Genomic heterozygosity is associated with a lower risk of osteoarthritis.

BACKGROUND: Genomic heterozygosity has been shown to confer a health advantage in humans and play a protective role in complex diseases. Given osteoarthritis (OA) is a highly polygenic disease, we set out to determine if an association exists between OA and genomic heterozygosity. RESULTS: End-stage knee and hip OA patients and healthy controls were recruited from the Newfoundland and Labrador (NL) population. The Arthritis Research UK Osteoarthritis Genetics (arcOGEN) consortium database was utilized as a replication cohort. DNA was extracted from blood samples and genotyped. Individual rates of observed heterozygosity (HetRate) and heterozygosity excess (HetExcess) relative to the expected were mathematically derived, and standardized to a z-score. Logistic regression modeling was used to examine the association between OA and HetRate or HetExcess. A total of 559 knee and hip OA patients (mean age 66.5 years, body mass index (BMI) 33.7 kg/m2, and 55% females) and 118 healthy controls (mean age 56.4 years, BMI 29.5 kg/m2, and 59% female) were included in the NL cohort analysis. We found that OA had an inverse relationship with HetRate and HetExcess with odds ratios of 0.64 (95% CI: 0.45-0.91) and 0.65 (95% CI: 0.45-0.93) per standard deviation (SD), respectively. The arcOGEN data included 2,019 end-stage knee and hip OA patients and 2,029 healthy controls, validating our findings with HetRate and HetExcess odds ratios of 0.60 (95% CI: 0.56-0.64) and 0.44 (95% CI: 0.40-0.47) per SD, respectively. CONCLUSIONS: Our results are the first to clearly show evidence, from two separate cohorts, that reduced genomic heterozygosity confers a risk for the future development of OA.

Urinary incontinence in middle-aged and older women with hip and knee osteoarthritis: An outpatient study of frequency and risk factors.

AIMS: To investigate the frequency and the factors associated with urinary incontinence (UI) in a sample of middle-aged and older women with lower limb osteoarthritis (OA). METHODS: Women aged 50 years or older with clinical hip/knee OA diagnoses were recruited for this cross-sectional study. Self-reported UI and type, sociodemographic characteristics, medical conditions, physical activity level, anthropometric and body composition measurements, muscle strength, and physical function were assessed. Uni and multivariable logistic regression were used to investigate the factors associated with UI. RESULTS: Among 100 middle-aged and older women (mean 67.27 ± 8.77 SD years), 67% reported UI. In the UI group, 33% reported stress UI, 36% reported urgency UI, and 31% reported mixed UI. In the univariate analysis, age, level of physical activity, pulmonary disease, number of medications, body mass index (BMI), number of deliveries, and activity limitation were significantly associated with UI. In the multivariable analysis, older age (60-69 years OR: 4.91, 95% CI: 1.25-19.36; ≥70 years OR: 8.06, 95% CI: 1.96-33.22), compared to 50-59 years, morbid obesity (OR: 14.10, 95% CI: 1.36-146.48), compared to BMI < 30 kg/m2 , and activity limitation (OR: 5.31, 95% CI: 1.61-17.54), assessed as short physical performance battery ≤8, remained significantly associated with UI. CONCLUSIONS: UI was highly frequent among middle-aged and older women with hip/knee OA. Older age, activity limitation, and morbid obesity were independently associated with UI. Interventions targeting physical function and weight management must be considered to prevent and treat UI in this population.

Causal relationship between sarcopenia with osteoarthritis and the mediating role of obesity: a univariate, multivariate, two-step Mendelian randomization study.

