Patterns of drug treatment in patients with osteoarthritis and chronic low back pain in Japan: a retrospective database study

Use of analgesics before and after total joint replacement in working-age Japanese patients with knee and hip osteoarthritis: A retrospective database study

Background

Patterns of analgesic use before and after total joint replacement (TJR) in patients with knee/hip osteoarthritis (OA) is not well reported.

Methods

This retrospective longitudinal analysis used JMDC claims data of patients who underwent knee/hip replacement surgery from 2010 to 2019. Primary outcome was proportion of patients using analgesics pre-surgery, immediately post-surgery, and in post-surgery period. Factors affecting post-surgery analgesic withdrawal and opioid prescriptions were assessed using logistic regression.

Results

Of all (N = 3168) patients, those with knee OA (91.1 %) and hip OA (82.5 %) used analgesics pre-surgery, and 96.1 % with knee OA and 84.9 % with hip OA required analgesics even 3 months post-surgery. NSAIDs were most commonly used pre- and post-surgery in both OA groups. Before surgery, 15.6 % (knee OA) and 13.7 % of patients (hip OA) used weak opioids, and 23.1 % (knee OA) and 10.5 % (hip OA) of patients continued them post-surgery. Strong opioid use was noted in 2.2 % and 1.2 % of patients pre-surgery, and 5.8 % and 3.4 % of patients post-surgery in the knee and hip OA groups, respectively. Using pre-operative oral NSAIDs (odds ratio [OR]:0.56; 95 % confidence interval [CI]:0.44-0.72) and weak opioids (OR:0.58; 95 % CI:0.38-0.87) associated with withdrawal of post-surgery analgesics in patients with hip OA, and using intra-articular hyaluronic acid pre-surgery (OR:0.45; 95 % CI:0.21-0.97) was significant in patients with knee OA. Using weak (OR:4.59; 95 % CI:3.44-6.13) and strong opioids (OR:2.48; 95 % CI:1.01-6.07) pre-surgery associated with post-operative opioid use in patients with hip OA, and weak opioid use was significant in patients with knee OA (OR:7.00; 95 % CI:4.65-10.54).

Conclusion

This study reported difference in analgesic use before and after TJR, and that many patients required analgesics even 3 months after TJR surgery in Japan. Pre-operative analgesic use associated with continued use after surgery. Optimal pain management before and immediately after TJR is important to reduce post-operative analgesic use, especially opioids.

Prevalence of Nonsteroidal Antiinflammatory Drugs Prescribed for Osteoarthritis: A Systematic Review and Meta-Analysis of Observational Studies

OBJECTIVE

Our systematic review aimed to investigate the proportion of participants with osteoarthritis who were prescribed nonsteroidal antiinflammatory drugs (NSAIDs) by their health care provider.

METHODS

Electronic databases were searched for observational studies reporting NSAID prescribing to participants with diagnosed osteoarthritis of any region. Risk of bias was assessed using a tool designed for observational studies measuring prevalence. Random and fixed-effects meta-analysis was used. Meta-regression investigated study-level factors associated with prescribing. The overall evidence quality was assessed using Grading of Recommendations Assessment, Development, and Evaluation criteria.

RESULTS

Fifty-one studies were included, published between 1989 and 2022, with 6,494,509 participants. The mean age of participants was 64.7 years (95% confidence interval [95% CI] 62.4, 67.0; n = 34 studies). Most studies were from Europe and Central Asia (n = 23 studies), and North America (n = 12 studies). Most studies were judged to be at low risk of bias (75%). Heterogeneity was eliminated when removing studies with a high risk of bias, to give a pooled estimate of NSAIDs prescribing to participants with osteoarthritis of 43.8% (95% CI 36.8, 51.1; moderate quality of evidence). Meta-regression determined that prescribing was associated with year (decreased prescribing over time; P = 0.05) and geographic region (P = 0.03; higher in Europe and Central Asia and in South Asia than in North America) but not with clinical setting.

CONCLUSION

Data from over 6.4 million participants with osteoarthritis between 1989 and 2022 indicate that NSAID prescribing has decreased over time and that prescribing differs between geographic locations.

Sensitivity and specificity of algorithms for the identification of nonspecific low back pain in medico-administrative databases

ABSTRACT

Identifying nonspecific low back pain (LBP) in medico-administrative databases is a major challenge because of the number and heterogeneity of existing diagnostic codes and the absence of standard definitions to use as reference. The objective of this study was to evaluate the sensitivity and specificity of algorithms for the identification of nonspecific LBP from medico-administrative data using self-report information as the reference standard. Self-report data came from the PROspective Québec Study on Work and Health , a 24-year prospective cohort study of white-collar workers. All diagnostic codes that could be associated with nonspecific LBP were identified from the International Classification of Diseases, Ninth and Tenth Revisions ( ICD-9 and ICD-10 ) in physician and hospital claims. Seven algorithms for identifying nonspecific LBP were built and compared with self-report information. Sensitivity analyses were also conducted using more stringent definitions of LBP. There were 5980 study participants with (n = 2847) and without (n = 3133) LBP included in the analyses. An algorithm that included at least 1 diagnostic code for nonspecific LBP was best to identify cases of LBP in medico-administrative data with sensitivity varying between 8.9% (95% confidence interval [CI] 7.9-10.0) for a 1-year window and 21.5% (95% CI 20.0-23.0) for a 3-year window. Specificity varied from 97.1% (95% CI 96.5-97.7) for a 1-year window to 90.4% (95% CI 89.4-91.5) for a 3-year window. The low sensitivity we found reveals that the identification of nonspecific cases of LBP in administrative data is limited, possibly due to the lack of traditional medical consultation.

