Exacerbaciones agudas en pacientes con fibrosis pulmonar idiopática / Acute exacerbations in patients with idiopathic pulmonary fibrosis

Clásicamente entendemos como exacerbación de la Fibrosis pulmonar idiopática (FPI) a un deterioro respiratorio, clínicamente significativo, sin causa evidente. En la actualidad se prefiere el concepto de "exacerbación aguda gatillada" para referirnos a aquella que se genera en el contexto de infección, aspiración, toxicidad por drogas, tromboembolismo pulmonar, insuficiencia cardiaca o posterior a procedimientos invasivos. Mientras que se reserva el termino de "exacerbación aguda idiopática" a aquella en la que no encontramos un gatillante. El pronóstico es ominoso, con mortalidad elevada, con cifras que fluctúan entre 50-90% dependiendo de la necesidad de soporte ventilatorio. Por lo que muchas veces una exacerbación aguda puede ser el evento final de un paciente con FPI. El tratamiento no es del todo claro, no existe evidencia robusta del beneficio de terapias, históricamente los corticoides se han utilizados como terapia estándar, sin embargo la evidencia actual cuestiona los beneficios de dicho tratamiento.

Classically we understand as an exacerbation of Idiopathic Pulmonary Fibrosis (IPF) to a clinically significant respiratory deterioration, without obvious cause. At present, the concept of "acute triggered exacerbations" is preferred to refer to those that are generated in the context of infection, aspiration, drug toxicity, pulmonary thromboembolism, heart failure or after invasive procedures. While the term "idiopathic acute exacerbations" is reserved for those in which we do not find a trigger. The prognosis is ominous and the mortality is high, with figures that fluctuate between 50 to 90% depending on the need for ventilatory support. Many times an acute exacerbation can be the final event of a patient with IPF. The treatment is not entirely clear, there is no robust evidence of the benefit of therapies, historically corticosteroids have been used as standard therapy, however current evidence questions the benefits of such a treatment.

Six-minute walk distance and survival time in patients with idiopathic pulmonary fibrosis in Brazil / Distância no teste de caminhada de seis minutos e sobrevida na fibrose pulmonar idiopática no Brasil

ABSTRACT Objective: To determine the cut-off point for the six-minute walk distance (6MWD) that indicates lower survival time in patients with idiopathic pulmonary fibrosis (IPF) in Brazil. Methods: This was retrospective study carried out in two referral centers for IPF. The 6MWT was performed twice, considering the highest value of the 6MWD. Various cut-off points were estimated, in absolute values and in percentage of predicted values, using ROC curves, the Kaplan-Meier method, and data from other studies. Results: The sample comprised 70 patients with IPF. The mean age was 71.9 ± 6.4 years, and 50 patients (71.4%) were male. The mean FVC was 76.6 ± 18.2% of predicted value. The mean SpO2 at rest before and after 6MWT were 93.8 ± 2.5% and 85.3 ± 6.5%, respectively. The median survival time was 44 months (95% CI: 37-51 months). The mean 6MWD was 381 ± 115 m (79.2 ± 24.0% of predicted). After the analyses, the best cut-off points for estimating survival were 6MWD < 330 m and < 70% of predicted. The median survival time of patients with a 6MWD < 330 m was 24 months (95% CI: 3-45 months), whereas that of those with a 6MWD ≥ 330 m was 59 months (95% CI: 41-77 months; p = 0.009). Similarly, the median survival times of those with a 6MWD < 70% and ≥ 70% of predicted, respectively, were 24 months (95% CI: 13-35 months) and 59 months (95% CI: 38-80 months; p = 0.013). Cox multivariate regression models including age, sex, smoking status, SpO2 at the end of the 6MWT, and FVC% showed that 6MWD remained significantly associated with survival (p = 0.003). Conclusions: Values of 6MWD < 330 m and < 70% of predicted value were associated with lower survival time in IPF patients in Brazil.

RESUMO Objetivo: Determinar o ponto de corte da distância no teste de caminhada de seis minutos (DTC6) em relação à menor sobrevida em pacientes com fibrose pulmonar idiopática (FPI) no Brasil. Métodos: Estudo retrospectivo realizado em dois centros de referência para FPI. O TC6 foi realizado em duplicata, considerando-se o maior valor da DTC6. Vários pontos de corte foram estimados, em valores absolutos e em percentual do previsto, utilizando curvas ROC, método de Kaplan-Meier e dados de outros estudos. Resultados: A amostra envolveu 70 pacientes com FPI, com média de idade de 71,9 ± 6.4 anos, sendo 50 homens (71,4%). A média de CVF foi de 76,6 ± 18.2% do previsto. As médias de SpO2 em repouso antes e depois do TC6 foram de 93,8 ± 2,5% e 85,3 ± 6,5%, respectivamente. A mediana de sobrevida foi de 44 meses (IC95%: 37-51 meses). A média da DTC6 foi 381 ± 115 m (79,2 ± 24,0% do previsto). Após as análises, os melhores pontos de corte para estimar a sobrevida foram de DTC6 < 330 m e < 70% do previsto. A mediana de sobrevida foi de 24 meses (IC95%: 3-45 meses) para aqueles com DTC6 < 330 m comparada a 59 meses (IC95%: 41-77 meses) para aqueles com DTC6 ≥ 330 m (p = 0,009). Similarmente, a mediana de sobrevida foi de 24 meses (IC95%: 13-35 meses) para pacientes com DTC6 < 70% do previsto e de 59 meses (IC95%: 38-80 meses) para aqueles com DTC6 ≥ 70% do previsto (p = 0,013). Modelos de regressão multivariada de Cox incluindo idade, sexo, tabagismo, SpO2 ao final do TC6 e CVF% mostraram que a DTC6 permaneceu significativamente associada à sobrevida (p = 0,003). Conclusões: Valores de DTC6 < 330 m e < 70% do valor previsto associaram-se à menor sobrevida em pacientes com FPI no Brasil.