BACKGROUND: Recent genetic evidence supports a causal role for sarcopenia in osteoarthritis, which may be mediated by the occurrence of obesity or changes in circulating inflammatory protein levels. Here, we leveraged publicly available genome-wide association study data to investigate the intrinsic causal relationship between sarcopenia, obesity, circulating inflammatory protein levels, and osteoarthritis. METHODS: In this study, we used Mendelian randomization analyses to explore the causal relationship between sarcopenia phenotypes (Appendicular lean mass [ALM], Low hand-grip strength [LHG], and usual walking pace [UWP]) and osteoarthritis (Knee osteoarthritis [KOA], and Hip osteoarthritis [HOA]). Univariable Mendelian randomization (UVMR) analyses were performed using the inverse variance weighted (IVW) method, MR-Egger, weighted median method, simple mode, and weighted mode, with the IVW method being the primary analytical technique. Subsequently, the independent causal effects of sarcopenia phenotype on osteoarthritis were investigated using multivariate Mendelian randomization (MVMR) analysis. To further explore the mechanisms involved, obesity and circulating inflammatory proteins were introduced as the mediator variables, and a two-step Mendelian randomization analysis was used to explore the mediating effects of obesity and circulating inflammatory proteins between ALM and KOA as well as the mediating proportions. RESULTS: UVMR analysis showed a causal relationship between ALM, LHG, UWP and KOA [(OR = 1.151, 95% CI: 1.087-1.218, P = 1.19 × 10-6, PFDR = 7.14 × 10-6) (OR = 1.215, 95% CI: 1.004-1.470; P = 0.046, PFDR = 0.055) (OR = 0.503, 95% CI: 0.292-0.867; P = 0.013, PFDR = 0.027)], and a causal relationship between ALM, UWP and HOA [(OR = 1.181, 95% CI: 1.103-1.265, P = 2.05 × 10-6, PFDR = 6.15 × 10-6) (OR = 0.438, 95% CI: 0.226-0.849, P = 0.014, PFDR = 0.022)]. In the MVMR analyses adjusting for confounders (body mass index, insomnia, sedentary behavior, and bone density), causal relationships were observed between ALM, LHG, UWP and KOA [(ALM: OR = 1.323, 95%CI: 1.224- 1.431, P = 2.07 × 10-12), (LHG: OR = 1.161, 95%CI: 1.044- 1.292, P = 0.006), (UWP: OR = 0.511, 95%CI: 0.290- 0.899, P = 0.020)], and between ALM and HOA (ALM: OR = 1.245, 95%CI: 1.149- 1.348, P = 7.65 × 10-8). In a two-step MR analysis, obesity was identified to play a potential mediating role in ALM and KOA (proportion mediated: 5.9%). CONCLUSIONS: The results of this study suggest that decreased appendicular lean mass, grip strength, and walking speed increase the risk of KOA and decreased appendicular lean mass increases the risk of HOA in patients with sarcopenia in a European population. Obesity plays a mediator role in the occurrence of KOA due to appendicular lean body mass reduction.

Incidence of knee and hip joint replacement associated with cumulative exposure to physical factors at work.

BACKGROUND: Knee osteoarthritis (OA) has been quite consistently associated with high physical workload and specific physical factors at work, while for hip OA, fewer studies are available, which still indicate possible associations with heavy lifting and physical workload. The objective of the study was to assess the association between exposure to workplace physical factors and incidence of knee and hip arthroplasty, as markers of severe OA in these joints. METHODS: The study population was composed of employees 25-60 years who participated in the Turin 2011 census. For each job held since 1995, exposure to physical factors was assigned to individuals in the cohort through a Job-Exposure Matrix constructed from the Italian O*NET database. Using Poisson regression models, the incidence of knee and hip arthroplasty for OA, identified through hospitalizations from 2012 to 2018, was examined in relation to cumulative exposure to 7 different physical hazards and a composite indicator of physical workload constructed from 17 physical factors (Ergo-Index). RESULTS: The risk of knee OA was significantly increased in the highest cumulative exposure quartile of physical workload (incidence rate ratio = 1.98, 95% confidence interval: 1.24-3.16) and of all single hazards examined, compared to the lowest quartile, with significant trends in risk with increasing exposure. In contrast, no association was found with hip OA, whose relative risks were close to or below one in all higher-exposure quartiles of physical workload and of each single hazard. CONCLUSIONS: Our results indicate that exposure to physical hazards at work increases the likelihood of developing knee OA, but not hip OA.

Associations of current and childhood socioeconomic status and health outcomes amongst patients with knee or hip osteoarthritis in a Mexico City family-practice setting.

OBJECTIVES: To examine the association of current and childhood socioeconomic status (SES) with patient-reported functional status, quality of life and disability in patients with knee or hip osteoarthritis (OA). METHODS: Cross-sectional study amongst individuals seeking care for any medical reason in a primary care family-practice clinic in Mexico City. We included individuals with self-reported doctor-diagnosed arthritis, recruited through waiting-room posters and invitations by treating family physicians. We administered a survey using validated Spanish language versions of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), the Osteoarthritis of Lower Limbs and Quality of Life (AMICAL), and the Stanford Health Assessment Questionnaire-Disability Index (HAQ-DI). To estimate current and childhood SES, we collected data on education level and occupation type for both the patient and their parents, as well as using a validated tool to estimate income quintile. RESULTS: We recruited 154 patients and excluded 8 patients. There was a high correlation between outcome scores. Estimated income and education levels were correlated with WOMAC, AMICAL and HAQ-DI scores, and significant differences were found in all scores by occupation type. The associations for current SES variables and outcome scores remained significant independently of age, sex, BMI, and presence of diabetes or hypertension, and were largely explained by current income in mutually adjusted models. Childhood SES - in particular as measured through maternal education - was best correlated with AMICAL scores, though its effect seemed largely mediated by its association with current SES. CONCLUSIONS: Current Socioeconomic Status impacts functional status, quality of life and disability amongst OA patients in Mexico City. The WOMAC, AMICAL and HAQ-DI scores correlate with each other and are all potentially useful markers of disease severity. More research is needed to elucidate the relationships between childhood SES and OA outcomes. Awareness of life-course SES may be useful in identifying patients at risk for worse outcomes.