Comparative effectiveness of early initiation of oral nonsteroidal anti-inflammatory drug and oral acetaminophen therapies on the time to knee replacement in patients with knee osteoarthritis in Japan

BACKGROUND

Although disease-modifying properties of nonsteroidal anti-inflammatory drugs (NSAIDs) for osteoarthritis (OA) have been reported, the effects of NSAIDs on OA progression remain controversial. The purpose of this study was to investigate the effect of early initiation of oral NSAID therapy on the progression of knee OA.

METHODS

In this retrospective cohort study, we extracted data of patients newly diagnosed with knee OA between November 2007 and October 2018 from a Japanese claims database. The primary outcome was the time to knee replacement (KR), and the secondary outcome was the time to composite event including joint lavage and debridement, osteotomy, or arthrodesis in addition to KR. Weighted Cox regression analysis with standardized mortality/morbidity ratio (SMR) weight was performed to compare the outcomes between patients prescribed oral NSAID (NSAID group) and those prescribed oral acetaminophen (APAP) (APAP group) early after a diagnosis of knee OA. Propensity scores were calculated using logistic regression conditioned on potential confounding factors, and SMR weights were calculated using the propensity scores.

RESULTS

The study population comprised 14,261 patients, who were divided into two groups as follows: 13,994 in the NSAID group and 267 in the APAP group. The mean ages of patients in the NSAID and APAP groups were 56.9 and 56.1 years, respectively. Furthermore, 62.01% and 68.16% patients in the NSAID and APAP groups, respectively, were female. The NSAID group had a reduced risk of KR compared with the APAP group in the analysis using SMR weighting (SMR-weighted hazard ratio, 0.19; 95% confidence interval, 0.05-0.78). While no statistically significant difference was found for the risk of composite event between the two groups (SMR-weighted hazard ratio, 0.56; 95% confidence interval, 0.16-1.91).

CONCLUSIONS

The risk of KR in the NSAID group was significantly lower than that in the APAP group after accounting for residual confounding using SMR weighting. This finding suggests that oral NSAID therapy early after the initial diagnosis is associated with a reduced risk of KR in patients with symptomatic knee OA.

Opioid Utility and Hospital Outcomes Among Inpatients Admitted With Osteoarthritis and Spine Disorders

OBJECTIVE

The aim of the study is to evaluate opioid analgesic utilization and predictors for adverse events during hospitalization and discharge disposition among patients admitted with osteoarthritis or spine disorders.

DESIGN

This is a retrospective study of 12,747 adult patients admitted to six private community hospitals from 2017 to 2020. Opioid use during hospitalization and risk factors for hospital-acquired adverse events and nonhome discharge were investigated.

RESULTS

The total number of patients using opioids decreased; however, the daily morphine milligram equivalent use for patients on opioids increased from 2017 to 2020. Increased odds of nonhome discharge were associated with older age, Medicaid, Medicare insurance, and increased lengths of stay, increased body mass index, daily morphine milligram equivalent, and electrolyte replacement in the osteoarthritis group. In the spine group, older age, Black race, Medicaid, Medicare, no insurance, increased Charlson Comorbidity Index, lengths of stay, polypharmacy, and heparin use were associated with nonhome discharge. Adverse events were associated with increased age, lengths of stay, Medicare, polypharmacy, antiemetic, and benzodiazepine use in the osteoarthritis group and increased Charlson Comorbidity Index, lengths of stay, and electrolyte replacement in the spine group.

CONCLUSIONS

Despite the decreasing number of patients using opioids over the years, patients on opioids had an increased daily morphine milligram equivalent over the same period.

Chronic pain and continuity of analgesic treatment during the COVID-19 pandemic

INTRODUCTION

Chronic pain can trigger both physical and mental health complications. During the COVID-19 pandemic, patients with chronic diseases have had reduced access to some medications.

OBJECTIVE

To determine the pharmacological management of patients with chronic pain and its continuity during the COVID-19 pandemic.

METHODS

This was a retrospective longitudinal study of the continuity of analgesic use in patients with chronic pain between September 1, 2019 and February 28, 2021 based on a drug dispensing database. Survival analysis was performed until the discontinuation of chronic analgesics.

RESULTS

A total of 12,701 patients who were being treated for chronic pain were identified. Their median age was 70.3 years, and 74.4% were women. The pain of rheumatological origin was the most frequent etiology (46.1%); the most used medications were nonopioid analgesics (78.9%), pain modulators (24.8%) and opioid analgesics (23.3%). A total of 76.1% of the patients experienced interruptions in their management during the study period. The median time to the first interruption of treatment was 5.0 months (95% CI: 4.8-5.2). Those who were treated for oncological pain experienced a greater number of interruptions in their management.

