Epidemiological characteristics and outcomes of COVID-19 cases: mortality inequalities by socio-economic status, Barcelona, Spain, 24 February to 4 May 2020

Politi, Julieta; Martín-Sánchez, Mario; Mercuriali, Lilas; Borras-Bermejo, Blanca; Lopez-Contreras, Joaquín; Vilella, Anna; Villar, Judit; Orcau, Angels; de Olalla, Patricia Garcia; Rius, Cristina; de Andres, Anna; Alamo-Junquera, Dolores; Gallego, Carmen; G Abiétar, Daniel; Guillaumes, Montse; Millet, Joan P; Molinero, Emilia; Pérez León, Daniela; Rodríguez, Raquel; Ros, Miriam; Antón, Andrés; Martínez-Gómez, Xavier; Pumarola, Tomás; Campins, Magda; Pomar, Virginia; Navarro, Ferran; Puig, Teresa; Blazquez, Marta; Soriano, Inmaculada; Barón, Lourdes; Marín, Clara; de la Torre, Laura; Castells, Xavier; Posso, Margarita; Horcajada, Juan P; Và rez, Maria A; Sentís, Laia; Gómez, Miquel; Invernon, Leonor; Padilla, Eduardo; Karaim, Mara; Bordon, Noel; Fatjò, Francesc; Berbel, Cristina; González-Nieto, Isabel; González, José L; Pelegrín, Iván; Bargalló, Eva; Salas, Antoni; Planes, Maria C; García, Gloria; de Mendoza, Diego; Tortajada, Sònia; Juan, Natà lia; Casabon, Jordi

BACKGROUND: Population-based studies characterising outcomes of COVID-19 in European settings are limited, and effects of socio-economic status (SES) on outcomes have not been widely investigated. AIM: We describe the epidemiological characteristics of COVID-19 cases, highlighting incidence and mortality rate differences across SES during the first wave in Barcelona, Catalonia, Spain. METHODS: This population-based study reports individual-level data of laboratory-confirmed COVID-19 cases diagnosed from 24 February to 4 May 2020, notified to the Public Health Agency of Barcelona and followed until 15 June 2020. We analysed end-of-study vital status and the effects of chronic conditions on mortality using logistic regression. Geocoded addresses were linked to basic health area SES data, estimated using the composed socio-economic index. We estimated age-standardised incidence, hospitalisation, and mortality rates by SES. RESULTS: Of 15,554 COVID-19-confirmed cases, the majority were women (n = 9,028; 58%), median age was 63 years (interquartile range: 46–83), 8,046 (54%) required hospitalisation, and 2,287 (15%) cases died. Prevalence of chronic conditions varied across SES, and multiple chronic conditions increased risk of death (≥ 3, adjusted odds ratio: 2.3). Age-standardised rates (incidence, hospitalisation, mortality) were highest in the most deprived SES quartile (incidence: 1,011 (95% confidence interval (CI): 975–1,047); hospitalisation: 619 (95% CI: 591–648); mortality: 150 (95% CI: 136–165)) and lowest in the most affluent (incidence: 784 (95% CI: 759–809); hospitalisation: 400 (95% CI: 382–418); mortality: 121 (95% CI: 112–131)). CONCLUSIONS: COVID-19 outcomes varied markedly across SES, underscoring the need to implement effective preventive strategies for vulnerable populations.