Eligibility for knee arthroplasty is associated with increased risk of acquired hallux valgus - a Mendelian randomized study.

OBJECTIVE: Clinically, it has been found that patients undergoing knee replacement have a high incidence of concomitant hallux valgus. In this study, we analyzed whether patients with osteoarthritis who underwent surgery and those patient who did not have surgery had an increased risk of hallux valgus by Mendelian randomization and performed reverse causal analysis. DESIGN: Genomewide association study (GWAS) data for osteoarthritis, categorized by knee arthritis with joint replacement, knee arthritis without joint replacement, hip arthritis with joint replacement, and hip arthritis without joint replacement.And acquired hallux valgus were downloaded for Mendelian randomized studies. MR analysis was performed using inverse variance-weighted (IVW), weighted median, and MR-Egger methods. MR-egger regression, MR pleiotropic residuals and outliers (MR-presso), and Cochran's Q statistical methods were used to evaluate heterogeneity and pleiotropy. RESULTS: The IVW results indicate that, compared to healthy individuals, patients who meet the criteria for knee osteoarthritis joint replacement surgery have a significantly higher risk of acquired hallux valgus. There were no significant causal relationships found for the remaining results. No significant heterogeneity or multiplicity was observed in all the Mr analyses. CONCLUSION: Our study supports the increased risk of acquired hallux valgus in patients eligible for knee replacement. There is necessary for clinicians to be concerned about the hallux valgus status of patients undergoing knee arthroplasty.

Annual epidemiological and health insurance disease burden of hip osteoarthritis in Hungary based on nationwide data.

BACKGROUND: Health services utilization related to hip osteoarthritis imposes a significant burden on society and health care systems. Our aim was to analyse the epidemiological and health insurance disease burden of hip osteoarthritis in Hungary based on nationwide data. METHODS: Data were extracted from the nationwide financial database of the National Health Insurance Fund Administration (NHIFA) of Hungary for the year 2018. The analysed data included annual patient numbers, prevalence, and age-standardized prevalence per 100,000 population in outpatient care, health insurance costs calculated for age groups and sexes for all types of care. Patients with hip osteoarthritis were identified using code M16 of the International Classification of Diseases (ICD), 10th revision. Age-standardised prevalence rates were calculated using the European Standard Population 2013 (ESP2013). RESULTS: Based on patient numbers of outpatient care, the prevalence per 100,000 among males was 1,483.7 patients (1.5%), among females 2,905.5 (2.9%), in total 2,226.2 patients (2.2%). The age-standardised prevalence was 1,734.8 (1.7%) for males and 2,594.8 (2.6%) for females per 100,000 population, for a total of 2,237.6 (2.2%). The prevalence per 100,000 population was higher for women in all age groups. In age group 30-39, 40-49, 50-59, 60-69 and 70 + the overall prevalence was 0.2%, 0.8%, 2.7%, 5.0% and 7.7%, respectively, describing a continuously increasing trend. In 2018, the NHIFA spent 42.31 million EUR on the treatment of hip osteoarthritis. Hip osteoarthritis accounts for 1% of total nationwide health insurance expenditures. 36.8% of costs were attributed to the treatment of male patients, and 63.2% to female patients. Acute inpatient care, outpatient care and chronic and rehabilitation inpatient care were the main cost drivers, accounting for 62.7%, 14.6% and 8.2% of the total health care expenditure for men, and 51.0%, 20.0% and 11.2% for women, respectively. The average annual treatment cost per patient was 3,627 EUR for men and 4,194 EUR for women. CONCLUSIONS: The prevalence of hip osteoarthritis was 1.96 times higher (the age-standardised prevalence was 1.5 times higher) in women compared to men. Acute inpatient care was the major cost driver in the treatment of hip osteoarthritis. The average annual treatment cost per patient was 15.6% higher for women compared to men.

An in-depth analysis of young adults with osteonecrosis secondary to developmental dysplasia of the hip who underwent total hip arthroplasty.