CONCLUSIONS

The pharmacological management of patients with chronic pain is heterogeneous, and this real-world study showed that a high proportion of patients experienced an interruption of pain management during the 12 months following the onset of the COVID-19 pandemic.

Pain Intensity and Trajectory Following Intra-Articular Injection of Mono-Iodoacetate in Experimental Osteoarthritis: A Meta-Analysis of In Vivo Studies

OBJECTIVE

Although most frequently used in experimental osteoarthritis (OA) pain induction, intra-articular mono-iodoacetate (MIA) injection lacks concluded references for dose selection and timing of intervention. Herein, we aimed to compare the pain intensity of rats induced by different doses of MIA and explored the trajectory of pain.

DESIGN

PubMed, Embase, and Web of Science were searched up to June 2021 for literatures involving MIA experiments investigating OA pain. Pain intensity was measured based on weightbearing distribution (WBD) and paw withdrawal thresholds (PWT), and the pain trajectory was constructed by evaluating pain intensity at a series of time points after MIA injection. A conventional meta-analysis was conducted.

RESULTS

A total of 140 studies were included. Compared with saline, MIA injections caused significantly higher pain intensity for WBD and PWT. Dose-response relationships between different doses of MIA and pain intensity were observed (P-for-trend<0.05). A pronounced increase in pain occurred from day 0 to day 7, but the uptrend ceased between day 7 and day 14, after which the pain intensity continued to rise and reached the maximum by day 28.

CONCLUSIONS

Pain intensity after intra-articular MIA injection increased in a dose-dependent manner and the pain trajectory manifested a specific pattern consistent with the pathological mechanisms of MIA-induced pain, providing possible clues for proper dose selection and timing of specific OA pain interventions.

Prescription patterns and predictors of unmet pain relief in patients with difficult-to-treat osteoarthritis in the Nordics: analyses from the BISCUITS study

OBJECTIVES

Osteoarthritis (OA) is one of the leading causes of disability worldwide. Pain is the most important symptom in OA, driving medical care, disability, reduced functionality, and decreased quality of life. The objective of this study was to describe prescription patterns of difficult-to-treat OA and explore possible predictors of unmet pain relief in Nordic patients.

METHODS

This observational cohort study included patients with a confirmed diagnosis of OA (index date) in specialty care in Sweden, Norway, Finland and Denmark between 1 January 2011 and 31 December 2012 who were followed for up to 5 years. Four subgroups were pre-defined to characterize difficult-to-treat OA: (1) ≥2 chronic comorbidities in the 3-year pre-index period; (2) top 10% of healthcare resource users, 1-year post-index; (3) ≥3 types of prescription pain medications during pre-index period to first year post-index, with ≥30 days between types; (4) having a contraindication to a nonsteroidal anti-inflammatory drug (NSAID). Patient characteristics, prescription patterns and predictors of unmet pain relief (defined as persistent opioid use, using several types of opioids or long-term NSAID use) were analyzed.

RESULTS

We identified 288,174 OA patients and the average age was 63.5 years at time of diagnosis and 58% of them were female. After 5 years, 35-50% of the patients defined as 'difficult-to-treat' had ≥1 prescription of opioids, compared to 20-25% of all OA patients (p-value <0.05). Comorbidities and disability pension were strong predictors of unmet pain relief (p-value <0.001).

CONCLUSIONS

This study shows a substantial use of pain medications (NSAID and opioids) in difficult-to-treat OA patients. These findings suggest that pain may be inadequately managed in a considerable number of patients with OA, particularly those with contraindications to an NSAID. A high comorbid and socioeconomic burden are relevant risk factors among patients who continue to use opioids for a long period of time.

Physician and patient perceptions of surgical procedures for osteoarthritis of the knee in the United States, Europe, and Japan: results of a real-world study

BACKGROUND

Osteoarthritis (OA) is the most common form of arthritis, with the knee being the joint most frequently affected, and symptomatic knee OA affecting around one quarter of the general population. For patients who do not respond to non-pharmacologic or pharmacologic treatment, surgery is a recommended option. The objectives of this study were to compare the willingness of patients with knee OA to undergo surgery, together with reasons for delaying surgery, and factors affecting successful outcomes.

METHODS

A point-in-time survey was conducted in 729 primary care physicians, rheumatologists, orthopedic surgeons, and 2,316 patients with knee OA across three geographical regions: Japan, the United States (US), and Europe (EUR: France, Spain, Italy, Germany, and the United Kingdom), in order to garner their perceptions of knee surgery. Regression models were used to identify factors that might affect patients' and physicians' perceptions of surgery, including severity of OA (mild/moderate/severe), number of affected joints, surgery status, and willingness to undergo or delay surgery.

RESULTS

Baseline demographics were similar between US and EUR, although patients in Japan were more likely to be female, older, and only 7% in fulltime employment. We found that few patients with end-stage knee OA, across all regions, but particularly Japan, were willing to undergo surgery (Japan 17%, US 32%, EUR 38%), either through fear, or the lack of awareness of the risk/benefits. Moreover, surgeons are prepared to delay surgery in elderly or unwilling patients, due to their dissatisfaction with the outcome, and may defer surgery in younger patients due to the need for future revision. We also identified a disconnect between physicians, of whom over 80% consider improved functioning to be the most important outcome of surgery, and patients, who seek pain relief (Japan 60%, US 35%, EUR 14%). Since physicians across all regions considered pain reduction to be an indication of surgery success (Japan 27%, US 47%, EUR 43%), this may indicate a need for improved communication to patients on the potential benefits of surgery.

