Prevalence of total knee arthroplasty and its predictive factors in Japanese patients with rheumatoid arthritis: Analysis using the NinJa cohort.

OBJECTIVES: The aim of this study was to clarify the prevalence and the predictive factors for undergoing total knee arthroplasty (TKA) among patients with rheumatoid arthritis (RA). METHODS: The data of 1,134 patients with RA who were enrolled in the Japanese nationwide cohort database NinJa in 2003 and consecutively followed up until 2009 were analyzed. RESULTS: Seventy-six patients underwent TKA during the observation period. The yearly progression of the modified Health Assessment Questionnaire or mHAQ score from 2003 to 2004, but not the yearly progression of the Disease Activity Score in 28 Joints or DAS28 or patient visual analog scale (VAS) score, was significantly higher in the patients who underwent TKA than those who did not. Multivariate analysis showed that knee involvement in the disease, high Steinbrocker stage (III or IV), and high patient VAS score at the time of enrollment were powerful predictive factors, with hazard ratios of 4.01, 3.71, and 1.20, respectively. According to survival analysis with TKA as an endpoint, patients with knee involvement in the disease at the time of enrollment had a significantly worse 5-year survival rate than did those without knee involvement (83.5% vs. 97.0%, respectively). CONCLUSION: Several factors were elucidated as predictive factors for undergoing TKA among patients with RA.

Prophylactic effect of fondaparinux and enoxaparin for preventing pulmonary embolism after total hip or knee arthroplasty: A retrospective observational study using the Japanese Diagnosis Procedure Combination database.

OBJECTIVES: The aim of this study was to estimate the effect of fondaparinux and enoxaparin combined with mechanical prophylaxis (MP) after total hip arthroplasty (THA) and total knee arthroplasty (TKA). We also investigated the occurrence of pulmonary embolism (PE) and its associated risk factors. METHODS: Data were retrospectively collected on patients who underwent THA or TKA between 2008 and 2010 from the Japanese Diagnosis Procedure Combination database (n = 49,678). We extracted information on sex, age, main diagnosis, types of anesthesia, duration of anesthesia, comorbidities, hospital volume, the use of MP, and the use of anticoagulant drugs. RESULTS: The overall occurrence of PE was 0.41%. Multivariate logistic regression analysis showed that the occurrence of PE was significantly higher in females (odds ratio, 2.17; p < 0.001, compared with males), TKA (1.47; p = 0.039, compared with THA), and longer-duration anesthesia (2.63; p = 0.008 in the ≥ 240-min. group compared with the ≤ 119-min. group). Compared with the MP-alone group, the occurrence of PE was significantly reduced in the fondaparinux group (0.58; p = 0.025) and the enoxaparin group (0.59; p = 0.046). CONCLUSIONS: Fondaparinux or enoxaparin combined with MP decreased the occurrence of PE. The risk factors for PE were female patients, TKA, and longer-duration anesthesia (≥ 240 min.).

Risk factors affecting inhospital mortality after hip fracture: retrospective analysis using the Japanese Diagnosis Procedure Combination Database.

OBJECTIVE: To identify risk factors for inhospital mortality in patients with hip fractures using the Japanese Diagnosis Procedure Combination (DPC) nationwide administrative claims database. DESIGN: Retrospective observational study. SETTING: Hospitals adopting the DPC system during 2007-2009. PARTICIPANTS: The authors analysed a total of 80 800 eligible patients aged ≥60 years with a single hip fracture (International Classification of Diseases, 10th Revision codes: S72.0 and S72.1). The DPC database includes patients treated between July and December each year. MAIN OUTCOME MEASURES: Inhospital mortality after hip fracture. RESULTS: The overall inhospital mortality rate after hip fractures was 3.3%. Multivariate analysis indicated that inhospital mortality was significantly associated with male gender (OR 2.12, 95% CI 1.94 to 2.31), advancing age and number of comorbidities. Significantly higher mortality was observed in those treated conservatively (OR 4.25, 95% CI 3.92 to 4.61). Surgical delays of 5 days or more were significantly associated with higher rates of inhospital mortality (OR 1.34, 95% CI 1.20 to 1.50). CONCLUSIONS: In patients with hip fractures, male gender, advancing age, high number of comorbidities, conservative treatment and the surgical delay of 5 days or more were associated with higher rates of inhospital mortality.

Risk factors for pulmonary embolism and the effects of fondaparinux after total hip and knee arthroplasty: a retrospective observational study with use of a national database in Japan.

BACKGROUND: Clinical evidence demonstrating the effectiveness of pharmacological and mechanical thromboprophylaxis for the prevention of pulmonary embolism is limited because the prevalence of postoperative pulmonary embolism following total hip and knee arthroplasty is very low. Our purposes were to characterize a patient population with in-hospital pulmonary embolism, to identify perioperative risk factors associated with pulmonary embolism, and to analyze the effect of combining fondaparinux with mechanical prophylaxis on the prevalence of pulmonary embolism following total hip and knee arthroplasty. METHODS: We retrospectively identified 27,542 patients who underwent total hip or knee arthroplasty at 793 hospitals, using data from the Diagnosis Procedure Combination database, collected from July 1 to December 31 in 2007 and 2008. We extracted data on patient sex, age, primary diagnoses, and comorbidities that could potentially affect the prevalence of pulmonary embolism. The dates of pharmacological and mechanical thromboprophylaxis were identified for each patient. Logistic regression analysis was performed to analyze the concurrent effects of various factors on the prevalence of postoperative pulmonary embolism. RESULTS: The mean age (and standard deviation) of the patients at the time of arthroplasty was 69.9 ± 10.3 years, and 23,783 patients (86.4%) were diagnosed as having osteoarthritis. The overall mean duration of anesthesia was 159 ± 84 minutes. The overall prevalence of postoperative pulmonary embolism was 0.55% (151 of 27,542). Significant risk factors for postoperative pulmonary embolism included age, number of comorbidities, diagnosis of rheumatoid arthritis, type of anesthesia, and duration of anesthesia. Multivariate analysis found that the prevalence of postoperative pulmonary embolism was significantly reduced when fondaparinux was used in combination with mechanical prophylaxis, compared with the use of mechanical prophylaxis alone (0.40% versus 0.66%; odds ratio, 0.60; 95% confidence interval, 0.42 to 0.84; p = 0.003). CONCLUSIONS: These findings could help to identify patients at higher risk of postoperative pulmonary embolism after total hip or knee arthroplasty. Our results demonstrate the effectiveness of fondaparinux in combination with mechanical prophylaxis for the prevention of postoperative pulmonary embolism after total hip or knee arthroplasty.