Elke Jeschke

Five-year Survival of 20,946 Unicondylar Knee Replacements and Patient Risk Factors for Failure: An Analysis of German Insurance Data

BACKGROUND Improvements in implant design and surgical technique of unicondylar knee arthroplasty have led to reduced revision rates, but patient selection seems to be crucial for success of such arthroplasties. The purpose of the present study was to analyze the 5-year implant survival rate of unicondylar knee replacements in Germany and to identify patient factors associated with an increased risk of revision, including >30 comorbid conditions. METHODS Using nationwide billing data of the largest German health-care insurance for inpatient hospital treatment, we identified patients who underwent unicondylar knee arthroplasty between 2006 and 2012. Kaplan-Meier survival curves with revision as the end point and log-rank tests were used to evaluate 5-year implant survival. A multivariable Cox regression model was used to determine factors associated with revision. The risk factors of age, sex, diagnosis, comorbidities, type of implant fixation, and hospital volume were analyzed. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were calculated. RESULTS During the study period, a total of 20,946 unicondylar knee arthroplasties were included. The number of unicondylar knee arthroplasties per year increased during the study period from 2,527 in 2006 to 4,036 in 2012. The median patient age was 64 years (interquartile range, 56 to 72 years), and 60.4% of patients were female. During the time evaluated, the 1-year revision rate decreased from 14.3% in 2006 to 8.7% in 2011. The 5-year survival rate was 87.8% (95% CI, 87.3% to 88.3%). Significant risk factors (p < 0.05) for unicondylar knee arthroplasty revision were younger age (the HR was 2.93 [95% CI, 2.48 to 3.46] for patient age of <55 years, 1.86 [95% CI, 1.58 to 2.19] for 55 to 64 years, and 1.52 [95% CI, 1.29 to 1.79] for 65 to 74 years; patient age of >74 years was used as the reference); female sex (HR, 1.18 [95% CI, 1.07 to 1.29]); complicated diabetes (HR, 1.47 [95% CI, 1.03 to 2.12]); depression (HR, 1.29 [95% CI, 1.06 to 1.57]); obesity, defined as a body mass index of ≥30 kg/m2 (HR, 1.13 [95% CI, 1.02 to 1.26]); and low-volume hospitals, denoted as an annual hospital volume of ≤10 cases (HR, 1.60 [95% CI, 1.39 to 1.84]), 11 to 20 cases (HR, 1.47 [95% CI, 1.27 to 1.70]), and 21 to 40 cases (HR, 1.31 [95% CI, 1.14 to 1.51]) (>40 cases was used as the reference). CONCLUSIONS Apart from known risk factors, this study showed a significant negative influence of obesity, depression, and complicated diabetes on the 5-year unicondylar knee replacement survival rate. Surgical indications and preoperative patient counseling should consider these findings. LEVEL OF EVIDENCE Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Mortality and Major Morbidity of Very-Low-Birth-Weight Infants in Germany 2008-2012: A Report Based on Administrative Data.

Background Expectant parents of very preterm infants, physicians, and policy makers require estimates for chances of survival and survival without morbidity. Such estimates should derive from a large, reliable, and contemporary data base of easily available items known at birth. Objective To determine short-term outcome and risk factors in very-low-birth-weight preterm infants based on administrative data. Methods Anonymized routine data sets transmitted from hospital administrations to statutory health insurance companies were used to assess survival and survival free of major morbidities in a large cohort of preterm infants in Germany. Results After exclusion of infants with lethal malformations, there were 13,147 infants with a birth weight below 1,500 g admitted to neonatal care 2008–2012, of whom 1,432 infants (10.9%) died within 180 days. Estimated 180 days survival probabilities were 0.632 (95% confidence interval 0.583–0.677) for infants with 250–499 g birth weight, 0.817 (0.799–0.834) for 500–749 g, 0.931 (0.920–0.940) for 750–999 g, 0.973 (0.967–0.979) for 1,000–1,249 g, and 0.985 (0.981–0.988) for 1,250–1,499 g. Estimated probabilities for survival without major morbidity (surgically treated intraventricular hemorrhage, necrotizing enterocolitis, intestinal perforation, or retinopathy) were 0.433 (0.384–0.481) for 250–499 g, 0.622 (0.600–0.643) for 500–749 g, 0.836 (0.821–0.849) for 750–999 g, 0.938 (0.928–0.946) for 1,000–1,249 g, and 0.969 (0.964–0.974) for 1,250–1,499 g, respectively. Prediction of survival and survival without major morbidities was moderately improved by adding sex, small for gestational age, and severe or moderate congenital malformation, increasing receiver operating characteristic areas under the curve from 0.839 (0.827–0.850) to 0.862 (0.852–0.874) (survival) and from 0.827 (0.822–0.842) to 0.852 (0.846–0.863) (survival without major morbidities), respectively. Conclusion The present analysis encourages attempts to use administrative data to investigate the association between risk factors and outcome in preterm infants.

