The Outcome of Laparoscopic Versus Open Appendectomy in Childhood.

BACKGROUND: Appendectomy in children is performed either lapa - roscopically (LA) or by open surgery (OA). We studied whether, and how, the outcome is affected by the technique used and by the intraoperative conversion of LA to OA. METHODS: We analyzed routine data from children and adolescents in three age groups (1-5 years, 6-12 years, and 13-17 years) who were insured by the AOK statutory health insurance carrier in Germany and who underwent appendectomy in the period 2017-2019. General surgical complications and reoperations within 90 days were assessed with relevant indicators. Associations between the surgical technique and these indicators were studied with logistic regression. RESULTS: Of the 21 541 patients included in the study, general surgical complications were observed in 2.1% and reoperations in 1.8% overall. Broken down by age group, the corresponding figures were 5.4% and 4.4% (age 1 to 5), 2.5% and 1.8% (age 6 to 12), and 1.5% and 1.6% (age 13 to 17). The main risk factors for complications and reoperations were acute complicated appendicitis and conversion from LA to OA. Regression analysis revealed similar outcomes with OA compared to LA in the 1-to-5 age group, (odds ratios and 95% confidence intervals: 1.1 [0.6; 2.1] for general surgical complications and 1.5 [0.8; 2.7] for reoperations), but worse outcomes with OA in the other two age groups (age 6 to 12: 1.9 [1.2; 2.9] and 2.1 [1.5; 2.9]; age 13 to 17: 1.7 [1.0; 2.9] and 2.2 [1.4; 3.6]). When conversions were assigned to the LA group, the odds ratio (OA compared to LA) for reoperation across all age groups was 3.5 [2.8; 4.4] in patients with acute uncomplicated appendicitis and 4.2 [3.4; 5.3] in patients with complicated appendicitis. Complicated appendicitis also increased the rate of general surgical complications and the length of stay in hospital. CONCLUSION: Among children in the two older age groups, LA was followed by fewer general surgical complications and reoperations than OA. These differences were less pronounced when conversions were counted as belonging to the LA group. Children aged 1-5 appear to benefit the least from the lapa - roscopic technique.

Oral anticoagulation in heart failure complicated by atrial fibrillation: A nationwide routine data study.

BACKGROUND: This nationwide routine data analysis evaluates if oral anticoagulant (OAC) use in patients with heart failure (HF) and atrial fibrillation (AF) leads to a lower mortality and reduced readmission rate. Superiority of new oral anticoagulants (NOACs), compared to vitamin K antagonists (VKA), was analyzed for these endpoints. METHODS: Anonymous data of patients with a health insurance at the Allgemeine Ortskrankenkasse and a claims record for hospitalization with the main diagnosis of HF and secondary diagnosis of AF (2017-2019) were included. A hospital stay in the previous year was an exclusion criterion. Mortality and readmission for all-cause and stroke/intracranial bleeding (ICB) were analyzed 91-365 days after the index hospitalization. Kaplan-Meier survival curves and multivariable Cox regression models were used to evaluate the impact of medication on outcome. RESULTS: 180,316 cases were included [81 years (IQR 76-86), 55.6% female, CHA2DS2-VASc score ≥ 2 (96.81%)]. In 80.6%, OACs were prescribed (VKA: 21.7%; direct factor Xa inhibitors (FXaI): 60.0%; direct thrombin inhibitors (DTI): 3.4%; with multiple prescriptions per patient included). Mortality rate was 19.1%, readmission rate was 29.9% and stroke/ICB occurred in 1.9%. Risk of death was lower with any OAC (HR 0.77, 95% CI [0.75-0.79]) but without significant differences in OAC type (VKA: HR 0.73, [0.71-0.76]; FXaI: HR 0.77, [0.75-0.78]; DTI: HR 0.71, [0.66-0.77]). The total readmission rate (HR 0.97, [0.94 to 0.99]) and readmission for stroke/ICB (HR 0.71, [0.65-0.77]) was lower with OAC. CONCLUSIONS: Nationwide data confirm a reduction in mortality and readmission rate in HF-AF patients taking OACs, without NOAC superiority.

