 11 on pharmacological interventions. Seventeen surgical and 11 pharmacological studies reported an association between preoperative or pretreatment QST and chronic postoperative pain or analgesic effect. The most commonly assessed QST modalities were pressure stimuli (17 studies), temporal summation of pain (TSP, 14 studies), and conditioned pain modulation (CPM, 16 studies). Of those, the dynamic QST parameters TSP (50%) and CPM (44%) were most frequently associated with chronic postoperative pain and analgesic effects. A large heterogeneity in methods for assessing TSP (n = 4) and CPM (n = 7) was found. Overall, most studies demonstrated low-to-moderate levels of risk of bias in study design, attrition, prognostic factors, outcome, and statistical analyses. This systematic review demonstrates that TSP and CPM show the most consistent predictive values for chronic postoperative pain and analgesic effect, but the heterogeneous methodologies reduce the generalizability and hence call for methodological guidelines.

The association between selected genetic variants and individual differences in experimental pain

OBJECTIVES

The underlying mechanisms for individual differences in experimental pain are not fully understood, but genetic susceptibility is hypothesized to explain some of these differences. In the present study we focus on three genetic variants important for modulating experimental pain related to serotonin (SLC6A4 5-HTTLPR/rs25531 A>G), catecholamine (COMT rs4680 Val158Met) and opioid (OPRM1 rs1799971 A118G) signaling. We aimed to investigate associations between each of the selected genetic variants and individual differences in experimental pain.

METHODS

In total 356 subjects (232 low back pain patients and 124 healthy volunteers) were genotyped and assessed with tests of heat pain threshold, pressure pain thresholds, heat pain tolerance, conditioned pain modulation (CPM), offset analgesia, temporal summation and secondary hyperalgesia. Low back pain patients and healthy volunteers did not differ in regards to experimental test results or allelic frequencies, and were therefore analyzed as one group. The associations were tested using analysis of variance and the Kruskal-Wallis test.

RESULTS

No significant associations were observed between the genetic variants (SLC6A4 5-HTTLPR/rs25531 A>G, COMT rs4680 Val158Met and OPRM1 rs1799971 A118G) and individual differences in experimental pain (heat pain threshold, pressure pain threshold, heat pain tolerance, CPM, offset analgesia, temporal summation and secondary hyperalgesia).

CONCLUSIONS

The selected pain-associated genetic variants were not associated with individual differences in experimental pain. Genetic variants well known for playing central roles in pain perception failed to explain individual differences in experimental pain in 356 subjects. The finding is an important contribution to the literature, which often consists of studies with lower sample size and one or few experimental pain assessments.

Quantitative Sensory Testing to Predict Postoperative Pain

Purpose of Review

We review the relevance of quantitative sensory testing (QST) in light of acute and chronic postoperative pain and associated challenges.

Recent Findings

Predicting the occurrence of acute and chronic postoperative pain with QST can help identify patients at risk and allows proactive preventive management. Generally, central QST testing, such as temporal summation of pain (TSP) and conditioned pain modulation (CPM), appear to be the most promising modalities for reliable prediction of postoperative pain by QST. Overall, QST testing has the best predictive value in patients undergoing orthopedic procedures.

Summary

Current evidence underlines the potential of preoperative QST to predict postoperative pain in patients undergoing elective surgery. Implementing QST in routine preoperative screening can help advancing traditional pain therapy toward personalized perioperative pain medicine.

Quantitative Sensory Testing Discriminates Central Sensitization Inventory Scores in Participants with Chronic Musculoskeletal Pain: An Exploratory Study

BACKGROUND

The Central Sensitization Inventory (CSI) is often used in clinical settings to screen for the presence of central sensitization. However, various cutoff scores have been reported for this tool, and scores have not been consistently associated with widespread pain sensitivity as measured with quantitative sensory testing (QST). The purpose of this study was to compare QST profiles among asymptomatic controls and participants with chronic musculoskeletal pain (CMP), and to determine the association between self-report questionnaires and QST in participants with CMP.

METHODS

Twenty asymptomatic controls and 46 participants with CMP completed the CSI, PROMIS-29, and QST assessments of mechanical and thermal pain thresholds remote to the area of pain. Receiver Operating Characteristic analysis revealed a cutoff score of 33.5 for the CSI. PROMIS-29 Quality of Life (QOL) inventory and QST measures were compared between low and high CSI groups.

RESULTS

The high CSI group (n = 19) had significantly lower mechanical and thermal pain thresholds, and larger impairments in QOL measures, compared to the low CSI group (n = 27) and asymptomatic controls. Participants with CSI scores < 33.5 presented similarly to asymptomatic controls. Anxiety, pain interference, and CSI scores demonstrated the highest number of significant associations to QST measures.

CONCLUSION

A cutoff score of 33.5 on the CSI may be useful for discriminating widespread pain sensitivity and quality of life impairments in participants with CMP. Future studies should consider how the presence of high or low CSI may impact differential diagnosis, prognosis, and treatment responsiveness for patients with primary or secondary CMP.