Are TKAs Performed in High-volume Hospitals Less Likely to Undergo Revision Than TKAs Performed in Low-volume Hospitals?

BackgroundHigh-volume hospitals have achieved better outcomes for THAs and unicompartmental knee arthroplasties (UKAs). However, few studies have analyzed implant survival after primary TKA in high-volume centers.Questions/PurposesIs the risk of revision surgery higher when receiving a TKA in a low-volume hospital than in a high-volume hospital?MethodsUsing nationwide billing data of the largest German healthcare insurer for inpatient hospital treatment, we identified 45,165 TKAs in 44,465 patients insured by Allgemeine Ortskrankenkasse who had undergone knee replacement surgery between January 2012 and December 2012. Revision rates were calculated at 1 and 2 years in all knees. The hospital volume was calculated using volume quintiles of the number of all knee arthroplasties performed in each center. We used multiple logistic regression to model the odds of revision surgery as a function of hospital volume. Age, sex, 31 comorbidities, and variables for socioeconomic status were included as independent variables in the model.ResultsAfter controlling for socioeconomic factors, patient age, sex, and comorbidities, we found that having surgery in a high-volume hospital was associated with a decreased risk of having revision TKA within 2 years of the index procedure. The odds ratio for the 2-year revision was 1.6 (95% CI, 1.4–2.0; p < 0.001) for an annual hospital volume of 56 or fewer cases, 1.5 (95% CI, 1.3–1.7; p < 0.001) for 57 to 93 cases, 1.2 (95% CI, 1.0–1.3; p = 0.039) for 94 to 144 cases, and 1.1 (95% CI, 0.9–1.2; p = 0.319) for 145 to 251 cases compared with a hospital volume of 252 or more cases.ConclusionsWe found a clear association of higher risk for revision surgery when undergoing a TKA in a hospital where less than 145 arthroplasties per year were performed. The study results could help practitioners to guide potential patients in hospitals that perform more TKAs to reduce the overall revision and complication rates. Furthermore, this study underscores the importance of a minimum hospital threshold of arthroplasty cases per year to get permission to perform an arthroplasty.Level of EvidenceLevel III, therapeutic study.

Revascularisation of patients with end-stage renal disease on chronic haemodialysis: bypass surgery versus PCI-analysis of routine statutory health insurance data.

Objectives We aimed to analyse the short-term and long-term outcome of patients with end-stage renal disease (ESRD) undergoing percutaneous intervention (PCI) as compared to coronary artery bypass surgery (CABG) to evaluate the optimal coronary revascularisation strategy. Design Retrospective analysis of routine statutory health insurance data between 2010 and 2012. Main outcome measures Primary outcome was adjusted all-cause mortality after 30 days and major adverse cardiovascular and cerebrovascular events at 1 year. Secondary outcomes were repeat revascularisation at 30 days and 1 year and bleeding events within 7 days. Results The total number of cases was n=4123 (PCI; n=3417), median age was 71 (IQR 62–77), 30.4% were women. The adjusted OR for death within 30 days was 0.59 (95% CI 0.43 to 0.81) for patients undergoing PCI versus CABG. At 1 year, the adjusted OR for major adverse cardiac and cerebrovascular events (MACCE) was 1.58 (1.32 to 1.89) for PCI versus CABG and 1.47 (1.23 to 1.75) for all-cause death. In the subgroup of patients with acute myocardial infarction (AMI), adjusted all-cause mortality at 30 days did not differ significantly between both groups (OR 0.75 (0.47 to 1.20)), whereas in patients without AMI the OR for 30-day mortality was 0.44 (0.28 to 0.68) for PCI versus CABG. At 1 year, the adjusted OR for MACCE in patients with AMI was 1.40 (1.06 to 1.85) for PCI versus CABG and 1.47 (1.08 to 1.99) for mortality. Conclusions In this cohort of unselected patients with ESRD undergoing revascularisation, the 1-year outcome was better for CABG in patients with and without AMI. The 30-day mortality was higher in non-AMI patients with CABG reflecting an early hazard with surgery. In cases where the patients characteristics and risk profile make it difficult to decide on a revascularisation strategy, CABG could be the preferred option.

