Mortality in patients with incident rheumatoid arthritis and depression: a Danish cohort study of 11 071 patients and 55 355 comparators.

OBJECTIVES: In patients with RA, the association between mortality and depression has been investigated only in patients with prevalent RA. In this study, we estimated the mortality risk associated with depression, defined as the first filling of a prescription for antidepressants, in patients with incident RA and background population comparators. METHODS: From 2008 to 2018, we identified patients with incident RA in the nationwide Danish rheumatologic database, DANBIO. For each patient, we randomly selected five comparators. Participants were not treated with antidepressants or diagnosed with depression 3 years prior to the index date. From other registers we collected data on socioeconomic status, mortality and cause of death using unique personal identifiers. Using Cox models, we calculated hazard rate ratios (HRR) with 95% CI. RESULTS: In depressed patients with RA vs patients without depression, adjusted HRR for all-cause mortality was 5.34 (95% CI 3.02, 9.45) during 0-2 years and 3.15 (95% CI 2.62, 3.79) during the total follow-up period, and highest in patients <55 years with HRR 8.13 (95% CI 3.89, 17.02). In comparators with depression vs comparators without depression, the association with mortality was similar to that in patients with RA. There were no unnatural causes of death among depressed patients with RA. The most frequent natural causes of death were cancer, cardiovascular disease, stroke and pneumonia. CONCLUSION: In patients with RA, depression was a predictor of death but with a strength similar to that in matched comparators.

Any infection among patients with hip fracture: Predictive ability of Charlson, Elixhauser, Rx-Risk, and Nordic comorbidity indices.

BACKGROUND: In studies on infection after hip fracture surgery, a common and serious complication, it remains unknown which comorbidity index is best for case-mix confounder adjustment. We evaluated the predictive ability of Charlson Comorbidity Index (CCI), Elixhauser Comorbidity Index (ECI), Rx-Risk Index (Rx-Risk), and Nordic Multimorbidity Index (NMI) for any infection up to 1 year from discharge after hip fracture surgery. METHODS: Using Danish medical registries, we included 92,600 patients (mean age 83 years) surgically treated for hip fracture between 2004 and 2018. Comorbidity-index scores were calculated using prevalence of diagnosis codes, prescription codes, or both. Lookback periods of 1, 5, and 10 years were applied. Logistic regression was used to calculate c-index to assess discrimination of comorbidity indices individually and in combination with a base model of age and sex. Outcome was any infection (not only surgical site infection) in-hospital and 1 year after discharge. RESULTS: At 10-year lookback period, the c-index for individual comorbidity indices for in-hospital infections varied from 0.53 to 0.56, similar to base model alone (0.56). The predictive ability of comorbidity indices in combination with base model varied from 0.56 to 0.57. Within 1 year after discharge, NMI in combination with base model had best predictive ability for infection (c-index = 0.62), followed by CCI and ECI (c-index = 0.60) and Rx-Risk (c-index = 0.58). Discrimination was similar for all lookback periods. CONCLUSIONS: Comorbidity indices have low predictive ability for any infection up to 1 year after hip fracture surgery, similar to that of age and sex alone. For case-mix adjustment, evaluated comorbidity indices are of equal value.

Enhancing the data capture of periprosthetic joint infections in the Danish Knee Arthroplasty Registry: validity assessment and incidence estimation.