CONCLUSION

Managing the expectations of patients undergoing surgery remains an important goal in the treatment of knee OA and may help guide physician choice.

Efficacy, General Safety, and Joint Safety of Tanezumab in Japanese Patients with Osteoarthritis: Subgroup Analyses from Two Randomized, Phase 3 Studies

INTRODUCTION

Tanezumab is a monoclonal antibody against nerve growth factor that is under investigation for the treatment of osteoarthritis (OA) pain. We conducted subgroup analyses of two randomized phase 3 studies to summarize efficacy, general safety, and adjudicated joint safety of tanezumab in Japanese patients with moderate-to-severe OA.

METHODS

In Study 1 (NCT02528188), patients received subcutaneous tanezumab 2.5 mg or 5 mg every 8 weeks or daily oral nonsteroidal anti-inflammatory drugs (NSAID) for 56 weeks. The co-primary efficacy endpoints were change from baseline in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Pain subscale score and WOMAC Physical Function subscale score at Week 16 (overall study and Japan-specific endpoints) as well as Patient Global Assessment (PGA)-OA score at Week 16 (overall study endpoint only). In Study 2 (NCT02709486), patients received subcutaneous tanezumab 2.5 mg, 5 mg, or placebo every 8 weeks for 24 weeks. Safety monitoring included adjudicated composite joint safety endpoint (CJSE) including rapidly progressive osteoarthritis type 1 (RPOA1), RPOA2, primary osteonecrosis, pathological fracture, or subchondral insufficiency fracture.

RESULTS

For Study 1, Japanese patients (n = 200) treated with tanezumab 2.5 mg and 5 mg showed numerically greater improvements in WOMAC Pain, WOMAC Physical Function, and PGA-OA scores versus NSAID at Week 16. Incidences of treatment-emergent adverse events were generally similar between tanezumab 2.5 mg, 5 mg, and NSAID groups. In the integrated safety analysis (Studies 1 + 2; n = 306), ten patients were adjudicated to have a component of CJSE: RPOA1 [tanezumab 2.5 mg (n = 2), tanezumab 5 mg (n = 5)], RPOA2 [tanezumab 2.5 mg (n = 1), tanezumab 5 mg (n = 1)], or primary osteonecrosis [tanezumab 2.5 mg (n = 1)]. Time-adjusted adjudicated rates of RPOA1 and RPOA2 were higher with tanezumab than NSAID or placebo and increased with dose of tanezumab.

CONCLUSION

Observations from the Japanese subgroup were generally consistent with the overall study populations.

Prevalence of and Risk Factors for Prescription Opioid Misuse, Abuse, Diversion and Doctor Shopping in Japan: A Survey Study

INTRODUCTION

Opioid use disorder is a global problem. Although opioid analgesics are prescribed less frequently in Japan than in many other countries, the rate of aberrant prescription opioid-taking behaviors in Japan is unknown.

METHODS

An internet survey was conducted to estimate the prevalence of and risk factors for prescription opioid misuse, abuse, diversion and doctor shopping in Japanese subjects with chronic pain who had been prescribed opioid analgesics.

RESULTS

The proportion of respondents (n = 387) who reported opioid misuse was 45.5% (95% confidence interval [CI]: 40.4-50.6); rates were: 24.6% (95% CI: 20.3-29.2) for abuse; 15.0% (95% CI: 11.6-19.0) for diversion; and 10.6% (95% CI: 7.7-14.1) for doctor shopping. Aberrant prescription opioid-taking behaviors were higher in participants with chronic post-cancer treatment pain (misuse, 64.2%; abuse, 52.2%) or chronic cancer pain (misuse, 57.4%; abuse, 26.2%) than in those with chronic noncancer pain (misuse, 37.8%; abuse, 17.0%). Younger age, male sex, smoking, habitual drinking, diagnosis of psychiatric disease, use of opioids other than tramadol, and use of opioids for chronic post-cancer treatment pain and chronic cancer pain were identified as risk factors for aberrant prescription opioid-taking behaviors.

CONCLUSION

Even in Japan, which has not experienced the surge in opioid consumption documented in other countries, aberrant prescription opioid-taking behaviors were observed. When prescribing opioid analgesics, universal precautions should always be taken for both cancer and non-cancer patients.

TRIAL REGISTRATION

UMIN000041788.

Cost-Effectiveness Analysis of the Treatment Strategies with or without Opioid Medications in Surgery-Eligible Patients with Osteoarthritis in Japan

AIM

The aim of this study was to evaluate the cost effectiveness of treatment strategies without opioid medications (non-opioid treatment strategy) versus strategies with opioid medications (opioid treatment strategy) among surgery-eligible patients with osteoarthritis (OA) of the knee or hip in Japan.