Einfluss der Fallzahl pro Klinik auf die 5-Jahres-Überlebensrate des unikondylären Kniegelenkersatzes in Deutschland

BACKGROUND Reported survival rates of unicondylar knee arthroplasty (UKA) vary considerably. The influences of patient characteristics and the type of implant have already been examined. This analysis investigated the influence of hospital volume on 5-year-survival rate, using administrative claims data of Germanys largest health insurance provider. METHODS We analysed administrative claims data for 20,946 UKAs covered by the German local healthcare funds (Allgemeine Ortskrankenkasse, AOK) between 2006 and 2012. Survival rates were estimated using Kaplan-Meier analysis. The influence of hospital case numbers on 5-year survival was analysed by means of multivariable Cox regression adjusted for patient characteristics. We estimated hazard ratios (HR) with 95% confidence intervals for five hospital volume categories: < 12 cases, 13 - 24 cases, 25 - 52 cases, 53 - 104 cases, > 104 cases (per hospital and year). RESULTS The overall 5-year Kaplan-Meier survival rate was 87.8% (95%-CI: 87.3 - 88.3%). This increased with hospital volume (< 12 cases: 84.1% vs. > 104 cases: 93.2%). The analysis identified low hospital volume as an independent risk factor for surgical revision (< 12 cases: HR = 2.13 [95%-CI 1.83 - 2.48]; 13 - 24 cases: HR = 1.94 [95%-CI: 1.67 - 2.25]; 25 - 52 cases: HR = 1.66 [95%-CI: 1.41 - 1.96]; 53 - 104 cases: HR = 1.51 [95%-CI: 1.28 - 1.77]; > 104 cases: reference category). DISCUSSION Our analysis revealed a significant relationship between hospital case numbers and 5-year survival rate, which increases with hospital volume. The risk of surgical revision within 5 years in hospitals with fewer than 25 UKAs per year is approximately twice as high as in hospitals with more than 104 cases.

Drug-eluting stents in clinical routine: a 1-year follow-up analysis based on German health insurance administrative data from 2008 to 2014

Objectives To describe the use of drug-eluting stents (DESs) in the largest population of statutory health insurance members in Germany, including newly developed bio-resorbable vascular scaffolds (BVSs), and to evaluate 1-year complication rates of DES as compared with bare metal stents (BMSs) in this cohort. Design Routine data analysis of statutory health insurance claims data from the years 2008 to 2014. Setting The German healthcare insurance Allgemeine Ortskrankenkasse covers approximately 30% of the German population and is the largest nationwide provider of statutory healthcare insurance in Germany. Participants and interventions We included all patients with a claims record for a percutaneous coronary intervention (PCI) with either DES or BMS and additionally, from 2013, BVS. Patients with acute myocardial infarction (AMI) were excluded. Main outcome measure: major adverse cerebrovascular and cardiovascular event (MACCE, defined as mortality, AMI, stroke and transient ischaemic attack), bypass surgery, PCI and coronary angiography) at 1 year after the intervention. Results A total of 243 581 PCI cases were included (DES excluding BVS: 143 765; BVS: 1440; BMS: 98 376). The 1-year MACCE rate was 7.42% in the DES subgroup excluding BVS and 11.29% in the BMS subgroup. The adjusted OR for MACCE was 0.72 (95% CI 0.70 to 0.75) in patients with DES excluding BVS as compared with patients with BMS. In the BVS group, the proportion of 1-year MACCE was 5.0%. Conclusion The analyses demonstrate a lower MACCE rate for PCI with DES. BVSs are used in clinical routine in selected cases and seem to provide a high degree of safety, but data are still sparse.

Qualitätssicherung mit Routinedaten (QSR)

Qualitatssicherung mit Routinedaten (QSR) ist ein Verfahren, um die Versorgungsqualitat von Kliniken messbar zu machen, ohne mehr Dokumentationsaufwand fur Arzte und Pflegepersonal zu erzeugen. QSR greift dazu auf administrative und Abrechnungsdaten von Kliniken und AOK zuruck, die sowieso erhoben werden mussen.