BACKGROUND AND PURPOSE: Revisions due to periprosthetic joint infection (PJI) are underestimated in national arthroplasty registries. Our primary objective was to assess the validity in the Danish Knee Arthroplasty Register (DKR) of revisions performed due to PJI against the Healthcare-Associated Infections Database (HAIBA). The secondary aim was to describe the cumulative incidences of revision due to PJI within 1 year of primary total knee arthroplasty (TKA) according to the DKR, HAIBA, and DKR/HAIBA combined. METHODS: This longitudinal observational cohort study included 56,305 primary TKAs (2010-2018), reported in both the DKR and HAIBA. In the DKR, revision performed due to PJI was based on pre- and intraoperative assessment disclosed by the surgeon immediately after surgery. In HAIBA, PJI was identified from knee-related revision procedures coinciding with 2 biopsies with identical microbiological pathogens. We calculated the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of revision due to PJI in the DKR (vs. HAIBA, within 1 year of TKA) with 95% confidence intervals (CI). Cumulative incidences were calculated using the Kaplan-Meier method. RESULTS: The DKR's sensitivity for PJI revision was 58% (CI 53-62) and varied by TKA year (41%-68%) and prosthetic type (31% for monoblock; 63% for modular). The specificity was 99.8% (CI 99.7-99.8), PPV 64% (CI 62-72), and NPV 99.6% (CI 99.6-99.7). 80% of PJI cases not captured by the DKR were caused by non-reporting rather than misclassification. 33% of PJI cases in the DKR or HAIBA were culture-negative. Considering potential misclassifications, the best-case sensitivity was 64%. The cumulative incidences of PJI were 0.8% in the DKR, 0.9% in HAIBA, and 1.1% when combining data. CONCLUSION: The sensitivity of revision due to PJI in the DKR was 58%. The cumulative incidence of PJI within 1 year after TKA was highest (1.1%) when combining the DKR and HAIBA, showing that incorporating microbiology data into arthroplasty registries can enhance PJI validity.

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.

Multimorbidity measured with Charlson Comorbidity Index is not associated with clinically relevant risk of revision after primary total hip arthroplasty: a population-based cohort study on 98,647 patients from the Danish Hip Arthroplasty Register.

BACKGROUND AND PURPOSE: Evidence for guiding healthcare professionals on the risks of total hip arthroplasty (THA) in multimorbid patients is sparse. We aimed to examine the association between multimorbidity and the risk of revision due to any cause and specific causes after primary THA due to osteoarthritis. PATIENTS AND METHODS: We identified 98,647 THA patients and subsequent revisions in the Danish Hip Arthroplasty Register from 1995 to 2018. Multimorbidity was measured with the Charlson Comorbidity Index (CCI). Using the CCI (low, medium, high), we calculated the cumulative incidence function (CIF) of first revision up to 10 years after THA. Adjusted cause-specific hazard ratios (aHRs) were estimated using Cox regressions. All estimates are presented with 95% confidence intervals (CI). RESULTS: Overall, the prevalence of patients with low, medium, and high CCI was 70%, 24%, and 6%. The CIF of any revision within 10 years was 6.5% (CI 6.2-6.7) in low and 6.5% (CI 5.8-7.3) in high CCI, with an aHR of 1.4 (CI 1.2-1.6) for patients with high compared with low CCI. The corresponding aHRs for cause-specific revision were 1.3 (CI 1.0-1.6) for aseptic loosening within 10 years, 1.2 (CI 0.9-1.6) for infection, and 1.7 (CI 1.3-2.2) for dislocation, both within 2 years. CONCLUSION: Multimorbidity is associated with a minor but not clinically relevant increased risk of revision up to 10 years after primary THA.

Sex and age differences in the use of analgesic drugs before and after primary total hip arthroplasty in 105,520 Danish patients.

BACKGROUND: We examined analgesic drug use before and after total hip arthroplasty (THA) by sex and age, and impact of comorbidity in that context. METHODS: Using Danish nationwide medical registries, we included 105,520 THA patients (1996-2018). We calculated prevalence of overall analgesic drug use and use of NSAIDs and opioids separately in four quarters before (-Q4 to -Q1) and after THA (Q1 to Q4). -Q4 and Q4 was compared using prevalence rate ratios (PRR) with 95% confidence interval (CI). RESULTS: Among women, analgesic drug use was 46% in -Q4, 65% in Q1, but decreased to 31% in Q4 (PRR: 0.68 (CI: 0.67-0.69)). Among men, these numbers were 39% in -Q4, 62% in Q1, and 23% in Q4 (PRR: 0.61 (CI: 0.60-0.63)). Analgesic drug use was higher among older patients in all quarters except Q1. Analgesic drug use decreased from 40% in -Q4 to 25% in Q4 (PRR: 0.62 (CI: 0.59-0.64)) in patients <55 years, and from 44% to 30% in patients >85 years, (PRR: 0.67 (CI: 0.63-0.71)). Women used more NSAIDs and opioids than men. Older patients used more opioids compared to younger, while variation in NSAID use by age was small. Decrease in analgesic drug use from -Q4 to Q4 was least pronounced in patients with comorbidity history. CONCLUSIONS: Women and older patients have higher prevalence of analgesic drug use before and after THA, and a smallest reduction in analgesic drug use from before to after THA. Comorbidity history modified these associations.