BACKGROUND: Patients with osteonecrosis of the femoral head secondary to DDH frequently require total hip arthroplasty (THA), but it is not well understood which factors necessitate this requirement. We determined the incidence of THA in patients who have osteonecrosis secondary to DDH and factors associated with need for THA. METHODS: We included patients who received closed or open reductions between 1995 and 2005 with subsequent development of osteonecrosis. We determined osteonecrosis according to Bucholz and Ogden; osteoarthritis severity (Kellgren-Lawrence), subluxation (Shenton's line); neck-shaft angle; and acetabular dysplasia (centre-edge and Sharp angles). We also recorded the number of operations of the hip in childhood and reviewed case notes of patients who received THA to describe clinical findings prior to THA. We assessed the association between radiographic variables and the need for THA using univariate logistic regression. RESULTS: Of 140 patients (169 hips), 22 patients received 24 THA (14%) at a mean age of 21.3 ± 3.7 years. Associated with the need for THA were grade III osteonecrosis (OR 4.25; 95% CI 1.70-10.77; p = 0.0019), grade IV osteoarthritis (21.8; 7.55-68.11; p < 0.0001) and subluxation (8.22; 2.91-29.53; p = 0.0003). All patients who required THA reported at least 2 of: severe pain including at night, stiffness, and reduced mobility. Acetabular dysplasia and number of previous operations were not associated with the need for THA. CONCLUSIONS: We identified a 14% incidence of THA by age 34 years in patients with osteonecrosis secondary to DDH. Grade III osteonecrosis (global involvement femoral head and neck) was strongly associated with THA, emphasising the importance to avoid osteonecrosis when treating DDH.

Anterior and posterior hip osteoarthritis: prevalence and potential value of CT compared to radiographs.

PURPOSE: To determine the added value of computed tomography (CT) to identify severe hip osteoarthritis (OA). MATERIALS AND METHODS: A retrospective query of all cases of hip or knee arthroplasty planning CTs between January 2018 and March 2022 was performed. Age, sex, and symptoms were collected from the medical record. CTs were evaluated for the degree of osteoarthritis and classified using an adapted Kellgren-Lawrence (KL) grading system in the anterior, posterior, superior, and superomedial hip. Frontal hip or pelvis radiographs within 1 year of the CT were also graded. RESULTS: There were 265 eligible hips in 178 subjects, age 66 ± 11 (range 31-93) years, with 85/178 (48%) males and 93/178 (52%) females, and 127/265 (48%) right and 138/265 (52%) left hips. The posterior hip joint was the most common location for grade 2/3 OA (20%), followed by superior hip joint (14%). Anterior or posterior grade 2/3 OA occurred concurrently with superior or superomedial grade 2/3 OA in 32/68 (47%) of hips. Grade 2/3 OA was detected on CT more commonly than on XR both in the superior (14 vs 8.6%, P = 0.0016) and superomedial (8.7 vs 4.8%, P = 0.016) hip joint. Of the 71 symptomatic hips, 22 (31%) hips demonstrated either anterior and/or posterior grade 2/3 OA on CT, and 9 (9/22, 41%) of these hips had superior or superomedial grade 0/1 OA. CONCLUSION: CT may be warranted when the patient has pain suggestive of osteoarthritis not detected on radiographs.

Bilateral simultaneous hip and knee replacement: an epidemiological nationwide study from 2001 to 2016.

BACKGROUND: Several studies have compared the pros and cons of simultaneous bilateral versus staged bilateral hip and knee replacement but the outcomes of these two surgical options remains a matter of controversy. This study aimed to evaluate demographic features, incidence and hospitalization rates of bilateral one stage total hip and knee arthroplasty in Italy. METHODS: The Italian Ministry of Health's National Hospital Discharge Reports (SDO) were used to gather data. This study referred to the adult population (+ 20 years of age) from 2001 to 2015 for hip arthroplasty and from 2001 to 2016 for knee arthroplasty. RESULTS: Overall, 1,544 bilateral simultaneous hip replacement were carried out. The incidence rate was 0.21 cases per 100,000 adult Italian residents. Male/female ratio was 1.1. The average days of hospital stay was 11.7 ± 11.8 days. The main primary codified diagnosis was: osteoarthrosis, localized, primary, pelvic region and thigh (ICD code: 715.15). 2,851 bilateral simultaneous knee replacement were carried out. The incidence rate was 0.37 cases per 100,000 adult Italian residents. Male/female ratio was 0.6. The average days of hospital stay was 7.7 ± 5.8 days. The main primary codified diagnosis was: osteoarthrosis, localized, primary, lower leg (ICD code: 715.16). CONCLUSIONS: The burden of hip and knee osteoarthrosis as a leading cause of bilateral joint replacement is significant in Italy. The national registers' longitudinal analysis may provide data for establishing international guidelines regarding the appropriate indications for one stage bilateral simultaneous hip or knee replacement versus two stage.