MATERIALS AND METHODS

We built a Markov cohort model to evaluate outcomes for the treatment strategies in surgery-eligible patients aged ≥ 65 years with OA of the knee or hip in Japan. The opioid treatment strategy as an intervention includes a health state with opioid medication in the treatment pathway. On the other hand, for the non-opioid treatment strategy, there is no health state with opioid medication. A targeted literature review and database analysis were conducted to identify and define the values of the variables included in the model. The time horizon was set to 30 years, and a 2% discount was applied for cost and quality-adjusted life-years (QALYs). Sensitivity analysis and scenario analysis were performed in the model. The outcomes were QALYs and the incremental cost-effectiveness ratio (ICER).

RESULTS

In the base-case analysis, the non-opioid treatment strategy was dominant over the opioid treatment strategy and associated with an incremental cost and QALYs of - 53,878 JPY (- 499 USD) and 0.03 QALYs, respectively, in patients with knee OA, and - 54,129 JPY (- 502 USD) and 0.02 QALYs, respectively, in patients with hip OA. One-way sensitivity analysis showed the ICER was most sensitive to the QALY for opioid monotherapy. Probabilistic sensitivity analyses showed a high degree of uncertainty associated with the results.

LIMITATIONS

Study limitations included assumptions related to transition probabilities of the health states, and a lack of Japanese-specific data for transition probabilities, incidence of adverse events and utility values.

CONCLUSIONS

This study suggests that the non-opioid treatment strategy is cost effective compared with the opioid treatment strategy in the management of surgery-eligible patients with OA of the knee or hip. However, this final conclusion may not be accurate as the methodology is heavily reliant on assumptions.

Safety risk associated with use of nonsteroidal anti-inflammatory drugs in Japanese elderly compared with younger patients with osteoarthritis and/or chronic low back pain: A retrospective database study

Purpose

This study aimed to assess the safety risks associated with using nonsteroidal anti‐inflammatory drugs (NSAIDs) in elderly patients (≥65 years) compared with younger patients (<65 years) with osteoarthritis (OA) and/or chronic low back pain (CLBP).

Methods

A retrospective analysis was conducted on anonymized claims data of patients prescribed NSAIDs for OA and/or CLBP from 2009 to 2018 using hospital‐based administrative database—Medical Data Vision (MDV). The key outcome was the incidence of developing gastrointestinal (GI), renal, and acute myocardial infarction (AMI) that are well‐known events associated with NSAID use.

Results

Of 288,715 patients included, 23.7%, 60.5%, and 15.8% had OA, CLBP, or both, respectively. Elderly patients used non‐oral NSAIDs more frequently than oral NSAIDs (57.8% and 38.7%, respectively), whereas younger patients showed comparable use (50.7% and 52.8%, respectively). The incidence of events per 10,000 person‐years (95% CI) was higher in the elderly than in younger patients: GI, 29.68(27.67–31.68) vs. 16.61(14.60–18.63); renal, 124.77(120.56–128.99) vs. 39.88(36.72–43.03); and AMI, 27.41(25.48–29.35) vs. 10.90(9.27–12.53), respectively. After adjusting for covariates, the increase in risk for these events was seen in patients >70 years compared with younger patients (18–30 years) and was remarkable in patients >80 years with 2‐fold, 10‐fold, and 7‐fold higher risk for developing GI, renal, and AMI events, respectively.

Conclusion

Risk for developing NSAID‐associated events was higher in the elderly; particularly, renal and AMI events that remarkably increased in patients >80 years. To reduce them, NSAIDs should be prescribed at the lowest effective dose for the shortest duration possible.

Unmet Needs in the Osteoarthritis Chronic Moderate to Severe Pain Management in Spain: A Real Word Data Study

INTRODUCTION

Patients with moderate or severe pain due to osteoarthritis (OAP) usually undergo pharmacological treatment with NSAIDs and/or opioids. Many of them do not get adequate pain relief because of intolerances, contraindications and the ineffectiveness of these treatments. The main objective of the present study was to quantify the group of OAP patients who are inadequately treated for their pain in routine clinical practice in Spain and to describe the prescription flow of these patients.

METHODS

This was a non-interventional, retrospective cohort study conducted using the IQVIA's electronic medical records database in Spain. Patients with osteoarthritis (OA), aged ≥ 15 years and receiving any pain treatment during 12 out of 24 months between 1 October 2017 and 30 September 2019 were studied. Assumptions were made to identify patients with contraindication or intolerance to NSAIDs or opioids and those who failed NSAID or opioid therapy.

RESULTS

Out of 136,556 patients with OA, 29,886 had moderate-to-severe pain, which extrapolated to the general population in Spain represents 1,541,286 OAP patients. Mean age (SD) of OAP patients was 75 (12.8) years, and 73.8% were female; 52.8% were treated with NSAIDs and/or weak opioids. There were were 16,748 OAP patients (56.08%) (extrapolated figure 838,620) with one or more conditions associated with being inadequately treated (contraindication, intolerance or failed NSAID and/or opioid therapy). In most OAP patients (91%) pain treatment was initiated by the general practitioner (GP) alone. Considering overall successive therapy lines, after the first prescription, pain drugs were prescribed by a GP in 61% of the cases, by a specialist in 20% and by both in 18%.