Temporal trends in revision rate due to knee periprosthetic joint infection: a study of 115,120 cases from the Danish Knee Arthroplasty Register.

BACKGROUND AND PURPOSE: We aimed to examine the temporal trends in periprosthetic joint infection (PJI) revision incidence after knee arthroplasty (KA) from 1997 through 2019. PATIENTS AND METHODS: 115,120 primary KA cases from the Danish Knee Arthroplasty Register were followed until the first PJI revision. We computed cumulative incidences and adjusted hazard ratios (aHRs) of PJI revision by calendar periods and several patient- and surgical-related risk factors. Results were analyzed from 0-3 months and from 3-12 months after KA. RESULTS: The overall 1-year PJI revision incidence was 0.7%, increasing from 0.5% to 0.7% (1997 through 2019). The incidence of PJI revision within 3 months increased from 0.1% to 0.5% (1997 through 2019). The adjusted hazard ratio (aHR) within 1 year of primary KA was 5.1 comparing 2017-2019 with 2001-2004. The PJI revision incidence from 3-12 months of KA decreased from 0.4% to 0.2%, with an aHR of 0.5 for 2017-2019 vs. 2001-2004. Male sex, age 75-84 (vs. 65-74), and extreme obesity (vs. normal weight) were positively associated with the risk of PJI revision within 3 months, whereas only male sex was associated from 3-12 months. Partial knee arthroplasty (PKA) vs. total KA was associated with a lower risk of PJI revision both within 3 months and 3-12 months of KA. CONCLUSION: We observed an increase in PJI revision within 3 months of KA, and a decrease in PJI revision incidence from 3-12 months from 1997 through 2019. The reasons for this observed time-trend are thought to be multifactorial. PKA was associated with a lower risk of PJI revision.

Increasing risk of revision due to infection after primary total hip arthroplasty: results from the Nordic Arthroplasty Register Association.

BACKGROUND AND PURPOSE: The incidence of periprosthetic joint infection after total hip arthroplasty (THA) may be increasing. We performed time-trend analyses of risk, rates, and timing of revision due to infection after primary THAs in the Nordic countries from the period 2004-2018. PATIENTS AND METHODS: 569,463 primary THAs reported to the Nordic Arthroplasty Register Association from 2004 to 2018 were studied. Absolute risk estimates were calculated by Kaplan-Meier and cumulative incidence function methods, whereas adjusted hazard ratios (aHR) were assessed by Cox regression with the first revision due to infection after primary THA as primary endpoint. In addition, we explored changes in the time span from primary THA to revision due to infection. RESULTS: 5,653 (1.0%) primary THAs were revised due to infection during a median follow-up time of 5.4 (IQR 2.5-8.9) years after surgery. Compared with the period 2004-2008, the aHRs for revision were 1.4 (95% confidence interval [CI] 1.3-1.5) for 2009-2013, and 1.9 (CI 1.7-2.0) for 2014-2018. The absolute 5-year rates of revision due to infection were 0.7% (CI 0.7-0.7), 1.0% (CI 0.9-1.0), and 1.2% (CI 1.2-1.3) for the 3 time periods respectively. We found changes in the time span from primary THA to revision due to infection. Compared with 2004-2008, the aHR for revision within 30 days after THA was 2.5 (CI 2.1-2.9) for 2009-2013, and 3.4 (CI 3.0-3.9) for 2013-2018. The aHR for revision within 31-90 days after THA was 1.5 (CI 1.3-1.9) for 2009-2013, and 2.5 (CI 2.1-3.0) for 2013-2018, compared with 2004-2008. CONCLUSION: The risk of revision due to infection after primary THA almost doubled, both in absolute cumulative incidence and in relative risk, throughout the period 2004-2018. This increase was mainly due to an increased risk of revision within 90 days of THA. This may reflect a "true" increase (i.e., frailer patients or more use of uncemented implants) and/or an "apparent" increase (i.e., improved diagnostics, changed revision strategy, or completeness of reporting) in incidence of periprosthetic joint infection. It is not possible to disclose such changes in the present study, and this warrants further research.