Fall risk in patient with dysplastic hip osteoarthritis.

PURPOSE: Patients with dysplastic hip osteo arthritis (DHOA) often have a spinopelvic imbalance, and they are more likely to experience falls. This study aimed to evaluate the risk factors for falls in patients with DHOA, including spinopelvic parameters. METHODS: In this cross-sectional study, a total of 103 patients with DHOA were included from 2019 to 2021. Fall risk was evaluated using the Fall Risk Index 5 items version (FRI-5). Demographics, functional outcomes, and spinopelvic parameters were compared between the high-risk group (FRI-5 ≥ 6) and the low-risk group (FRI-5 < 6). Multivariate analysis was performed using factors with significant differences in univariate analysis. RESULTS: High-risk and low-risk groups comprised 54 and 49 patients, respectively. Females were significantly more common in the high-risk group than in the low-risk group. The Harris Hip Score was significantly lower in the high-risk group than in the low-risk group (p = 0.02). Pelvic incidence, tilt, and obliquity were significantly higher in the high-risk group than in the low-risk group (p < 0.01). In multivariate analysis, female sex (odds ratio [OR]: 3.76, 95% confidence interval [CI]: 1.11-12.64, p = 0.03), pelvic obliquity (OR: 1.36, 95% CI: 1.09-1.71, p < 0.01), and Harris hip score (OR: 0.96, 95% CI: 0.93-0.99, p = 0.02) were identified as risk factors. CONCLUSION: Female sex, pelvic obliquity, and low Harris hip score were associated with an increased risk of falls among patients with DHOA.

Total hip arthroplasty for adult patients with hip arthritis in Jordan: clinical profiles and patient characteristics.

PURPOSE: Total Hip Arthroplasty (THA) is one of the most commonly performed orthopaedic surgeries, with hip arthritis being the main indication. This procedure is usually performed when other non-surgical methods fail to relieve patients' hip pain and improve their quality of life. However, limited information exists to identify and compare the demographics and clinical characteristics of patients undergoing this procedure in Jordan. This study aims to identify these demographic and clinical characteristics and compare the findings in terms of gender differences. METHODOLOGY: This is a retrospective study that analysed the hospital records of 650 patients undergoing THA in tertiary referral hospital in Jordan over a four-year period from January 2019 to December 2022. The collected data were classified into three categories: demographic characteristics, perioperative variables, and patients' related health profiles. IBM's Statistical Package for the Social Sciences (SPSS) version 23 software (IBM, USA) and descriptive analysis were used for data analysis. RESULTS: Two-thirds of the sample studied were female (63.4%). In terms of bleeding profiles, the mean intraoperative blood loss was 542 millilitres. The major indication for THA was degenerative hip arthritis (50.5%), followed by hip dysplasia (40.3%).. Comparing the findings of the two gender groups, females were more likely to have degenerative and dysplastic hip arthritis (221 and 157, p = 0.04 and p = 0.1, respectively) when compared to males. Although males were more likely to lose more blood during the surgery (557 ml vs. 533 ml, p = 0.33, females needed more blood transfusions both during (21 vs. 6 patients, p = 0.12) and after the surgery (57 vs. 16 patients, p = 0.006). Furthermore, females were more likely to have comorbidities such hypertension (293 vs. 179 patients, p = 0.20), and hypothyroidism (313 vs 187, p = 0.36), and diabetes (85 vs. 38 patients, p = 0.15), among many other health conditions. However, in the study sample, male smokers outnumbered female smokers (132 vs. 63). CONCLUSION: Gender highly impacted the immediate surgical outcomes of patients who underwent THA. Females were more likely to need blood transfusions both during and after the surgery and had lower post-operative haemoglobin readings. In addition, females had more comorbidities and degenerative hip osteoarthritis. We believe that raising awareness about comorbidity management, preoperative smoking cessation, and perioperative blood transfusion management can improve medical and surgical outcomes.

The prevalence of bilateral and ipsilateral radiographic osteoarthritis is high in White, Asian and Native Hawaiian/Pacific Islanders presenting for unilateral knee or hip arthroplasty.