CONCLUSION

More than half of the patients with OA in Spain have unsatisfactory pain control. Pain drugs are mainly prescribed by GPs, and specialists (traumatologists, rheumatologists, physiatrists and pain management specialists) are not very involved in the management of OAP patients.

The Cut-off Value of Physical Activity for Undergoing Total Knee Arthroplasty in Patients with Knee Osteoarthritis

BACKGROUND

We aimed to determine a cut-off value for physical activity (PA), measured using an accelerometer, between patients with knee osteoarthritis (OA) who decided to undergo total knee arthroplasty (TKA) and those who continued conservative treatment.

METHODS

Forty-two participants were assigned to either a TKA group or a non-TKA group (21 per group). They were instructed to wear an accelerometer throughout the day. Average daily steps (steps/day), average daily time of light PA (LPA) (min/day), and average daily time of moderate-to-vigorous PA (MVPA) (min/day) were measured for seven days. Variables between the two groups were compared using univariate analyses, and then a stepwise logistic regression was conducted to determine which variables best correlated with undergoing TKA. The PA cut-offs were analysed using the receiver operating characteristic curve.

RESULTS

Pain severity (p = 0.002), KL grade (p = 0.001), and MVPA (p = 0.012) differed significantly between the groups. The most useful cut-off value was 5.84 (min/day) for MVPA (AUC = 0.773), although only pain severity and KL grade were found to be significant contributors to undergoing TKA.

CONCLUSIONS

Our results revealed there was a significant decrease in PA levels (MVPA cut-off, 5-6 min/day) in the TKA group compared with the non-TKA group.

Treating osteoarthritis pain: mechanisms of action of acetaminophen, nonsteroidal anti-inflammatory drugs, opioids, and nerve growth factor antibodies

Osteoarthritis (OA) is a common difficult-to-treat condition where the goal, in the absence of disease-modifying treatments, is to alleviate symptoms such as pain and loss of function. Acetaminophen, nonsteroidal anti-inflammatory drugs (NSAIDs), and opioids are common pharmacologic treatments for OA. Antibodies directed against nerve growth factor (NGF-Abs) are a new class of agents under clinical investigation for the treatment of OA. This narrative review describes (and uses schematics to visualize) nociceptive signaling, chronification of pain, and the mechanisms of action (MOAs) of these different analgesics in the context of OA-related pain pathophysiology. Further, the varying levels of efficacy and safety of these agents observed in patients with OA is examined, based on an overview of published clinical data and/or treatment guidelines (when available), in the context of differences in their MOAs.

A Retrospective Database Study of Gastrointestinal Events and Medical Costs Associated with Nonsteroidal Anti-Inflammatory Drugs in Japanese Patients of Working Age with Osteoarthritis and Chronic Low Back Pain

CONTEXT

The real-world burden of gastrointestinal (GI) events associated with the use of nonsteroidal anti-inflammatory drugs (NSAIDs) in Japanese patients with osteoarthritis (OA) and/or chronic low back pain (CLBP) remains unreported.

OBJECTIVE

To assess the incidence and economic burden of NSAID-induced GI events by using data from large-scale real-world databases.

METHODS

We used the Japanese Medical Data Center database to retrospectively evaluate anonymized claims data of medical insurance beneficiaries employed by middle- to large-size Japanese companies who were prescribed NSAIDs for OA and/or CLBP between 2009 and 2018.

RESULTS

Overall, 180,371 patients were included in the analysis, of whom 32.9% had OA, 53.8% had CLBP, and 13.4% had both OA and CLBP. NSAIDs were administered as first-line analgesics to 161,152 (89.3%) of the patients in the sample, in oral form to 90.3% and as topical patches to 80.4%. A total of 65.1% used combined oral/topical patches. Of the 21.0% of patients consistently using NSAIDs (percentage of days supplied ≥70%), 54.5% received patches. A total of 51.5% patients used NSAIDs for >1 to ≤6 months. The incidence of GI events was 9.97 per 10,000 person-years (95% confidence interval: 8.92-11.03). The risk of developing GI events was high in elderly patients and patients with comorbidities and remained similar for patients receiving oral vs. topical NSAIDs. Longer treatment duration and consistent NSAID use increased the risk of GI events. The cost (median [interquartile range]) of medications (n = 327) was US$ 80.70 ($14.10, $201.40), that of hospitalization (n = 33) was US$ 2,035.50 ($1,517.80, $2,431.90), and that of endoscopic surgery (n = 52) was US$ 418.20 ($418.20, $418.20).

CONCLUSION

NSAID-associated GI toxicity imposes a significant health and economic burden on patients with OA and/or CLBP, irrespective of whether oral or topical NSAIDs are used.

Pain Pharmacotherapy in a Large Cohort of Patients with Osteoarthritis: A Real-World Data Analysis

INTRODUCTION

There is limited evidence on the consumption of analgesics in real-world large cohorts of patients with osteoarthritis (OA), especially in those with comorbidities. We aimed to characterize the use of pharmacological analgesic treatments, evaluate standardized comorbidity rates, and assess treatment trends. Our hypotheses were: (1) OA patients generally consume low and inconsistent pharmacological analgesic treatments; (2) analgesic treatment is often non-congruent with comorbidity-related safety concerns.