Risk-related short-term clinical outcomes after transcatheter aortic valve implantation and their impact on early mortality: an analysis of claims-based data from Germany.

OBJECTIVES: We aimed to define and assess risk-specific adverse outcomes after transcatheter aortic valve implantation (TAVI) in an all-comers patient population based on German administrative claims data. METHODS: Administrative claims data of patients undergoing transvascular TAVI between 2017 and 2019 derived from the largest provider of statutory health-care insurance in Germany were used. Patients' risk profile was assessed using the established Hospital Frailty Risk (HFR) score and 30-day adverse events were evaluated. Multivariable logistic regression models were applied to investigate the relation of patients' risk factors to clinical outcomes and, subsequently, of clinical outcomes to mortality. RESULTS: A total of 21,430 patients were included in the analysis. Of those, 51% were categorized as low-, 37% as intermediate-, and 12% as high-risk TAVI patients according to HFR score. Whereas low-risk TAVI patients showed low rates of periprocedural adverse events, TAVI patients at intermediate or high risk suffered from worse outcomes. An increase in HFR score was associated with an increased risk for all adverse outcome measures. The strongest association of patients' risk profile and outcome was present for cerebrovascular events and acute renal failure after TAVI. Independent of patients' risk, the latter showed the strongest relation with early mortality after TAVI. CONCLUSIONS: Differentiated outcomes after TAVI can be assessed using claims-based data and are highly dependent on patients' risk profile. The present study might be of use to define risk-adjusted outcome margins for TAVI patients in Germany on the basis of health-insurance data.

Blood transfusion and venous thromboembolism trends and risk factors in primary and aseptic revision total hip and knee arthroplasties: A nationwide investigation of 736,061 cases.

BACKGROUND: Over the last years, new transfusion guidelines and pharmaceuticals have been introduced in primary and revision total hip and knee arthroplasty (P-THA, P-TKA, R-THA, R-TKA). In the US, a substantial decrease in transfusions has been observed in recent years. Little data exists on the subject in Europe. In this context we aimed to analyze: (1) Is there also a significant decrease in blood transfusion for these procedures in Germany? (2) Which patient and hospital related factors are associated with the risk of blood transfusion? (3) Is there a trend in complications, especially venous thromboembolism and stroke events that can be linked to tranexamic acid use? HYPOTHESIS: There is a significant trend in decreasing blood transfusions in hip and knee arthroplasty. METHODS: Using nationwide healthcare insurance data for inpatient hospital treatment, 736,061 cases treated between January 2011 and December 2017 were included (318,997 P-THAs, 43,780 R-THAs, 338,641 P-TKAs, 34,643 R-TKAs). Multivariable logistic regression was used to model the odds of transfusion as a function of the year of surgery. Adjusted odds ratios (OR) and 95% confidence intervals (CI) were calculated. RESULTS: In each cohort the odds of transfusion decreased over time (2017 vs. 2011 (reference): P-THA: OR 0.42 (95%CI: 0.39-0.45), P-TKA: OR 0.41 (95%CI: 0.37-0.46), R-THA: OR 0.52 (95%CI: 0.47-0.58), R-TKA: OR 0.53 (95%CI: 0.46-0.61). Patient-related risk factors for blood transfusion included older age, female gender, lower Body Mass Index, comorbidities such as renal failure, cardiac arrhythmia, congestive heart failure, valvular disease, coagulopathy, depression, and antithrombotic medication prior to surgery. Venous thromboembolism or stroke events did not increase over the study period. DISCUSSION: The incidence of blood transfusions in primary and revision TKA and THA decreased over the study period. This may be due to new transfusion guidelines and the introduction of novel pharmaceuticals such as tranexamic acid. A further improved patient blood management and a focus on vulnerable patient groups might lead to a further future reduction of transfusions, especially in R-THA. LEVEL OF EVIDENCE: III; comparative observational study.