Does choice of bearings influence the survival of cementless total hip arthroplasty in patients aged 20-55 years? Comparison of 21,594 patients reported to the Nordic Arthroplasty Register Association dataset 2005-2017.

BACKGROUND AND PURPOSE: The bearings with the best survivorship for young patients with total hip arthroplasty (THA) should be identified. We compared hazard ratios (HR) of revision of primary stemmed cementless THAs with metal-on-metal (MoM), ceramic-on-ceramic (CoC), and ceramic-on-highly-crosslinked-polyethylene (CoXLP) with that of metal-on-highly-crosslinked-polyethylene (MoXLP) bearings in patients aged 20-55 years with primary osteoarthritis or childhood hip disorders. PATIENTS AND METHODS: From the Nordic Arthroplasty Register Association dataset we included 1,813 MoM, 3,615 CoC, 5,947 CoXLP, and 10,219 MoXLP THA in patients operated on between 2005 and 2017 in a prospective cohort study. We used the Kaplan-Meier estimator for THA survivorship and Cox regression to estimate HR of revision adjusted for confounders (including 95% confidence intervals [CI]). MoXLP was used as reference. HRs were calculated during 3 intervals (0-2, 2-7, and 7-13 years) to meet the assumption of proportional hazards. RESULTS: Median follow-up was 5 years for MoXLP, 10 years for MoM, 6 years for CoC, and 4 years for CoXLP. 13-year Kaplan-Meier survival estimates were 95% (CI 94-95) for MoXLP, 82% (CI 80-84) for MoM, 93% (CI 92-95) for CoC, and 93% (CI 92-94) for CoXLP bearings. MoM had higher 2-7 and 7-13 years' adjusted HRs of revision (3.6, CI 2.3-5.7 and 4.1, CI 1.7-10). MoXLP, CoC, and CoXLP had similar HRs in all 3 periods. The 7-13-year adjusted HRs of revision of CoC and CoXLP were statistically non-significantly higher. CONCLUSION: In young patients, MoXLP for primary cementless THA had higher revision-free survival and lower HR for revision than MoM bearings. Longer follow-up is needed to compare MoXLP, CoC, and CoXLP.

The use of antibiotic-loaded bone cement and systemic antibiotic prophylactic use in 2,971,357 primary total knee arthroplasties from 2010 to 2020: an international register-based observational study among countries in Africa, Europe, North America, and Oceania.

BACKGROUND AND PURPOSE: Antibiotic-loaded bone cement (ALBC) and systemic antibiotic prophylaxis (SAP) have been used to reduce periprosthetic joint infection (PJI) rates. We investigated the use of ALBC and SAP in primary total knee arthroplasty (TKA). PATIENTS AND METHODS: This observational study is based on 2,971,357 primary TKAs reported in 2010-2020 to national/regional joint arthroplasty registries in Australia, Denmark, Finland, Germany, Italy, the Netherlands, New Zealand, Norway, Romania, South Africa, Sweden, Switzerland, the UK, and the USA. Aggregate-level data on trends and types of bone cement, antibiotic agents, and doses and duration of SAP used was extracted from participating registries. RESULTS: ALBC was used in 77% of the TKAs with variation ranging from 100% in Norway to 31% in the USA. Palacos R+G was the most common (62%) ALBC type used. The primary antibiotic used in ALBC was gentamicin (94%). Use of ALBC in combination with SAP was common practice (77%). Cefazolin was the most common (32%) SAP agent. The doses and duration of SAP used varied from one single preoperative dosage as standard practice in Bolzano, Italy (98%) to 1-day 4 doses in Norway (83% of the 40,709 TKAs reported to the Norwegian arthroplasty register). CONCLUSION: The proportion of ALBC usage in primary TKA varies internationally, with gentamicin being the most common antibiotic. ALBC in combination with SAP was common practice, with cefazolin the most common SAP agent. The type of ALBC and type, dose, and duration of SAP varied among participating countries.