METHODS

The study was carried out at the second largest health maintenance organization in Israel. Members aged 18 years or above who were diagnosed with OA before December 31, 2018, were included. Information was obtained from the members' electronic medical record (EMR) including data on dispensed prescriptions, which were used to estimate analgesic consumption.

RESULTS

A total of 180,126 OA patients were included in our analyses; analgesics were dispensed to 64.2% of the patients, with oral NSAIDs and opioids dispensed to 34.1 and 22.9% of the OA population, respectively. Analgesic use increased with time lapsed from OA diagnosis (p < 0.001), up to a median of 59 days covered (IQR, 20-175) after 21 years. Rates of most comorbidities in the OA population were higher compared to the MHS general population. Patients with comorbidities used more NSAIDs and opioids compared to those without them.

CONCLUSIONS

Most OA patients use analgesics, usually oral NSAIDs. Analgesic use remains relatively low throughout the years, indicating that many OA patients are not being treated pharmacologically for pain on a regular basis. Despite having higher rates of several comorbidities compared to MHS general population, many OA patients are still treated with analgesics that can be associated with a worsening in comorbidity.

Burden of Renal Events Associated with Nonsteroidal Anti-inflammatory Drugs in Patients with Osteoarthritis and Chronic Low Back Pain: A Retrospective Database Study

INTRODUCTION

Nonsteroidal anti-inflammatory drugs (NSAIDs) have long-term benefits but are limited by side effects. We assessed the health and economic burden of renal events associated with NSAID use in patients with osteoarthritis (OA) and/or chronic low back pain (CLBP).

METHODS

This retrospective, large-scale, medical claims database study of Japanese patients receiving NSAIDs for OA and/or CLBP between 2009 and 2018 assessed the incidence of renal events and effect of treatment duration, mode of administration, and usage consistency of NSAIDs.

RESULTS

Of 180,371 patients, NSAIDs were prescribed as first-line analgesics in 89.3%. Incidence per 10,000 person-years (95% confidence interval [CI]) for renal events was 23.46 (21.84-25.08) and for progression of chronic kidney disease (CKD) was 267.12 (189.93-344.32). Longer treatment duration (> 1 to  ≤ 3 years, risk ratio [RR] 1.32, 95% CI 1.12-1.54; P = 0.0007; > 3 to  ≤ 5 years, RR: 1.38, 95% CI 1.04-1.84; P = 0.0254 vs. < 1 year) and consistent use (RR: 1.24, 95% CI 0.99-1.55; P = 0.0595) increased the risk of renal events but the latter did not reach statistical significance. The risk was similar in patients using patch/oral NSAIDs and high in elderly patients and in those with diabetes, hypertension, and other cardiovascular disease. Following a renal event, median 1-year cost of drug treatment was $27.90; hospitalization, $1779.40; and dialysis, $33,018.40.

CONCLUSIONS

Risk of renal events significantly increased with prolonged and consistent NSAID use (irrespective of mode of administration), with age, and in patients with certain comorbidities. Careful NSAID use is recommended in patients with CKD and those at high risk for CKD.

Database Analysis on the Relationships Between Nonsteroidal Anti-inflammatory Drug Treatment Variables and Incidence of Acute Myocardial Infarction in Japanese Patients with Osteoarthritis and Chronic Low Back Pain

Introduction

We aimed to analyze the relationships between nonsteroidal anti-inflammatory drug (NSAID) treatment variables and the incidence of acute myocardial infarction (AMI) in Japanese patients with osteoarthritis (OA) and chronic low back pain (CLBP) using the data from a large-scale, real-world database.

Methods

We retrospectively analyzed anonymized claims data from the Japanese Medical Data Center of medical insurance beneficiaries who were prescribed NSAIDs for OA and/or CLBP from 2009 to 2018.

Results

Of 180,371 patients, 89.3% received NSAIDs as first-line analgesics (oral, 90.3%; patch, 80.4%; other transdermal drugs, 24.0%). Incidence of AMI was 10.27 per 10,000 person-years (95% confidence interval 9.20–11.34) in the entire study population. There was a trend towards increased risk in patients using NSAIDs for more than 5 years (P = 0.0784) than in those using NSAIDs for less than 1 year. Risk of AMI significantly increased with age and comorbidities of diabetes and cardiovascular disease (CVD). The risk for AMI was similar for patients who consistently used NSAIDs compared to those using them intermittently and patients who used patch compared to oral NSAIDs. Elderly patients used NSAIDs more consistently and used NSAID patches more frequently.

Conclusion

In Japanese patients with OA and CLBP, we saw a trend of increased risk for AMI in patients using NSAIDs for more than 5 years. Elderly patients had a higher prevalence of diabetes, hypertension, and other CVD which increased the risk of AMI. Although NSAID patches were preferred to oral NSAIDs in elderly patients, risk for AMI was similar between the two modalities. Therefore, we suggest using NSAIDs carefully, especially in elderly patients and those at risk of developing CVD.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-021-01629-6.

Long-Term Pain Management and Health Care Resource Use Among an Employed Population in Japan with Knee Osteoarthritis Combined with Low Back Pain

Objective

Assess long-term comorbidity burden and pain management patterns among working-age patients with knee osteoarthritis (KOA) only without low back pain (LBP) (KOA-noLBP) and patients with KOA plus LBP (KOA+LBP) in Japan.

