Obesity is a major and increasingly global public health issue.¹ More than half of the European population is overweight or obese.² In 2016, the World Health Organization estimated the prevalence of obesity as 21.6% (95% CI, 17.4%-25.9%) in France.³ The causal association between obesity and cancer has been well documented,⁴ and the obesity epidemic is suspected to accelerate the development of several cancers.⁵ Bariatric surgery is considered the most effective treatment of morbid obesity, providing sustained long-term weight loss⁶ and remission or improvement of obesity-related comorbidities.^7,8 Bariatric surgery has also been shown to reduce cancer incidence in women with morbid obesity in a randomized clinical trial,⁹ and to be associated with reduced mortality in a controlled cohort study.¹⁰ Recent observational studies have suggested that bariatric surgery may lower the risk of incident obesity-associated cancer.^11,12 However, unexpectedly, other studies do not confirm this benefit. On the contrary, the results of some observational studies have suggested an increased risk of colorectal cancer (CRC) following bariatric surgery;^13,14 1 study observed this increase only among patients who were 50 years or older,¹⁵ and another only after gastric bypass.¹⁶ However, there were few cases of CRC in these reports likely because of the younger age of the participants relative to the median age of patients receiving a CRC diagnosis and the time of follow-up required before a tumor develops and becomes clinically manifest.^17,18 Because the prevalence of obesity increases after 60 years of age in European countries² as in other Western countries,¹⁹ we decided to follow-up all French patients with a diagnosis of obesity confirmed during a hospitalization and of CRC screening age, which in France is 50 to 75 years of age,²⁰ invited since 2009 to a large national CRC screening program. In 2018, the cumulative number of patients who underwent bariatric surgery in France was estimated to exceed 500 000 individuals²¹ for whom long-term follow-up is recommended.²² However, because the mean (SD) patient age was 40 (12) years for those who had undergone bariatric surgery in 2013,²³ a large database was required to include sufficient patients within the CRC screening age range. The French national health insurance information system database is among the largest medical databases worldwide.²⁴ Thus, the aim of the present study was to use this database to investigate the risk of CRC among patients who were morbidly obese and who underwent bariatric surgery and to compare this risk with that among individuals with morbid obesity who did not undergo this surgery.

Dysregulated immune response is the key factor leading to unfavorable coronavirus disease 2019 (COVID-19) outcome. Depending on the pathogen-associated molecular pattern, the NLRP3 inflammasome can play a crucial role during innate immunity activation. To date, studies describing the NLRP3 response during severe acute respiratory syndrome coronavirus 2 infection in patients are lacking. We prospectively monitored caspase-1 activation levels in peripheral myeloid cells from healthy donors and patients with mild to critical COVID-19. The caspase-1 activation potential in response to NLRP3 inflammasome stimulation was opposed between nonclassical monocytes and CD66b+CD16dim granulocytes in severe and critical COVID-19 patients. Unexpectedly, the CD66b+CD16dim granulocytes had decreased nigericin-triggered caspase-1 activation potential associated with an increased percentage of NLRP3 inflammasome impaired immature neutrophils and a loss of eosinophils in the blood. In patients who recovered from COVID-19, nigericin-triggered caspase-1 activation potential in CD66b+CD16dim cells was restored and the proportion of immature neutrophils was similar to control. Here, we reveal that NLRP3 inflammasome activation potential differs among myeloid cells and could be used as a biomarker of a COVID-19 patient’s evolution. This assay could be a useful tool to predict patient outcome. This trial was registered at www.clinicaltrials.gov as #NCT04385017.

Reliable epidemiological data on Alzheimer's disease are scarce. However, these are necessary to adapt healthcare policy in terms of prevention, care and social needs related to this condition. To estimate the prevalence rate in the Alpes-Maritimes on the French Riviera, with a population of one million, we present a capture-recapture procedure applied to cases of Alzheimer’s disease, based on two epidemiological surveillance systems. To estimate the total number of patients affected by Alzheimer's disease, a capture-recapture study included a cohort of patients with Alzheimer's disease or receiving medications only eligible for use for this condition, recorded by a specific health insurance information system (Health Insurance Cohort, HIC), and those registered in the French National Alzheimer’s Data Bank (“Banque Nationale Alzheimer”, BNA) in 2010 and 2011. We applied Bayesian estimation of the M_t ecological model, taking into account age and gender as covariates, i.e. factors of inhomogeneous catchability. Overall, 5,562 patients with Alzheimer's disease were recorded, of whom only 856 were common to both information systems. Mean age and F/M sex ratio differed between BNA and HIC surveillance systems, 81 vs 84 years and 2.7 vs 3.2, respectively. A Bayesian estimation, with age and gender as covariates, yields an estimate of 15,060 cases of Alzheimer's disease [95%HPDI: 14,490–15,630] in the Alpes-Maritimes. The completeness of the HIC and BNA databases were respectively of 25.4% and 17.2%. The estimated prevalence rate among the population over 65 years old was 6.3% in 2010–2011. This study demonstrates that it is possible to determine the number of subjects affected by Alzheimer's disease in a geographical unit, using available data from two existing surveillance systems in France, i.e. 15,060 cases in the Alpes-Maritimes. This is the first stage of a population-based approach in view of adapting available resources to the population’s needs.