Development and validation of a model for predicting mortality in patients with hip fracture.

OBJECTIVE: to develop a user-friendly prediction tool of 1-year mortality for patients with hip fracture, in order to guide clinicians and patients on appropriate targeted preventive measures. DESIGN: population-based cohort study from 2011 to 2017 using nationwide data from the Danish Hip Fracture Registry. SUBJECTS: a total of 28,791 patients age 65 and above undergoing surgery for a first-time hip fracture. METHODS: patient-related prognostic factors at the time of admission were assessed as potential predictors: Nursing home residency, comorbidity (Charlson Comorbidity Index [CCI] Score), frailty (Hospital Frailty Risk Score), basic mobility (Cumulated Ambulation Score), atrial fibrillation, fracture type, body mass index (BMI), age and sex. Association with 1-year mortality examined by determining the cumulative incidence, applying univariable logistic regression and assessing discrimination (area under the receiver operating characteristics curve [AUROC]). The final model (logistic regression) was utilised on a development cohort (70% of patients). Discrimination and calibration were assessed on the validation cohort (remaining 30% of patients). RESULTS: all predictors showed an association with 1-year mortality, but discrimination was moderate. The final model included nursing home residency, CCI Score, Cumulated Ambulation Score, BMI and age. It had an acceptable discrimination (AUROC 0.74) and calibration, and predicted 1-year mortality risk spanning from 5 to 91% depending on the combination of predictors in the individual patient. CONCLUSIONS: using information obtainable at the time of admission, 1-year mortality among patients with hip fracture can be predicted. We present a user-friendly chart for daily clinical practice and provide new insight regarding the interplay between prognostic factors.

Corrigendum: Risk of reoperation due to surgical site infection in 74,771 hip fracture patients: a Danish nationwide cohort study.

Corrigendum of Acta Orthop 2022; 93: 760-766. doi: https://doi.org/10.2340/17453674.2022.4580.

Risk of reoperation due to surgical site infection in 74,771 hip fracture patients: a Danish nationwide cohort study.

BACKGROUND AND PURPOSE: Surgical site infection (SSI) after hip fracture surgery is a feared condition. We examined the trend in incidence of reoperation due to SSI up to 1 year following hip fracture surgery from 2005 to 2016 and risk factors of SSI by age, sex, comorbidity, type of fracture, and surgery. PATIENTS AND METHODS: We conducted a population-based, nationwide cohort study using data from the Danish Multidisciplinary Hip Fracture Register (DMHFR). We included 74,771 patients aged 65 and up who underwent surgery from 2005 to 2016 for all types of hip fracture. We calculated net risk of reoperation using Kaplan­Meier method, and, with Cox regression, adjusted hazard ratios (HRs) with a 95% confidence interval (CI) for reoperation due to SSI. RESULTS: Overall, the 1-year net risk of reoperation due to SSI was 1.6%. The HR was higher for patients undergoing total/hemiarthroplasty surgery versus internal fixation (HR = 1.5; 95%CI 1.3­1.8) and lower for patients with per-/subtrochanteric fracture versus femoral neck fracture (HR = 0.6; CI 0.6­0.7). The risk of reoperation due to SSI decreased over time; HR was 0.7 (CI 0.5­0.8) for 2015­2016 compared with 2005­2006. Risk of reoperation decreased with increasing age; the HR was 0.8 (CI 0.7­1.0) in the more than 85-year-olds compared with 65­74-year-old patients. Charlson Comorbidity Index of ≥ 3 was associated with a higher risk of reoperation due to SSI, HR was 1.3 (CI 1.1­1.6). INTERPRETATION: The net risk of reoperations due to SSI in our study was lower than previously assumed. We identified several risk factors for increased risk of reoperation due to SSI, most noticeably treatment with arthroplasty vs. internal fixation, as well as younger age, high comorbidity burden, and femoral neck fracture diagnosis.

