Félicitation à Jonas Poucineau pour sa thèse

réalisée sous la direction de Myriam Khlat et Sophie Le Cœur, Directrices de recherche à l'Ined.

The COVID-19 pandemic has led to a reorganisation of healthcare provision in France, with implications for healthcare use and health outcomes in patients suffering from chronic conditions. This doctoral thesis aims to analyse, using medical-administrative data from the French National Health Data System (SNDS), the direct and indirect effects of the health crisis on patients with two lung diseases: chronic obstructive pulmonary disease (COPD) and lung cancer. Through various methodological approaches, it seeks to investigate patient mortality and healthcare use during the pandemic period, in comparison with the pre-pandemic period, taking into account temporal and seasonal trends. The two study pathologies, COPD and lung cancer, with their differences in clinical profiles, speed of disease progression and patterns of healthcare use, enable the analysis of the effects of the pandemic from complementary perspectives.

The first section of the thesis focuses on hospital admissions for acute COPD exacerbations between 2016 and 2023. It shows that the number of stays fell sharply during the pandemic, until autumn 2022, and that the in-hospital mortality rate increased concomitantly. The results suggest changes in patterns of healthcare use and a reduction in the incidence of exacerbations, due to less exposure to respiratory viruses.

The second section analyses the mortality of COPD patients between 2017 and 2020, compared with a control population. In 2020, COPD patients experienced a smaller increase in all-cause mortality, despite having a two-fold higher COVID-19 mortality rate. Non-Covid-19 mortality fell in COPD patients, reflecting a possible harvesting effect and a probable protective effect of health measures.
The third section explores trends in the number of lung cancer diagnoses and all-cause mortality between 2013 and 2021. It reveals a shortfall in the number of incident cases during the first pandemic wave compared with predictions based on pre-pandemic trends, with no catch-up in the following months, indicating that some patients may have died before being diagnosed. A slight excess mortality was observed in patients diagnosed during this period, illustrating a possible adverse effect of delays in diagnosis due to hospital overcrowding.

Pr. Nicolas Roche, PU-PH, Université Paris Cité-Hôpital Cochin (Président)
Dr. Philippe-Jean Bousquet, Directeur général, GIP CAD (Rapporteur et examinateur)
Pr. Olivier Robineau, PU-PH, Université de Lille ( Rapporteur et examinateur)
Dr. Moussa Laanani, Médecin épidémiologiste, CNAM (Examinateur)
Dr. Myriam Khlat, Directrice de rechereche (Co-directrice de thèse)
Dr. Sophie Le Cœur, Directrice de rechereche (Co-directrice de thèse)

Jonas Poucineau [Researcher’s page]