Intérêt d'une approche géostatistique pour analyser les disparités géographiques de la couverture vaccinale contre les papillomavirus humains en France

International audienceBackground: The use of geostatistical methods remains rare in health studies. In order to assess the usefulness of the geostatistical approach in epidemiology, we chose to apply these methods to the vaccination coverage rate (VCR) against human papillomavirus (HPV) in France. Indeed, HPV vaccine coverage remains low in France and geographical disparities are sizable. The objective of this study was to identify the socioecological factors that may explain these geographical variations. Methods: Sociological, economic and behavioral data for 2016 have been gathered (demographics and public health database, web and social networks) and were correlated with the HPV VCR vaccine coverage over the French territory. Homogeneous geographical areas defined by strong correlations for groups of variables were selected. In each homogeneous area, principal component analysis was performed and a geostatistical approach provided an estimate predicting vaccine coverage at a given scale. Results: HPV VCR spatial variations in France cannot be fully explained by a single model. In urban areas, a low rate of HPV VCR is preferentially associated with unfavorable socioeconomic factors (poverty, unemployment, immigration). In rural areas, HPV VCR is preferentially associated with sociocultural factors (socio-professional categories, education level, interest in alternative medicines the anti-vaccine movement). Two secondary geographical areas were defined: the Île-de-France region and 12 departments in northeastern France. In the Île-de-France region, the association with the economic factors one again appears as in urban areas in general. The northeasteran departments represent a particular case insofar as HPV VCR is relatively high, notwithstanding economic poverty indicators. Conclusion: Geostatistical modeling successfully identifies new potential explanations for HPV VCR geographical disparities in France. These results could help to adapt or develop future vaccination programs in specific areas by taking into account the sociological, economic and behavioral characteristics of their populatio

What Is the Best Treatment of Locally Advanced Nasopharyngeal Carcinoma? An Individual Patient Data Network Meta-Analysis.

Purpose The role of adjuvant chemotherapy (AC) or induction chemotherapy (IC) in the treatment of locally advanced nasopharyngeal carcinoma is controversial. The individual patient data from the Meta-Analysis of Chemotherapy in Nasopharynx Carcinoma database were used to compare all available treatments. Methods All randomized trials of radiotherapy (RT) with or without chemotherapy in nonmetastatic nasopharyngeal carcinoma were considered. Overall, 20 trials and 5,144 patients were included. Treatments were grouped into seven categories: RT alone (RT), IC followed by RT (IC-RT), RT followed by AC (RT-AC), IC followed by RT followed by AC (IC-RT-AC), concomitant chemoradiotherapy (CRT), IC followed by CRT (IC-CRT), and CRT followed by AC (CRT-AC). P-score was used to rank the treatments. Fixed- and random-effects frequentist network meta-analysis models were applied. Results The three treatments with the highest probability of benefit on overall survival (OS) were CRT-AC, followed by CRT and IC-CRT, with respective hazard ratios (HRs [95% CIs]) compared with RT alone of 0.65 (0.56 to 0.75), 0.77 (0.64 to 0.92), and 0.81 (0.63 to 1.04). HRs (95% CIs) of CRT-AC compared with CRT for OS, progression-free survival (PFS), locoregional control, and distant control (DC) were, respectively, 0.85 (0.68 to 1.05), 0.81 (0.66 to 0.98), 0.70 (0.48 to 1.02), and 0.87 (0.61 to 1.25). IC-CRT ranked second for PFS and the best for DC. CRT never ranked first. HRs of CRT compared with IC-CRT for OS, PFS, locoregional control, and DC were, respectively, 0.95 (0.72 to 1.25), 1.13 (0.88 to 1.46), 1.05 (0.70 to 1.59), and 1.55 (0.94 to 2.56). Regimens with more chemotherapy were associated with increased risk of acute toxicity. Conclusion The addition of AC to CRT achieved the highest survival benefit and consistent improvement for all end points. The addition of IC to CRT achieved the highest effect on DC