Socioeconomic status and use of analgesic drugs before and after primary hip arthroplasty: a population-based cohort study of 103,209 patients during 1996-2018.

Background and purpose - Total hip arthroplasty (THA) is an effective and common procedure. However, persistent pain and analgesic requirement up to 2 years after THA surgery are common. We examined the trends in the utilization of analgesics before and after THA, overall, and in relation to socioeconomic status (SES) in a populationbased cohort. Patients and methods - We used the Danish Hip Arthroplasty Register to identify 103,209 patients who underwent THA between 1996 and 2018. Data on prescriptions and SES markers was obtained from Danish medical databases. Prevalence rates of redeemed prescriptions for analgesics with 95% confidence intervals were calculated for 4 quarters before and 4 quarters after THA for the entire THA population, and by 3 SES markers (education, cohabiting status, and wealth). Results - Overall, the prevalence of analgesic use prior to surgery was 42% at 9-12 months and 59% at 0-3 months before the THA. The prevalence of analgesics reached its highest at 64% 0-3 months after THA but declined to 27% at 9-12 months after THA. Low education, living alone, and having low wealth (low SES) were associated with higher prevalence of analgesics use both before and after THA. Interpretation - 59% of patients used analgesics 0-3 months before surgery, which could indicate that THA might not be considered the last option for treatment and that surgery criteria might depend more on factors such as patient preferences or hip function. Moreover, health professionals should prioritize the use of a detailed plan when phasing out analgesics after THA to counteract unnecessary use, especially when treating patients with low SES.

Do changes in outcomes following primary and revision hip replacement differ and relate to markers of socioeconomic status? A 1-year population-based cohort study.

BACKGROUND AND PURPOSE: There is little evidence on improvement after revision total hip replacement (THR). Moreover, improvements may be associated with socioeconomic status (SES). We investigated whether changes in Harris Hip Score (HHS) differ among patients undergoing primary and revision THR, and their association with markers of SES. PATIENTS AND METHODS: We conducted a populationbased cohort study on 16,932 patients undergoing primary and/or revision THR from 1995 to 2018 due to hip osteoarthritis. The patients were identified in the Danish Hip Arthroplasty Registry. Outcome was defined as mean change in HHS (0-100) from baseline to 1-year follow-up, and its association with SES markers (education, cohabiting, and wealth) was analyzed using multiple linear regression adjusting for sex, age, comorbidities, and baseline HHS. RESULTS: At 1-year follow-up, HHS improved clinically relevant for patients undergoing both primary THR: mean 43 (95% CI 43-43) and revision THR: mean 31 (CI 29-33); however, the increase was 12 points (CI 10-14) higher for primary THR. For primary THR, improvements were 0.9 points (CI 0.4-1.5) higher for patients with high educational level compared with low educational level, 0.4 points (CI 0.0-0.8) higher for patients cohabiting compared with living alone, and 2.6 points higher (CI 2.1-3.0) for patients with high wealth compared with low wealth. INTERPRETATION: Patients undergoing primary THR achieve higher improvements on HHS than patients undergoing revision THR, and the improvements are negatively related to markers of low SES. Health professionals should be aware of these characteristics and be able to identify patients who may benefit from extra rehabilitation to improve outcomes after THR to ensure equality in health.

The association between socioeconomic status and the 90-day risk of cardiovascular events after total hip arthroplasty - registry-based study of 103,286 patients.