BACKGROUND: It is estimated that one-third of patients presenting with unilateral joint pain have contralateral osteoarthritis (OA) at first presentation. Most studies have primarily examined White patient cohorts. The purpose of this study was to determine the prevalence of contralateral joint OA for patients presenting for unilateral total knee (TKA), unicompartmental knee (UKA) or total hip arthroplasty (THA) among Asian, Native Hawaiian/Pacific Islander and White patients. METHODS: Bilateral radiographic reports at initial presentation of 2,312 subjects who underwent unilateral arthroplasties (332 UKAs, 933 TKAs and 1,047 THAs) were reviewed. The presence of contralateral OA was recorded and compared by racial group and type of arthroplasty performed. Parametric statistical analyses were performed to determine differences between groups. Multivariable analyses were completed for each arthroplasty group to determine the influence on the presence of contralateral OA, presented as odds ratios and 95% confidence intervals. RESULTS: Contralateral joint OA was present in 86.7%, 90.4% and 70.4% of UKA, TKA and THA patients, respectively. Concurrent hip OA was present in 41.6% and 59.5% of UKA and TKA patients. No racial differences in the prevalence of contralateral knee OA were found for knee arthroplasty patients. White patients (74.6%) had a greater prevalence of contralateral hip OA compared to Asians (66.5%, p = 0.037) amongst THA recipients. Increased age and body mass index were significantly associated with the presence of contralateral knee OA. Increased age, being male and being White were significant contributors for the presence of contralateral hip OA. CONCLUSION: The prevalence of contralateral joint OA and concurrent hip OA is high in all three racial groups. Due to the extensive prevalence of contralateral and concurrent knee and hip OA, bilateral radiographic evaluation should be considered for all patients presenting with unilateral hip or knee pain due to OA.

Do sex, age, and comorbidities modify the association of socioeconomic status and opioid use after total hip arthroplasty?: a population-based study from the Danish Hip Arthroplasty Register.

BACKGROUND AND PURPOSE: We aimed to examine the association between socioeconomic status (SES) markers and opioid use after primary total hip arthroplasty (THA) due to osteoarthritis, and whether sex, age, or comorbidities modify any association. METHODS: Using Danish databases, we included 80,038 patients undergoing primary THA (2001-2018). We calculated prevalences and prevalence ratios (PRs with 95% confidence intervals [CIs]) of immediate post-THA opioid use (≥ 1 prescription within 1 month) and continued opioid use (≥ 1 prescription in 1-12 months) among immediate opioid users. Exposures were individual-based education, cohabitation, and wealth. RESULTS: The prevalence of immediate opioid use was ~45% in preoperative non-users and ~60% in preoperative users (≥ 1 opioid 0-6 months before THA). Among non-users, the prevalences and PRs of continued opioid use were: 28% for low vs. 21% for high education (PR 1.28, CI 1.20-1.37), 27% for living alone vs. 23% for cohabiting (PR 1.09, CI 1.04-1.15), and 30% for low vs. 20% for high wealth (PR 1.43, CI 1.35-1.51). Among users, prevalences were 67% for low vs. 55% for high education (1.22, CI 1.17-1.27), 68% for living alone vs. 60% for cohabiting (PR 1.10, CI 1.07-1.12), and 73% for low wealth vs. 54% for high wealth (PR 1.32, CI 1.28-1.36). Based on testing for interaction, sex, age, and comorbidity did not statistically significant modify the associations. Nevertheless, associations were stronger in younger patients for all SES markers (mainly for non-users). CONCLUSION: Markers of low SES were associated with a higher prevalence of continued post-THA opioid use. Age modified the magnitude of the associations, but it was not statistically significant.

Occurrence of comorbidity following osteoarthritis diagnosis: a cohort study in the Netherlands.

OBJECTIVE: To determine the risk of comorbidity following diagnosis of knee or hip osteoarthritis (OA). DESIGN: A cohort study was conducted using the Integrated Primary Care Information database, containing electronic health records of 2.5 million patients from the Netherlands. Adults at risk for OA were included. Diagnosis of knee or hip OA (=exposure) and 58 long-term comorbidities (=outcome) were defined by diagnostic codes following the International Classification of Primary Care coding system. Time between the start of follow-up and incident diagnosis of OA was defined as unexposed, and between diagnosis of OA and the end of follow-up as exposed. Age and sex adjusted hazard ratios (HRs) comparing comorbidity rates in exposed and unexposed patient time were estimated with 99.9% confidence intervals (CI). RESULTS: The study population consisted of 1,890,712 patients. For 30 of the 58 studied comorbidities, exposure to knee OA showed a HR larger than 1. Largest positive associations (HR with (99.9% CIs)) were found for obesity 2.55 (2.29-2.84) and fibromyalgia 2.06 (1.53-2.77). For two conditions a HR < 1 was found, other comorbidities showed no association with exposure to knee OA. For 26 comorbidities, exposure to hip OA showed a HR larger than 1. The largest were found for polymyalgia rheumatica 1.81 (1.41-2.32) and fibromyalgia 1.70 (1.10-2.63). All other comorbidities showed no associations with hip OA. CONCLUSION: This study showed that many comorbidities were diagnosed more often in patients with knee or hip OA. This suggests that the management of OA should consider the risk of other long-term-conditions.

