Aproximación a la incidencia real de tuberculosis en el Área de Salud de León: aplicación del método captura-recaptura para comparar 2 fuentes de información / Estimate of the real incidence of tuberculosis in the Leon Health Area: Application of the capture-recapture method to compare two information sources

Introducción: La incidencia real de la tuberculosis podría ser mayor que la recogida en registros tanto nacionales como internacionales. Se estima una infradeclaración que varía entre un 7 y un 27% según los estudios. Objetivo Analizar la tasa de incidencia de tuberculosis en el Área de Salud de León comparando 2 fuentes de información: consumo de tuberculostáticos (asociación isoniacida-rifampicina) y registro del Sistema de Información de Vigilancia Epidemiológica de Castilla y León (SIVE).Método Estudio descriptivo retrospectivo en un área de salud de 351.086 habitantes durante los años 2008 y 2009. Fueron recogidas 2 fuentes de información: consumo de tuberculostáticos y registro SIVE. Se calcularon las tasas de incidencia para cada fuente y posteriormente se aplicó el método captura-recaptura. Se analizaron las características epidemiológicas como datos demográficos, clínicos, diagnósticos, tratamiento y seguimiento. Resultados La incidencia obtenida para 2008 según el SIVE fue de 18,80 × 100.000 habitantes y según el registro de farmacia de 26,77. En 2009, según el SIVE, fue de 18,23 × 100.000 habitantes y según farmacia 22,50. Cuando se aplicó el método captura-recaptura, la incidencia anual para 2008 fue de 44,14 × 100.000 (IC 95%: 37,88-50,41) y para 2009 de 34,17 (IC 95%: 30,19-38,17). En cada uno de los años estudiados el número de casos obtenidos en el registro de farmacia fue mayor que en el SIVE. Conclusiones Los datos del SIVE sobre la incidencia de tuberculosis en el Área de Salud de León infraestiman la tasa de incidencia real. La fuente de información que supone el registro de consumo de tuberculostáticos de la comunidad está infrautilizada. El método de captura-recaptura constituye una buena alternativa para medir incidencias y exhaustividad de los sistemas de vigilancia (AU)

Introduction: The actual incidence of tuberculosis is probably higher than that previously published in national and international records. Under-reporting is estimated to fluctuate between 7% and 27%,according to studies. Objective: To estimate the incidence rate of tuberculosis in the area of León for 2008 and 2009 using the capture-recapture method in order to compare two sources of information: prescribed tuberculostatic drugs (combination of rifampicin-isoniazid) and the regional epidemiological surveillance system register (SIVE).Method: Retrospective descriptive study in an area of 351,086 inhabitants of tuberculosis cases using assources: (i), information on prescribed tuberculostatic drugs, and (ii), the SIVE register. We calculated incidence rates for each source by the capture-recapture method. We analyzed epidemiological and demographic data, symptoms, diagnosis, treatment and follow-up. Results: The incidence based on the SIVE data for 2008 was 18.80/100,000 inhabitants and according to the pharmacy register, the rate was 26.77. The estimated value for 2009 based on the SIVE data was 18.23/100,000 inhabitants, and according to the pharmacy register, it was 22.50. After applying the capture-recapture method, the annual incidence for 2008 was 44.14/100,000 (95% CI; 37.88-50.41) and for 2009, it was 34.17/100,000 (95% CI; 30.19-38.17). In the study of all these years we have found that the number of cases were higher in the pharmacy register than the SIVE one. Conclusions: The SIVE data on the incidence of tuberculosis in our study area underestimates the actual incidence rate. The source of information that involves case record of tuberculosis in the community is under-used. The capture-recapture method is a good alternative to measure the incidence of tuberculosis, and to check the surveillance systems (AU)

[Estimate of the real incidence of tuberculosis in the Leon Health Area: application of the capture-recapture method to compare two information sources]. / Aproximación a la incidencia real de tuberculosis en el Área de Salud de León: aplicación del método captura-recaptura para comparar 2 fuentes de información.

INTRODUCTION: The actual incidence of tuberculosis is probably higher than that previously published in national and international records. Under-reporting is estimated to fluctuate between 7% and 27%, according to studies. OBJECTIVE: To estimate the incidence rate of tuberculosis in the area of León for 2008 and 2009 using the capture-recapture method in order to compare two sources of information: prescribed tuberculostatic drugs (combination of rifampicin-isoniazid) and the regional epidemiological surveillance system register (SIVE). METHOD: Retrospective descriptive study in an area of 351,086 inhabitants of tuberculosis cases using as sources: (i), information on prescribed tuberculostatic drugs, and (ii), the SIVE register. We calculated incidence rates for each source by the capture-recapture method. We analyzed epidemiological and demographic data, symptoms, diagnosis, treatment and follow-up. RESULTS: The incidence based on the SIVE data for 2008 was 18.80/100,000 inhabitants and according to the pharmacy register, the rate was 26.77. The estimated value for 2009 based on the SIVE data was 18.23/100,000 inhabitants, and according to the pharmacy register, it was 22.50. After applying the capture-recapture method, the annual incidence for 2008 was 44.14/100,000 (95% CI; 37.88-50.41) and for 2009, it was 34.17/100,000 (95% CI; 30.19-38.17). In the study of all these years we have found that the number of cases were higher in the pharmacy register than the SIVE one. CONCLUSIONS: The SIVE data on the incidence of tuberculosis in our study area underestimates the actual incidence rate. The source of information that involves case record of tuberculosis in the community is under-used. The capture-recapture method is a good alternative to measure the incidence of tuberculosis, and to check the surveillance systems.