BACKGROUND AND PURPOSE: Patients receiving a total hip arthroplasty (THA) are subsequently at an increased risk of cardiovascular disease (CVD). Further, socioeconomic status (SES) has an effect on CVD. We evaluated whether low SES is associated with a higher risk of readmission due to CVD after THA within 90 days in a setting with universal tax-supported healthcare. PATIENTS AND METHODS: We performed a nationwide population-based cohort study using Danish health registries from 1995 to 2017. Individual-based information on SES markers (cohabitation, education, income, and liquid assets) was obtained for all participants. The outcome was any hospital-treated CVD. The data was transformed using the pseudo-observation method to enable an estimation of the adjusted risk ratios (RRs) with 95% confidence intervals (CI) for each marker using generalized linear regression. RESULTS: Among 103,286 THA patients, 452 were hospitalized with CVD within 90 days after surgery. Low SES seemed to be associated with a small increased risk of CVD, as the RRs for any CVD were 1.1 (95% CI 0.7-1.7) for patients living alone vs. cohabiting, 1.3 (CI 0.7- .3) for low education vs. high, 1.4 (CI 0.8-2.6) for low income vs. high, and 1.3 (CI 0.8-2.1) for low liquid assets vs. high. CONCLUSION: Living alone, low education, low income, and low liquid assets seem to be associated with a small increased risk of readmission due to CVD 90 days after THA. Wide confidence intervals in risk should be considered when interpreting the study results.

Association between duration of anticoagulant thromboprophylaxis and revision rate in primary total hip arthroplasty: a Danish and Norwegian nationwide cohort study.

BACKGROUND AND PURPOSE: There are concerns that bleeding following primary total hip arthroplasty (THA) contributes to prolonged wound drainage and prosthetic joint infection (PJI). We examined whether short (1-5 days), medium (6-14 days), and extended (≥ 15 days) duration of thromboprophylaxis is associated with the 5-year revision rate after THA due to osteoarthritis. PATIENTS AND METHODS: We performed a cohort study based on data from hip arthroplasty and administrative registries in Denmark and Norway (2008-2014). The outcome was revision surgery due to PJI, aseptic loosening or any cause, and patient mortality. Adjusted cause-specific hazard ratios (HRs) were analyzed with Cox regression analyses. RESULTS: Among 50,482 THA patients, 8,333 received short, 17,009 received medium, and 25,140 received extended thromboprophylaxis. The HRs for revision due to PJI within 5 years were 1.0 (95%CI 0.7-1.3) and 1.1 (CI 0.9-1.3) for short and extended vs. medium treatment, whereas HR for extended vs. medium prophylaxis was 1.5 (CI 1.2-2.0) within 3 months. The HRs for revision due to aseptic loosening within 5 years were 1.0 (CI 0.7-1.4) and 1.1 (CI 0.9-1.4) for short and extended vs. medium treatment. The HRs for any revision within 5 years were 0.9 (CI 0.8-1.1) and 0.9 (CI 0.8-1.0) for short and extended vs. medium treatment. Extended vs. medium prophylaxis was associated with a decreased 0-3 month mortality. The absolute differences at 5 years were ≤ 1%. CONCLUSION: Our data suggests no association between duration of anticoagulant thromboprophylaxis and revision rate within 5 years of primary THA. The extended thromboprophylaxis might be associated with early increased revision rate due to PJI but also with lower mortality; however, the clinical relevance of this finding requires further research.

Impact of Nordic Arthroplasty Register Association (NARA) collaboration on demographics, methods and revision rates in knee arthroplasty: a register-based study from NARA 2000-2017.

BACKGROUND AND PURPOSE: We have previously observed differences in treatment and outcome of knee arthroplasties in the Nordic countries. To evaluate the impact of Nordic collaboration in the last 15 years we aimed to compare patient demographics, methods, and revision rates in primary knee arthroplasties among the 4 Nordic countries. PATIENTS AND METHODS: We included 535,051 primary knee arthroplasties reported 2000-2017 from the Nordic Arthroplasty Register Association (NARA) database. Kaplan-Meier analysis (KM) and restricted mean survival time (RMST) analysis were used to evaluate the cumulative revision rate (CRR) and RMST estimates with 95% confidence intervals (CI) and to compare countries in relation to risk of revision for any reason. RESULTS: After 2010, the increase in incidence of knee arthroplasty plateaued in Sweden and Denmark but continued to increase in Finland and Norway. In 2017 the incidence was highest in Finland with 226 per 105 person-years, while it was less than 150 per 105 in the 3 other Nordic countries. In total knee arthroplasties performed for osteoarthritis (OA), overall CRR at 15 years for revision due to any reason was higher in Denmark (CRR 9.6%, 95% CI 9.2-10), Norway (CRR 9.1%, CI 8.7-9.5), and Finland (CRR 7.0%, CI 6.8-7.3) compared with Sweden (CRR 6.6%, CI 6.4-6.8). There were differences among the countries in use of implant brand and type, fixation, patellar component, and use of unicompartmental knee arthroplasty. INTERPRETATION: We evinced a slowing growth of incidence of knee arthroplasties in the Nordic countries after 2010 with Finland having the highest incidence. We also noted substantial differences among the 4 Nordic countries, with Sweden having a lower risk of revision than the other countries. No impact of NARA could be demonstrated and CRR did not improve over time.

