Development and validation of a code-based algorithm using in-hospital medical records to identify patients with pulmonary arterial hypertension in a French healthcare database.

Introduction: Pulmonary arterial hypertension (PAH) is a rare and severe disease for which most of the evidence about prognostic factors, evolution and treatment efficacy comes from cohorts, registries and clinical trials. We therefore aimed to develop and validate a new PAH identification algorithm that can be used in the French healthcare database "Système National des Données de Santé (SNDS)". Methods: We developed and validated the algorithm using the Grenoble Alpes University Hospital medical charts. We first identified PAH patients following a previously validated algorithm, using in-hospital ICD-10 (10th revision of the International Statistical Classification of Diseases) codes, right heart catheterisation procedure and PAH-specific treatment dispensing. Then, we refined the latter with the exclusion of chronic thromboembolic pulmonary hypertension procedures and treatment, the main misclassification factor. Second, we validated this algorithm using a gold standard review of in-hospital medical charts and calculated sensitivity, specificity, positive and negative predictive value (PPV and NPV) and accuracy. Finally, we applied this algorithm in the French healthcare database and described the characteristics of the identified patients. Results: In the Grenoble University Hospital, we identified 252 unique patients meeting all the algorithm's criteria between 1 January 2010 and 30 June 2022, and reviewed all medical records. The sensitivity, specificity, PPV, NPV and accuracy were 91.0%, 74.3%, 67.9%, 93.3% and 80.6%, respectively. Application of this algorithm to the SNDS yielded the identification of 9931 patients with consistent characteristics compared to PAH registries. Conclusion: Overall, we propose a new PAH identification algorithm developed and adapted to the French specificities that can be used in future studies using the French healthcare database.

Regional Heterogeneity of the Results of Glucagon-Like Peptide 1 Receptor Agonist Trials in Type 2 Diabetes: A Reanalysis of Individual Participant Data.

OBJECTIVE: Multiregional trials are designed under the assumption that treatment effect applies to the entire target population, yet several factors may introduce geographic heterogeneity in treatment effect. We explored whether such variations exist in trials assessing the efficacy of glucagon-like peptide 1 receptor agonists (GLP-1RAs) in major cardiovascular events (MACE) in type 2 diabetes. RESEARCH DESIGN AND METHODS: A systematic search of Medline and the Cochrane Library was conducted from inception until 30 June 2020. We included international randomized controlled trials comparing any GLP-1RA versus placebo, with MACE as a primary end point. Individual participant data were subsequently requested from the sponsor or through data sharing platforms. For each trial, we calculated hazard ratios (HRs) and their 95% CIs for MACE, subgrouped by region. We then performed a random-effects meta-analysis and conducted meta-regressions to assess the influence of predetermined variables of interest on treatment effect. RESULTS: We included six trials including 45,426 patients. Baseline risk of MACE ranged from 2.9 per 100 patient-years in Southern Asia to 7.4 per 100 patient-years in Sub-Saharan Africa. HRs for MACE ranged between 0.25 (95% CI 0.05, 1.12) in Northern Africa to 0.98 (0.79, 1.22) in Western Europe. There was no significant subgroup difference across regions (P = 0.70). Baseline risk of MACE and indexes of development status (i.e., Human Development Index, gross domestic product) were independently associated with GLP-1RA efficacy. CONCLUSIONS: This study does not suggest any regional heterogeneity of GLP-1RA efficacy in MACE. However, a higher baseline risk and lower development status were associated with a greater benefit of these drugs.

Use of Bisphosphonates and the Risk of Skin Ulcer: A National Cohort Study Using Data from the French Health Care Claims Database.

INTRODUCTION: Previous pre-clinical and pharmacovigilance disproportionality analyses highlighted a safety signal of cutaneous ulcer with bisphosphonate use. Therefore, our objective is to evaluate this risk and assess whether unmeasured confounding factors could explain this association. METHODS: This study is a population-based cohort study from a representative sample (1/97th) of the French health insurance claims database: Echantillon Généraliste des Bénéficiaires (EGB) from 2006 to 2019. To limit the impact of our study design and methodological choices on any association between skin ulceration and exposure to bisphosphonates, we used several methods: a Cox proportional hazards analysis and a prior event rate ratio (PERR) analysis, using two propensity matched control groups, and either the first episode of incident ulceration or multiple event-time outcomes. RESULTS: There were 7402 individuals newly exposed to bisphosphonates matched to 29,605 unexposed individuals on propensity score. The primary outcome was skin ulcer occurrence assessed by at least 2 deliveries of wound dressing during the period of one month. Among 6911 individuals newly exposed to bisphosphonates and 28,072 unexposed individuals with no previous skin ulcer, the Cox regression yielded a hazard ratio (HR) of 1.40 (95% CI 1.26-1.56) for newly exposed individuals. Among 7402 exposed and 29,605 unexposed individuals, the PERR analysis found a non-significant HR of 1.03 (95% CI 0.87-1.24). Results were similar on the different sensitivity analyses. CONCLUSION: No association between bisphosphonate and skin ulcers was found in the French population. The association observed in previous pharmacovigilance studies and in the Cox regression analysis is likely due to unmeasured confounding factors.

Placebo response in Raynaud's Phenomenon clinical trials: The prominent role of regression towards the mean: Placebo response in Raynaud's Phenomenon.

BACKGROUND: Substantial placebo response has been observed in trials assessing treatments in Raynaud's Phenomenon (RP), which makes any treatment effect difficult to detect. However, whether this response is due to a real placebo effect or to other nonspecific effects, such as regression towards the mean (RTM), has not been explored. Our objectives were to explore and quantify placebo response in RP, and to evaluate the magnitude of RTM contribution. METHODS: We combined trial-level and individual-level data from a series of n-of-1 trials and a network meta-analysis, respectively. Main outcomes were the daily frequency and the mean duration of RP attacks, as well as the Raynaud's Condition Score (RCS). We estimated the placebo response by the mean difference between the placebo period (or arm) and the baseline. RTM was estimated by the relationship between placebo response and baseline, and with Galton squeeze plots. Finally, we simulated the effect of the threshold used for inclusion in clinical trials on RTM. FINDINGS: We observed a large and significant placebo response from both individual and trial data for RCS [-1.20 (-1.63, -0.77) and -0.65 (-0.89, -0.41)] and the daily frequency of RP [-0.61 (-0.85, -0.37) and -0.75 (-0.95, -0.54)]. Outcome at baseline was significantly associated with placebo response, suggesting the presence of RTM. The latter was confirmed on individual data, through Galton squeeze plots. INTERPRETATION: Placebo response is large in RP trials, and likely due to regression towards the mean rather than 'true' placebo effect. This should be carefully considered when designing future trials. FUNDING: This work has been partially supported by MIAI @ Grenoble Alpes (ANR-19-P3IA-0003).