Prevalence and Infant Mortality of Major Congenital Malformations Stratified by Birthweight.

BACKGROUND: Low birthweight and major congenital malformations (MCMs) are key causes of infant mortality. OBJECTIVES: The aim of this study was to explore the prevalence of MCMs in infants with low and very low birthweight and analyze the impact of MCMs and birthweight on infant mortality. METHODS: We determined prevalence and infant mortality of 28 life-threatening MCMs in very-low-birthweight (<1,500 g, VLBW), low-birthweight (1,500-2,499 g, LBW), or normal-birthweight (≥2,500 g, NBW) infants in a cohort of 2,727,002 infants born in Germany in 2006-2017, using de-identified administrative data of the largest statutory public health insurance system in Germany. RESULTS: The rates of VLBW, LBW, and NBW infants studied were 1.3% (34,401), 4.0% (109,558), and 94.7% (2,583,043). MCMs affected 0.5% (13,563) infants, of whom >75% (10,316) had severe congenital heart disease. The prevalence (per 10,000) of any/cardiac MCM was increased in VLBW (286/176) and LBW (244/143), as compared to NBW infants (38/32). Infant mortality rates were significantly higher in infants with an MCM, as opposed to infants without an MCM, in each birthweight group (VLBW 28.5% vs. 11.5%, LBW 16.7% vs. 0.9%, and NBW 8.6% vs. 0.1%). For most MCMs, observed survival rates in VLBW and LBW infants were lower than expected, as calculated from survival rates of VLBW or LBW infants without an MCM, and NBW infants with an MCM. CONCLUSIONS: Infants with an MCM are more often born with LBW or VLBW, as opposed to infants without an MCM. Many MCMs carry significant excess mortality when occurring in VLBW or LBW infants.

Time to Surgery and Outcome in the Treatment of Proximal Femoral Fractures.

BACKGROUND: It has not been conclusively established whether, or to what extent, the time to surgery affects mortality and the risk of complications after the surgical treatment of proximal femoral fractures. METHODS: Data on 106 187 hospitalizations over the period 2015-2017 involving insurees of the German AOK health insurance company aged 20 and above were drawn from pseudonymized billing data and stratified in three subgroups: osteosynthesis for pertrochanteric fracture (PTF-OS: N = 52 358), osteosynthesis for femoral neck fracture (FNF-OS: N = 7970), and endoprosthesis for femoral neck fracture (FNF-EP: N = 45 859). Multivariate regression models were used to analyze the relation between preoperative in-hospital stay (time to surgery, TTS: 0 days [reference category], 1, 2, 3, 4-7 days) and mortality and general complications within 90 days, with risk adjustment for fracture site, operative method, age, sex, accompanying illnesses, and antithrombotic medication in the preceding year. RESULTS: Mortality was significantly elevated only with PTF-OS, and only with a TTS of 2 days (odds ratio: 1.12 [95% confidence interval: (1.02; 1.23)]). General complications in relation to TTS were significantly elevated in the following situations: PTF-OS: 2 days: OR 1.24 [1.13; 1.37], 3 days: OR 1.33 [1.11; 1.60], 4-7 days: OR 1.47 [1.21; 1.78]; FNF-EP: 3 days: OR 1.21 [1.06; 1.37], 4-7 days: OR 1.42 [1.25; 1.62]; FNF-OS: 4-7 days: OR 1.86 [1.26; 2.73]. CONCLUSION: A prolonged time to surgery is associated with an elevated general complication risk depending on the site of the fracture and the type of surgical procedure used.

Impact of oral anticoagulation on clinical outcomes of COVID-19: a nationwide cohort study of hospitalized patients in Germany.