Bariatric surgery, osteoarthritis and arthroplasty of the hip and knee in Swedish Obese Subjects - up to 31 years follow-up of a controlled intervention study.

OBJECTIVE: To study the long-term effect of obesity and bariatric surgery on incidences of osteoarthritis and arthroplasty of hip and knee. DESIGN: Hazard ratios (HR) and incidence rates (IR) of osteoarthritis and arthroplasty of hip and knee were studied in the prospective, controlled, non-randomized Swedish Obese Subjects (SOS) study (bariatric surgery group, n = 2007; matched controls given usual obesity care, n = 2040) and the SOS reference cohort (n = 1135, general population). Osteoarthritis diagnosis and arthroplasty for osteoarthritis were captured from the National Swedish Patient Register. Median follow-up time was 21.2 (IQR 16.4-24.8), 22.9 (IQR 19.1-25.7), and 20.1 years (IQR 18.7-20.9) for the control group, surgery group and reference cohort, respectively. RESULTS: The surgery group displayed lower incidence of hip osteoarthritis (IR 5.3, 95% CI 4.7-6.1) compared to controls (IR 6.6, 95% CI 5.9-7.5, adjHR 0.83, 95% CI 0.69-1.00) but similar incidence of hip arthroplasty. Similar incidence of knee osteoarthritis was observed in the surgery group and controls, but knee arthroplasty was more common in the surgery group (IR 7.4, 95% CI 6.6-8.2 and 5.6, 95% CI 4.9-6.4, adjHR 1.45, 95% CI 1.22-1.74). The reference cohort displayed lower incidences of osteoarthritis and arthroplasty of hip and knee compared with the surgery group and controls. CONCLUSION: Bariatric surgery did not normalize the increased risk of knee and hip osteoarthritis in patients with obesity but was associated with an increased incidence of knee arthroplasty compared to the control group. With the limitations inherent to the present data, additional studies are needed to confirm these results. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01479452.

Changes to consultations and diagnosis of osteoarthritis in primary care during the COVID-19 pandemic.

OBJECTIVE: General practitioners (GP) are often the first medical professionals to treat musculoskeletal complaints. Yet the impact of COVID-19 on primary care utilisation for musculoskeletal complaints is largely unknown. This study quantifies the impact of the pandemic on primary care utilisation for musculoskeletal complaints and specifically osteoarthritis (OA) in the Netherlands. DESIGN: We extracted data on GP consultations in 2015-2020 from 118,756 patients over 45 years of age and estimated reductions in consultations in 2020 as compared to 5-year average. Outcomes were GP consultations for: any musculoskeletal complaints, knee and hip OA, knee and hip complaints, and newly diagnosed knee and hip OA/complaints. RESULTS: The relative reductions in consultations ranged from 46.7% (95% confidence intervals (CI): 43.9-49.3%) (all musculoskeletal consultations) to 61.6% (95% CI: 44.7-73.3%) (hip complaints) at the peak of the first wave, and from 9.3% (95% CI: 5.7-12.7%) (all musculoskeletal consultations) to 26.6% (95% CI: 11.5-39.1%) (knee OA) at the peak of the second wave. The reductions for new diagnoses were 87.0% (95% CI: 71.5-94.1%) for knee OA/complaints, and 70.5% (95% CI: 37.7-86.0%) for hip OA/complaints at the peak of the first wave, and not statistically significant at the peak of the second wave. CONCLUSION: We observed 47% reduction in GP consultations for musculoskeletal disorders during the first wave and 9% during the second wave. For hip and knee OA/complaints, the reductions were over 50% during the first, and 10% during the second wave. This disruption may lead to accumulation of patients with severe OA symptoms and more requests for arthroplasty surgery.

Classification of patients with osteoarthritis through clusters of comorbidities using 633 330 individuals from Spain.