Cardiovascular risk and mortality in rheumatoid arthritis compared with diabetes mellitus and the general population.

OBJECTIVES: To compare risk of cardiovascular disease and mortality in patients with incident RA, diabetes mellitus (DM) and the general population (GP). METHODS: Patients diagnosed with incident RA were matched 1:5 by age, sex and year of RA diagnosis with the GP. In the same period, patients with incident DM were included. Outcomes were heart failure (HF), myocardial infarction (MI), coronary revascularization, stroke, major adverse cardiovascular events (MACE) and death up to 10 years after diagnosis. RESULTS: We included 15 032 patients with incident RA, 301 246 patients with DM and 75 160 persons from the GP. RA patients had an increased risk of HF [hazard ratio (HR) 1.51, 95% CI: 1.38, 1.64], MI (HR 1.58, 95% CI: 1.43, 1.74), percutaneous coronary intervention (PCI; HR 1.44, 95% CI: 1.27, 1.62), coronary artery bypass grafting (CABG; HR 1.30, 95% CI: 1.05, 1.62) and stroke (HR 1.22, 95% CI: 1.12-1.33) compared with the GP. However, the 10-year all-cause mortality was at the same level as observed in the GP. Cardiac death and MACE were increased in RA compared with the GP. When compared with patients with DM, RA patients had a lower adjusted risk of HF (HR 0.79, 95% CI: 0.73, 0.85), CABG (HR 0.62, 95% CI: 0.51, 0.76) and stroke (HR 0.82, 95% CI: 0.76, 0.89), and similar risk of MI and PCI. DM patients had the highest risk of 10-year mortality, cardiac death and MACE. CONCLUSION: This study demonstrates that RA is associated with an increased risk of HF, MI, stroke and coronary revascularization than found in the GP but without reaching the risk levels observed in DM patients.

Impact of socioeconomic status on the 90- and 365-day rate of revision and mortality after primary total hip arthroplasty: a cohort study based on 103,901 patients with osteoarthritis from national databases in Denmark.

Background and purpose - Socioeconomic inequality in health is recognized as an important public health issue. We examined whether socioeconomic status (SES) is associated with revision and mortality rates after total hip arthroplasty (THA) within 90 and 365 days.Patients and methods - We obtained SES markers (cohabitation, education, income, and liquid assets) on 103,901 THA patients from Danish health registers (year 1995-2017). The outcomes were any revision (all revisions), specified revision (due to infection, fracture, or dislocation), and mortality. We used Cox regression analysis to estimate adjusted hazard ratio (aHR) of each outcome with 95% confidence interval (CI) for each SES marker.Results - Within 90 days, the aHR for any revision was 1.3 (95% CI 1.1-1.4) for patients living alone vs. cohabiting. The aHR was 2.0 (CI 1.4-2.6) for low-income vs. high-income among patients < 65 years. The aHR was 1.2 (CI 0.9-1.7) for low liquid assets among patients > 65 years. Results were consistent for any revision within 365 days as well as for revisions due to infection, fracture, and dislocation. The aHR for mortality was 1.4 (CI 1.2-1.6) within 90 days and 1.3 (CI 1.2-1.5) within 365 days for patients living alone vs. cohabiting. Low education, low income, and low liquid assets were associated with increased mortality rate within both 90 and 365 days.Interpretation - Our results suggest that living alone, low income, and low liquid assets were associated with increased revision and mortality up to 365 days after THA surgery. Optimizing medical conditions prior to surgery and implementing different post-THA support strategies with a focus on vulnerable patients may reduce complications associated with inequality.