OBJECTIVES: The aim of this study was to investigate the impact of concomitant long-term medication-with a focus on ACE inhibitors and oral anticoagulation-on clinical outcomes in patients hospitalized with coronavirus disease 2019. METHODS: This is a retrospective cohort study using claims data of the biggest German health insurance company AOK, covering 26.9 million people all over Germany. In particular, patient-related characteristics and co-medication were evaluated. A multivariable logistic regression model was adopted to identify independent predictors for the primary outcome measure of all-cause mortality or need for invasive or non-invasive ventilation or extracorporeal membrane oxygenation. RESULTS: 6637 patients in 853 German hospitals were included. The primary outcome occurred in 1826 patients (27.5%). 1372 patients (20.7%) died, 886 patients (13.3%) needed respiratory support, and 53 patients (0.8%) received extracorporeal membrane oxygenation. 34 of these patients survived (64.2%). The multivariable model demonstrated that pre-existing oral anticoagulation therapy with either vitamin-K antagonists OR 0.57 (95% CI 0.40-0.83, p = 0.003) or direct oral anticoagulants OR 0.71 (95% CI 0.56-0.91, p = 0.007)-but not with antiplatelet therapy alone OR 1.10 (95% CI 0.88-1.23, p = 0.66)-was associated with a lower event rate. This finding was confirmed in a propensity match analysis. CONCLUSIONS: In a multivariable analysis, a therapy with both direct oral anticoagulants or vitamin-K antagonists-but not with antiplatelet therapy-was associated with improved clinical outcomes. ACE inhibitors did not impact outcomes. Prospective randomized trials are needed to verify this hypothesis.

Surgical Reintervention Rates after Invasive Treatment for Lower Urinary Tract Symptoms due to Benign Prostatic Syndrome: A Comparative Study of More than 43,000 Patients with Long-Term Followup.

PURPOSE: No large-scale comparison of the 4 most established surgical approaches for lower urinary tract symptoms due to benign prostate obstruction in terms of long-term efficacy is available. We compared photoselective vaporization, laser enucleation and open simple prostatectomy to transurethral resection with regard to 5-year surgical reintervention rates. MATERIALS AND METHODS: A total of 43,041 male patients with lower urinary tract symptoms who underwent transurethral resection (34,526), photoselective vaporization (3,050), laser enucleation (1,814) or open simple prostatectomy (3,651) between 2011 and 2013 were identified in pseudonymized claims and core data of the German local health care funds and followed for 5 years. Surgical reinterventions for lower urinary tract symptoms, urethral stricture or bladder neck contracture were evaluated. Surgical approach was related to reintervention risk using the Kaplan-Meier method and Cox proportional hazards models. RESULTS: A total of 5,050 first reinterventions were performed within 5 years of primary surgery (Kaplan-Meier survival without reintervention: 87.5%, 95% CI 87.2%-87.8%). Photoselective vaporization carried an increased hazard of reintervention (HR 1.31, 95% CI 1.17-1.46, p <0.001) relative to transurethral resection, open simple prostatectomy carried a lower hazard (HR 0.43, 95% CI 0.37-0.50, p <0.001) and laser enucleation of the prostate did not differ significantly (HR 0.84, 95% CI 0.66-1.08, p=0.2). This pattern was more pronounced regarding reintervention for lower urinary tract symptom recurrence (photoselective vaporization: HR 1.52, 95% CI 1.35-1.72, p <0.001; laser enucleation of the prostate: HR 0.84, 95% CI 0.63-1.14, p=0.3; open simply prostatectomy: HR 0.38, 95% CI 0.31-0.46, p <0.001 relative to transurethral resection). CONCLUSIONS: Five-year reintervention rates of transurethral resection and laser enucleation did not differ significantly, while photoselective vaporization had a substantially higher rate. Open simple prostatectomy remains superior to transurethral resection with respect to long-term efficacy.

Rates of Complications After Appendectomy in Children and Adolescents: Pediatric Surgical Compared to General Surgical Hospitals.