Methods

Retrospective claims data analyses were conducted on data from the Japan Medical Data Center (JMDC) database. Adult patients (≥40 years) with a diagnosis of knee osteoarthritis (KOA) (January 1, 2011–December 31, 2012) and 5 years of follow-up were evaluated. The first claim with a KOA diagnosis defined the index date. Longitudinal pain management patterns were assessed in both cohorts.

Results

Overall, 1,828 patients met study criteria (717 with KOA-noLBP; 1,111 with KOA+LBP). The mean age of patients with KOA-noLBP was 52.1 years, and that of patients with KOA+LBP was 53.1 years, with more females in the KOA+LBP cohort (49.4% vs. 55.0%). Regardless of cohort, >90% of patients received pharmacological intervention during the 5-year follow-up period. The most common regimen first received was either topical or oral nonsteroidal anti-inflammatory drugs. A higher mean number of pharmaceutical treatments were received by patients in the KOA+LBP cohort (3.6) than by patients in the KOA-noLBP cohort (2.7) during the follow-up period. Regardless of cohort, most of the direct medical cost was derived from medication.

Conclusion

This study demonstrates that a greater proportion of the JMDC population of working individuals with KOA were comorbid with LBP and received pain-related treatment in the long-term perspective relative to patients with KOA without LBP. Appropriate pain management for both KOA and LBP would be key for effective resource utilization in an aging society facing socioeconomic burdens

Open-Label Placebo Trial among Japanese Patients with Chronic Low Back Pain

Background

The aim of this study was to confirm the effectiveness of open-label placebo (OLP) in Japanese patients with chronic low back pain (CLBP), similar to previous reports, and to investigate its short- and medium-term effects in this study population.

Methods

Fifty-two patients with CLBP were randomized into a treatment as usual (TAU) group (n = 26) or an OLP + TAU group (n = 26) for 12 weeks. The TAU included advice to remain active and exercise in conjunction with recent psychological education based on a self-management strategy. In contrast, participants in the OLP + TAU group were instructed to take two OLP capsules a day. Outcome measures were assessed at baseline and at weeks 3 and 12 using the Roland–Morris Disability Questionnaire (RMDQ), Numerical Rating Scale (NRS) for pain intensity, and the Timed-Up-and-Go (TUG) test. Difference in outcomes between the two groups was compared at the two follow-up points.

Results

Although all participants completed the 3-week follow-up, four patients (two in each group) were lost to follow-up beyond week 3. There were no significant intergroup differences in changes in the RMDQ score (p=0.40), pain-NRS score (p=0.19), and TUG time (p=0.98) at week 3. Two-way repeated measure analyses of covariance showed significant time-course effects but did not show group effects or any interactions between the time-course and group in terms of the RMDQ score. However, it did not show any effects in the pain-NRS score and TUG time at week 12.

Conclusions

The OLP + TAU group showed no superior findings in comparison with the TAU group after 3 weeks and 12 weeks for Japanese patients with CLBP. Nonetheless, significant improvements in functional disability were observed in both groups.

Treatment and Healthcare Cost Among Patients with Hip or Knee Osteoarthritis: A Cross-sectional Study Using a Real-world Claims Database in Japan Between 2013 and 2019

BACKGROUND AND OBJECTIVES

The guidelines for osteoarthritis (OA) treatment recommend different therapies including pharmacotherapy, and several analgesic options are available for pain management. In Japan, research on hip and knee OA treatment trends is scarce and OA-related healthcare costs are unknown. Therefore, this study aimed to examine the treatment and healthcare cost trends among Japanese patients with hip or knee OA.

METHODS

This was a cross-sectional study held between 2013 and 2019, using a medical claims database. The demographic and treatment characteristics of hip or knee OA patients for each year were descriptively analyzed and the medians for healthcare utilization and all-cause healthcare costs were calculated.

RESULTS

The yearly mean age of 59,218 hip OA and 270,722 knee OA patients ranged from 66.3 to 68.6 years and 71.1 to 73.1 years, respectively. The prevalence of comorbidities was higher in knee OA than hip OA. In both groups, > 70% of patients were female, and the most common treatment was pain-related medication. In hip OA, topical and systemic nonsteroidal anti-inflammatory drugs (NSAIDs) were mostly used throughout the study period (34.1-41.4% and 32.0-40.3%, respectively). Similarly, in knee OA, topical and systemic NSAIDs were used in 58.3-63.3% and 36.5-46.0% patients, respectively. Increase in the use of acetaminophens (10.9% in hip OA and 10.2% in the knee OA) and weak opioids (3.7%, and 3.4%, respectively) from 2013 to 2019 were observed. Most patients were treated as outpatients in both groups. The median all-cause healthcare costs were approximately 35,000 JPY for hip OA and 74,000 JPY for knee OA.

CONCLUSIONS

Although a considerable change in total healthcare cost was not observed in our study, the contents of medical treatment and cost breakdown were greatly altered due to the treatment and cost for OA itself, and the treatment and cost for comorbidities. Similar studies to investigate such a trend may help predict necessary resources and social needs. Thus, further investigation utilizing other databases is needed.