OBJECTIVES: To explore clustering of comorbidities among patients with a new diagnosis of OA and estimate the 10-year mortality risk for each identified cluster. METHODS: This is a population-based cohort study of individuals with first incident diagnosis of OA of the hip, knee, ankle/foot, wrist/hand or 'unspecified' site between 2006 and 2020, using SIDIAP (a primary care database representative of Catalonia, Spain). At the time of OA diagnosis, conditions associated with OA in the literature that were found in ≥1% of the individuals (n = 35) were fitted into two cluster algorithms, k-means and latent class analysis. Models were assessed using a range of internal and external evaluation procedures. Mortality risk of the obtained clusters was assessed by survival analysis using Cox proportional hazards. RESULTS: We identified 633 330 patients with a diagnosis of OA. Our proposed best solution used latent class analysis to identify four clusters: 'low-morbidity' (relatively low number of comorbidities), 'back/neck pain plus mental health', 'metabolic syndrome' and 'multimorbidity' (higher prevalence of all studied comorbidities). Compared with the 'low-morbidity' cluster, the 'multimorbidity' cluster had the highest risk of 10-year mortality (adjusted hazard ratio [HR]: 2.19 [95% CI: 2.15, 2.23]), followed by the 'metabolic syndrome' cluster (adjusted HR: 1.24 [95% CI: 1.22, 1.27]) and the 'back/neck pain plus mental health' cluster (adjusted HR: 1.12 [95% CI: 1.09, 1.15]). CONCLUSION: Patients with a new diagnosis of OA can be clustered into groups based on their comorbidity profile, with significant differences in 10-year mortality risk. Further research is required to understand the interplay between OA and particular comorbidity groups, and the clinical significance of such results.

Trajectories of physical function and quality of life in people with osteoarthritis: results from a 10-year population-based cohort.

OBJECTIVE: To identify long-term trajectories of physical function and health-related quality of life (HRQoL) among people with hip and/or knee osteoarthritis (HKOA) and the sociodemographic, lifestyle, and clinical factors associated with different trajectories. METHODS: Participants with HKOA from the EpiDoC study, a 10-year follow-up (2011-2021) population-based cohort, were considered. Sociodemographic, lifestyle, and clinical variables were collected at baseline in a structured interview and clinical appointment. Physical function and HRQoL were evaluated with the Health Assessment Questionnaire (HAQ) and EuroQoL, respectively, at baseline and the three follow-ups. Group-based trajectory modeling identified physical function and HRQoL trajectories. Multinomial logistic regression analyzed the associations between the covariates of interest and trajectory assignment (p < 0.05). RESULTS: We included 983 participants with HKOA. We identified three trajectories for each outcome: "consistently low disability" (32.0%), "slightly worsening moderate disability" (47.0%), and "consistently high disability" (21.0%) for physical function; "consistently high HRQoL" (18.3%), "consistently moderate HRQoL" (48.4%) and "consistently low HRQoL" (33.4%) for HRQoL. Age ≥ 75 years, female sex, multimorbidity, and high baseline clinical severity were associated with higher risk of assignment to poorer physical function and HRQoL trajectories. Participants with high education level and with regular physical activity had a lower risk of assignment to a poor trajectory. Unmanageable pain levels increased the risk of assignment to the "consistently moderate HRQoL" trajectory. CONCLUSION: Although the trajectories of physical function and HRQoL remained stable over 10 years, approximately 70% of people with HKOA maintained moderate or low physical function and HRQoL over this period. Modifiable risk factors like physical activity, multimorbidity and clinical severity were associated with poorer physical function and HRQoL trajectories. These risk factors may be considered in tailored healthcare interventions.

Does lower educational attainment increase the risk of osteoarthritis surgery? a Swedish twin study.

BACKGROUND: Previous studies have reported an inverse association between educational attainment and different osteoarthritis (OA) outcomes. However, none of the previous studies have accounted for potential confounding by early-life environment and genetics. Thus, we aimed to examine the association between educational attainment and knee and hip OA surgery using twin data. METHODS: From the Swedish Twin Registry (STR), we identified dizygotic (DZ) and monozygotic (MZ) twins. All twins in the STR aged 35 to 64 years were followed from January the 1st 1987 or the date they turned 35 years until OA surgery, relocation outside Sweden, death or the end of 2016 (18,784 DZ and 8,657 MZ complete twin pairs). Associations between educational attainment and knee and hip OA surgery were estimated in models matched on twin pairs, using Weibull within-between (WB) shared frailty model. RESULTS: For knee OA surgery, the analysis matched on MZ twins yielded a within-estimate hazard ratio (HR) per 3 years of education, of 1.06 (95% CI: 0.81, 1.32), suggesting no association between the outcome and the individual´s education. Rather, there seemed to be a so called familial effect of education, with a between-pair estimate of HR = 0.71 (95% CI: 0.41, 1.01). For hip OA surgery, the within- and between-pair estimates for MZ twins were 0.92 (95% CI: 0.69, 1.14) and 1.15 (95% CI: 0.87, 1.42), respectively. CONCLUSIONS: Our results suggest that the inverse associations between education and knee/hip OA surgery observed in cohort studies are potentially confounded by unobserved familial factors like genetics and/or early life exposures.