BACKGROUND: Appendectomies in children and adolescents are performed in Germany in pediatric surgical (PS) or general surgical hospitals (GS). The aim of this study is to evaluate whether the surgery in a PS or GS hospital has an influence on the postoperative course after appendectomy in children and adolescents. MATERIALS AND METHODS: Nationwide routine data from children and adolescents aged 1-17 y insured by the Local Health Insurance Fund who underwent appendectomy between 2014 and 2016 were analyzed (cohort study). Descriptive statistics were calculated both overall and in the two groups (PS and GS). Patients were additionally examined by age (1-5, 6-12, and 13-17 y), treatment (laparoscopic, open surgical, and conversion), and appendicitis type (nonacute: K36/K37/K38/R10, acute simple: K35.30/K35.8, and acute complex: K35.2/K35.31/K35.32). The influence of surgeon specialization on 90-d secondary surgery and 90-d general complications was assessed by multiple logistic regression. RESULTS: Altogether, 25,065 patients who underwent surgery in 83 PS and 906 GS hospitals were included. Logistic regression analysis revealed that PS was associated with a reduced risk of interventions in the 1-5- and 6-12-y age groups (odds ratio: 0.44, 0.62). Acute complex appendicitis, comorbidities, and open surgery significantly increased the risk for reintervention. PS was associated with an increased risk for complications in the 13-17-y age group (odds ratio: 1.66). CONCLUSIONS: PS and GS hospitals provided safe appendectomies in children and adolescents with low reintervention and complication rates. PS hospitals demonstrated advantages for patients in the 1-5- and 6-12-y age groups and GS hospitals for patients 13-17 y.

Low Hospital Volume Increases Re-Revision Rate Following Aseptic Revision Total Knee Arthroplasty: An Analysis of 23,644 Cases.

BACKGROUND: Along with rising numbers of primary total knee arthroplasty (TKA), the number of revision total knee arthroplasties (R-TKAs) has been increasing. R-TKA is a complex procedure requiring special instruments, implants, and surgical skills. Therefore it is likely that hospitals with more R-TKAs have more experience with this type of surgery and therefore fewer complications. The purpose of this study is to evaluate the relationship between hospital volume and re-revision rate following R-TKA. METHODS: Using nationwide healthcare insurance data for inpatient hospital treatment, 23,644 aseptic R-TKAs in 21,573 patients treated between January 2013 and December 2017 were analyzed. Outcomes were 90-day mortality, 1-year re-revision rate, and in-house adverse events. The effect of hospital volumes on outcomes were analyzed by means of multivariate logistic regression. Adjusted odds ratios (OR) and 95% confidence intervals (CI) were calculated. RESULTS: Hospital volume had a significant effect on 1-year re-revision rate (≤12 R-TKA/a: OR 1.44, CI 1.20-1.72; 13-24 R-TKA/a: OR 1.43, CI 1.20-1.71; 25-52 R-TKA/a: OR 1.13, CI 0.94-1.35; ≥53 R-TKA/a: reference). Ninety-day mortality and major in-house adverse events decreased with increasing volume per year, but after risk adjustment this was not statistically significant. CONCLUSION: We found evidence of higher risk for re-revision surgery in hospitals with fewer than 25 R-TKA per year. It might contribute to improved patient care if complex elective procedures like R-TKA which require experience and a specific logistic background were performed in specialized centers.

Low Hospital Volume Increases Revision Rate and Mortality Following Revision Total Hip Arthroplasty: An Analysis of 17,773 Cases.

