Prevalence of Covid-19 sequelae in the National Health and Nutrition Survey 2020 / Secuelas de Covid-19: Encuesta Nacional de Salud y Nutrición 2020

Abstract: Objective: To estimate the prevalence of Covid-19 sequelae and its association with sociodemographic and medical care characteristics. Materials and methods: Mexican adults that experienced Covid-19 symptoms and were seropositive to the N-protein of Sars-CoV-2 in the Ensanut 2020 responded to a question regarding sequelae. Associations were estimated using Poisson regression. Results: The prevalence of sequelae was 15.7%, being higher for people with higher education and who were hospitalized or treated at an emergency room during the acute Covid-19 phase. Conclusions: Self-reported sequelae associated to Covid-19 was frequent. Covid-19 sequelae could represent an important challenge for the health system and the Mexican society.

Resumen: Objetivo: Estimar la prevalencia de secuelas para Covid-19 y su asociación con características sociodemográficas y de atención médica. Material y métodos: Adultos mexicanos que experimentaron síntomas de Covid-19 y fueron seropositivos a la proteina N del SARS-CoV-2 respondieron una pregunta sobre secuelas. Se estimaron las asociaciones mediante regresión Poisson. Resultados: La prevalencia de secuelas fue de 15.7%, siendo mayor en personas con alto nivel educativo y que recibieron atención hospitalaria o de urgencia durante la fase aguda de Covid-19. Conclusiones: El autorreporte de secuelas asociadas con Covid-19 fue frecuente. Las secuelas por Covid-19 podrían representar un reto importante para el sistema de salud y la sociedad mexicana.

Effect of the Standardization of Diagnostic Tests on the Prevalence of Diabetes Mellitus and Impaired Fasting Glucose

BACKGROUND: Without standardization of medical laboratory's testing practices, there is an increase in false diagnoses when relying on test results. However, the effect of test standardization is difficult to assess numerically. This study's purpose is to quantify the effect of the standardization level of a laboratory on the prevalence of diabetes mellitus (DM) and impaired fasting glucose (IFG). METHODS: Laboratories were classified into three levels: ‘highly-standardized laboratory,’‘basically-standardized laboratory,’ and ‘non-standardized laboratory.’ Based on the results of Korean External Quality Assessment Scheme (KEQAS), the cutoff values for diagnosis of DM and IFG were recalculated, given false positive and false negative rates. RESULTS: The prevalence of DM and IFG in the population as a whole was estimated using the 2013 Korea National Health and Nutrition Examination Survey (KNHANES) database. When the prevalence of DM from KNHANES was 11.88% (95% confidence interval [CI], 10.59%–13.17%), the proportion with a systematic false error ranged from 10.91% (95% CI, 9.65%–12.17%) to 13.09% (95% CI, 11.74%–14.45%). The prevalence of IFG varied from 13.59% (95% CI, 12.25%–14.91%) to 40.49% (95% CI, 38.54%–42.43%), in contrast to 24.58% (95% CI, 22.85%–26.31%) of the reference value. The prevalence of DM and IFG tended to be over- and under-estimated more as the laboratory standardization level became lower, respectively. CONCLUSION: Our study proved that standardization of clinical laboratory tests is an important factor affecting the prevalence estimation of national disease statistics based on the simulation using KNHANES data.

Comparison of the Prevalence of Chronic Obstructive Pulmonary Disease Diagnosed by Lower Limit of Normal and Fixed Ratio Criteria

The Global Initiative of Chronic Obstructive Lung Disease (GOLD) guidelines define chronic obstructive pulmonary disease (COPD) in subjects with FEV1/FVC or =65, 14.9% and 31.1%, respectively. In conclusion, the prevalence of COPD by LLN criterion was significantly lower in elderly compared to fixed ratio of FEV1/FVC. Implementing LLN criterion instead of fixed ratio of FEV1/FVC may reduce the risk of over-diagnosis of COPD in elderly people.