Abstract Sinergy is the interaction of two or more agents to produce a combined effect greater than the sum of their separate effects. Etherdiamine yields superior results for quartz floatability in a Hallimond tube and higher selectivity in the reverse bench scale cationic flotation of an iron ore, when compared to ethermonoamine. Blending these collectors yields better results than each one used individually characterizing a synergistic effect. This work evaluated the effects of the collectors ethermonoamine, etherdiamine and the mixture of these at the ratio 1:1 on the flotation of the quartz through the microflotation and bench flotation tests with a typical Brazilian iron ore. The results demonstrated the occurrence of synergistic effects in tests performed at concentrations of 1 and 3 mg/L and pH 10.5, in the absence of a depressant. In the presence of a depressant, the synergy was not observed under the same tested conditions, due to the collector-depressant interaction. On other hand, the bench flotation tests indicated the occurrence of synergy regarding silica content in the concentrate while an additive effect was observed for the iron recovery and Selectivity Index index demonstrating that a feasibility of using collector mixtures in this process, was not clearly achieved on the tested ratio 1:1.

RESUMO Objetivo: Identificar características preditivas associadas à evolução da sarcoidose na avaliação inicial e desenvolver um escore preditivo. Métodos: Estudo retrospectivo com pacientes com sarcoidose pulmonar, classificados como tendo evolução autolimitada ou persistente da doença, comparando dados entre os desfechos por meio de análise univariada. Características relacionadas à doença persistente foram selecionadas por meio de análise multivariada, e foi desenvolvido um escore prognóstico. Resultados: A amostra foi composta por 200 pacientes (média de idade = 49 anos). A mediana da duração dos sintomas até o diagnóstico foi de 12 meses, e houve diagnóstico tardio (> 12 meses) em 43% dos casos. O estádio radiológico mais frequente foi o II; 37% apresentavam redução da CVF. Envolvimento sistêmico relevante foi detectado em 37% dos pacientes. Tratamento para tuberculose foi prescrito em 44 pacientes antes do diagnóstico de sarcoidose. Tratamento para sarcoidose foi necessário em 77% da amostra, e a evolução da doença foi persistente em 115 casos. Com a exclusão de 40 pacientes com doença fibrótica, os fatores prognósticos para doença persistente foram comprometimento parenquimatoso, diagnóstico tardio, dispneia, comprometimento sistêmico relevante e redução da CVF. Com base na análise, foi desenvolvido um sistema de pontuação por letras (A, B e C) de acordo com os fatores selecionados. Os valores preditivos positivos para evolução persistente para as pontuações A (≤ 1 ponto) e C (≥ 4 pontos) foram de 12,5% e 81,8%, respectivamente. Conclusões: É possível derivar um escore por meio de características selecionadas na avaliação inicial, permitindo a predição de desfechos em um significativo número de pacientes com sarcoidose.

ABSTRACT Objective: To identify predictive features associated with the course of sarcoidosis at initial evaluation and to develop a predictive score. Methods: This was a retrospective study involving pulmonary sarcoidosis patients, classified as having a self-limited or persistent course of disease, comparing data between the outcomes by univariate analysis. Features related to persistent disease were selected by multivariate analysis and a prognostic score was designed. Results: The sample comprised 200 patients (mean age = 49 years). The median duration of symptoms to diagnosis was 12 months, and delayed diagnosis (> 12 months) was found in 43% of the cases. The most common radiological stage was II; 37% had reduced FVC. Relevant systemic involvement was detected in 37% of the patients. Treatment for tuberculosis was prescribed in 44 patients prior to sarcoidosis diagnosis. Treatment for sarcoidosis was required in 77% of the sample, and the disease course was persistent in 115 cases. Excluding 40 patients with fibrotic disease, prognostic factors to persistent disease were parenchymal involvement, delayed diagnosis, dyspnea, relevant systemic involvement, and reduced FVC. On the basis of the analysis, a 3-letter scoring system (A, B and C) was developed according to the selected factors. The positive predictive values for persistent course for A (≤ 1 point) and C scores (≥ 4 points) were 12.5% and 81.8%, respectively. Conclusions: A score can be derived by selected features at initial evaluation, allowing the prediction of outcomes in a significant number of sarcoidosis patients.