BACKGROUND: With the number of primary total hip arthroplasty (THA), the amount of revision THA (R-THA) increases. R-THA is a complex procedure requiring special instruments, implants, and surgical skills. Therefore it is likely that hospitals performing a higher number of R-THAs have more experience with this type of surgery and therefore fewer complications. The purpose of this study was to evaluate the relationship between hospital volume and risk of postoperative complications following R-THA. METHODS: Using nationwide healthcare insurance data for inpatient hospital treatment, 17,773 aseptic R-THAs in 16,376 patients treated between January 2014 and December 2016 were included. Outcomes were 90-day mortality, 1-year revision procedures, and in-house adverse events. The effect of hospital volume on outcome was analyzed by means of multivariate logistic regression. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. RESULTS: Hospital volume had a significant effect on 90-day mortality (≤12 cases per year: OR 2.13, CI 1.53-2.96; 13-24: OR 1.79, CI 1.29-2.50; 25-52: OR 1.53, CI 1.11-2.10; ≥53: reference) and 1-year revision procedures (≤12: OR 1.26, CI 1.09-1.47; 13-24: OR 1.18, CI 1.02-1.37; 25-52: OR 1.03, CI 0.90-1.19; ≥53: reference). There was no significant effect on risk-adjusted major in-house adverse events. CONCLUSION: We found evidence of higher risk for revision surgery and mortality in hospitals with fewer than 25 and 53 R-THA per year, respectively. To improve patient care, complex elective procedures like R-THA which require experience and a specific logistic background should be performed in specialized centers.

[Quality Assurance Using Administrative/Routine Data for Cholelithiasis - Changes Over Time and Current Status]. / Qualitätssicherung mit Routinedaten bei Cholelithiasis ­ Veränderungen und aktueller Stand.

Quality assurance using administrative/routine data (QSR) is a relatively new measure to assess outcome quality. This approach is methodologically distinct from external quality assurance, as well as from quality assurance based upon registries. Since 2011, QSR for cholelithiasis within AOK patients has been overseen by the Scientific Institute of the AOK (WIdO). Following the introduction of an expert panel in 2013, numerous changes were put into place, whereby the indicator rates for transfusion/bleeding, various complications as well as the overall indicator were reduced. Interestingly, the risk adjusted quality differences between hospitals remained solid.

Obesity Increases the Risk of Postoperative Complications and Revision Rates Following Primary Total Hip Arthroplasty: An Analysis of 131,576 Total Hip Arthroplasty Cases.

BACKGROUND: The aim of our study is to evaluate the association of body mass index (BMI) and the risk of postoperative complications, mortality, and revision rates following primary total hip arthroplasty given other potentially confounding patient characteristics in a large cohort study. METHODS: Using nationwide billing data for inpatient hospital treatment of the biggest German healthcare insurance, 131,576 total hip arthroplasties in 124,368 patients between January 2012 and December 2014 were included. Outcomes were 90-day mortality, 1-year revision procedures (with and without removal or exchange of implants), 90-day surgical complications, 90-day femoral fractures, and overall complications. The effect of BMI on outcome was analyzed using multivariable logistic regression. Risk-adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. RESULTS: BMI had a significant effect on overall complications (30-34 in kg/m2: OR 1.1, CI 1.0-1.2, P = .014; 35-39: OR 1.5, CI 1.3-1.6, P < .001; ≥40: OR 2.1, CI 1.9-2.3, P < .001; <30: reference). The OR for 1-year revision procedures (30-34: OR 1.2, CI 1.1-1.4, P = .001; 35-39: OR 1.6, CI 1.4-1.8, P < .001; ≥40: OR 2.4, CI 2.1-2.7, P < .001; <30: reference) and 90-day surgical complications increased with every BMI category. For mortality and periprosthetic fractures there was a higher risk only for patients with BMI ≥40. CONCLUSION: BMI increases the risk of revision rates in a liner trend. Therefore, the authors believe that patients with a BMI >40 kg/m2 should be sent to obesity medicine physicians in order to decrease the body weight prior elective surgery.

[Impact of Case Numbers on the 5-Year Survival Rate of Unicondylar Knee Replacements in Germany]. / 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 Germany's 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.

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

BACKGROUND: High-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/PURPOSES: Is the risk of revision surgery higher when receiving a TKA in a low-volume hospital than in a high-volume hospital? METHODS: Using 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. RESULTS: After 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. CONCLUSIONS: We 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 EVIDENCE: Level III, therapeutic study.

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.

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.

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 patient's characteristics and risk profile make it difficult to decide on a revascularisation strategy, CABG could be the preferred option.

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.