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Background Diagnosis performances of case-identifying algorithms developed in healthcare database are usually assessed by comparing identified cases with an external data source. When this is not feasible, intra-database validation can present an appropriate alternative. Objectives To illustrate through two practical examples how to perform intra-database validations of case-identifying algorithms using reconstituted Electronic Health Records (rEHRs). Methods Patients with 1) multiple sclerosis (MS) relapses and 2) metastatic castration-resistant prostate cancer (mCRPC) were identified in the French nationwide healthcare database (SNDS) using two case-identifying algorithms. A validation study was then conducted to estimate diagnostic performances of these algorithms through the calculation of their positive predictive value (PPV) and negative predictive value (NPV). To that end, anonymized rEHRs were generated based on the overall information captured in the SNDS over time (e.g. procedure, hospital stays, drug dispensing, medical visits) for a random selection of patients identified as cases or non-cases according to the predefined algorithms. For each disease, an independent validation committee reviewed the rEHRs of 100 cases and 100 non-cases in order to adjudicate on the status of the selected patients (true case/ true non-case), blinded with respect to the result of the corresponding algorithm. Results Algorithm for relapses identification in MS showed a 95% PPV and 100% NPV. Algorithm for mCRPC identification showed a 97% PPV and 99% NPV. Conclusion The use of rEHRs to conduct an intra-database validation appears to be a valuable tool to estimate the performances of a case-identifying algorithm and assess its validity, in the absence of alternative.

Resection of metastases after chemotherapy improves survival outcomes of patients with initially inoperable metastatic colorectal cancer (mCRC), yet little data is available for those treated in the first-line setting with bevacizumab plus irinotecan. To provide data on this, the present study described the subgroup of the ETNA cohort who underwent metastases surgery. The population of operated patients was described according to metastatic site (exclusively hepatic, non-exclusively hepatic, and non-hepatic). Factors associated with overall survival (OS) and progression-free survival (PFS) were evaluated using multivariable Cox analysis. A total of 76 patients (21.1 % of the ETNA cohort) underwent metastases resection: 50 % male, median age 61.9 years, 85.5 % ECOG ≤ 1, and median duration of bevacizumab use 7.2 months. No surgery-related deaths were observed and 30.6 % of patients had at least one post-operative complication, mainly infections (11.8 % of resections), bleeding complications (3.5 %), or delayed wound healing (2.4 %). Complete remission was higher for those with exclusively hepatic metastases (22/32, 68.8 %) than those with non-exclusively hepatic metastases (12/24, 50.0 %), or non-hepatic metastases (12/20, 60.0 %). Among operated patients, 52.6 % had died after 5 years of follow-up. In multivariable analysis at 2 years of follow-up, death (HR 0.09 [95 % CI 0.02-0.35]) and progression (HR 0.35 [95 % CI 0.23-0.56]) were less likely for patients with complete remission (CR) after surgery R0-R1 or radiofrequency ablation (RFA) [CR RFA] compared with those who were not resected or with R2 resection. In real-life practice, bevacizumab with irinotecan in first-line therapy for mCRC allows secondary resection of metastases and survival is more favourable in those with complete remission (R0-R1/CR RFA).

BACKGROUND: Several methods have been proposed to assess causality in drug-induced liver injury but none have been tested in the specific context of acute liver failure leading to transplantation (ALFT). OBJECTIVE: We took advantage of the Study of Acute Liver Transplant (SALT), a European case-population study of ALFT, to test different causality scales. METHODS: Causality was assessed by experts in SALT, a 7-country case-population study from 2005 to 2007 of adult otherwise unexplained ALFT, for all drugs found within 30 days prior to the date of initial symptoms of liver disease (index date), using information content, causality scales, and data circuit determined from a pilot study, Salome. RESULTS: The consensus points from Salome were to provide full data on drugs including international non-proprietary name (INN) and doses except for non-steroidal anti-inflammatory drugs (NSAIDs) and to use the World Health Organization (WHO) causality scale. In SALT, among the 9,479 identified patients, 600 (6.3 %) were cases of ALFT, of which 187 had been exposed to drugs within 30 days, without overdose. In 130 (69.5 %) of these the causality score was possible, probable, or highly probable. CONCLUSION: In ALFT cases, once other clinical causes have been excluded and drug exposure established within 30 days, the main discriminant characteristic for causality will be previous knowledge of possible hepatotoxicity.

Background Most NSAIDs are thought to be able to cause hepatic injury and acute liver failure (ALF), but the event rates of those leading to transplantation (ALFT) remain uncertain. Objectives The aim of the study was to estimate population event rates for NSAID-associated ALFT Methods This was a case-population study of ALFT in 57 eligible liver transplant centres in seven countries (France, Greece, Ireland, Italy, The Netherlands, Portugal and the UK). Cases were all adults registered from 2005 to 2007 for a liver transplant following ALFT without identified clinical aetiology, exposed to an NSAID or paracetamol (acetaminophen) within 30 days before the onset of clinical symptoms. NSAID and paracetamol population exposures were assessed using national sales data from Intercontinental Marketing Services (IMS). Risk was estimated as the rate of ALFT per million treatment-years (MTY). Results In the 52 participating centres, 9479 patients were registered for transplantation, with 600 for ALFT, 301 of whom, without clinical aetiology, had been exposed to a drug within 30 days. Of these 301 patients, 40 had been exposed to an NSAID and 192 to paracetamol (81 of whom were without overdose). Event rates per MTY were 1.59 (95 % CI 1.1–2.2) for all NSAIDs pooled, 2.3 (95 % CI 1.2–3.9) for ibuprofen, 1.9 (95 % CI 0.8–3.7) for nimesulide, 1.6 (95 % CI 0.6–3.4) for diclofenac and 1.6 (95 % CI 0.3–4.5) for ketoprofen. For paracetamol, the event rate was 3.3 per MTY (95 % CI 2.6–4.1) without overdoses and 7.8 (95 % CI 6.8–9.0) including overdoses. Conclusions ALF leading to registration for transplantation after exposure to an NSAID was rare, with no major difference between NSAID. Non-overdose paracetamol-exposed liver failure was twice more common than NSAID-exposed liver failure. Electronic supplementary material The online version of this article (doi:10.1007/s40264-012-0013-7) contains supplementary material, which is available to authorized users.