Abstract Low-grade manganese ores that are composed of manganese oxides, wad, quartz, iron oxides, gibbsite, and especially of spessartine (Mn3Al2(SiO4)3) are known as gondite. Spessartine is a mineral with a high content of silica (SiO2) and alumina (Al2O3) that causes a decrease of the enrichment in manganese oxide concentrates by flotation, giving this ore more complexity for processing. Thus, by ensuring a higher selectivity between manganese oxides minerals and silicates, the use of gondite reserves becomes viable, and the correct reagent type can be useful for this objective. Moreover, there are few publications devoted to the study of spessartine in flotation. So, this study investigated the effects of Mn2+ ions on quartz and spessartine depression and showed positive results with the reduction of quartz floatability from 7.06% to 1.23% and the spessartine from 27.30% to 17.12% respectively when the Mn2+ (1000 mg/L) was added previously to the depressant. Zeta potential determinations showed that Mn2+ can act as a silicate activator, possibly by facilitating the SiO(OH)3 - adsorption. Infrared spectroscopy analysis revealed absorption bands at 3,450 cm-1 and 3,400 cm-1 frequency for quartz and spessartine and the adsorption of Mn(OH)2 was responsible for this result.

RESUMO Objetivo: Biomarcadores associados à mucina-1, tais como Krebs von den Lungen-6 e carbohydrate antigen (CA, antígeno carboidrato) 15-3, encontram-se aumentados em diversas doenças pulmonares intersticiais. Nosso objetivo foi determinar se CA 15-3 poderia ser considerado um biomarcador de gravidade de doença em pacientes com pneumonite de hipersensibilidade crônica (PHc). Métodos: Estudo prospectivo observacional envolvendo pacientes adultos com PHc. Os níveis séricos de CA 15-3 foram medidos e correlacionados com variáveis relacionadas à gravidade e extensão da doença. As imagens de TCAR foram analisadas quantitativamente utilizando uma plataforma computacional e uma ferramenta de análise de imagem (Computer-Aided Lung Informatics for Pathology Evaluation and Rating). Os níveis de CA 15-3 foram normalizados por transformação logarítmica. Resultados: A amostra foi composta por 41 pacientes. A média de idade dos pacientes foi de 60,1 ± 11,6 anos. A média da CVF em % do previsto foi de 70,3% ± 17,3%, e a mediana do nível sérico de CA 15-3 foi de 48,1 U/mL. Os níveis de CA 15-3 se correlacionaram inversamente com CVF em % do previsto (r = −0,30; p = 0,05), DLCO em % do previsto (r = −0,54; p < 0,01) e SpO2 ao final de um teste de degrau de 4 minutos (r = −0,59; p < 0,01), mas se correlacionaram diretamente com a pontuação quantitativa total da TCAR (r = 0,47; p = 0,004), especialmente quanto a opacidades em vidro fosco (r = 0,58; p < 0,001). Conclusões: É provável que o CA 15-3 seja um biomarcador de gravidade de doença em pacientes com PHc, particularmente quanto a anormalidades nas trocas gasosas.

ABSTRACT Objective: Biomarkers associated with mucin 1, such as Krebs von den Lungen-6 and carbohydrate antigen (CA) 15-3, are increased in various interstitial lung diseases. Our aim was to determine whether CA 15-3 could be considered a biomarker of disease severity in patients with chronic hypersensitivity pneumonitis (cHP). Methods: This was a prospective observational study involving adult patients with cHP. Serum levels of CA 15-3 were measured and were correlated with variables related to disease severity and extension. HRCT scans were quantitatively analyzed using a computational platform and an image analysis tool (Computer Aided Lung Informatics for Pathology Evaluation and Rating). CA 15-3 levels were normalized by logarithmic transformation. Results: The sample comprised 41 patients. The mean age of the patients was 60.1 ± 11.6 years. The mean FVC in % of predicted was 70.3% ± 17.3%, and the median of the serum level of CA 15-3 was 48.1 U/mL. CA 15-3 levels inversely correlated with FVC in % of predicted (r = −0,30; p = 0,05), DLCO in % of predicted (r = −0,54; p < 0,01), and SpO2 at the end of a 4-min step test (r = −0,59; p < 0,01), but they directly correlated with total quantitative HRCT scores (r = 0,47; p = 0,004), especially regarding ground-glass opacities (r = 0.58; p < 0,001). Conclusions: CA 15-3 is likely to be a biomarker of disease severity of patients with cHP, particularly regarding gas exchange abnormalities.

Abstract Quartz floatability in cationic reverse flotation depends on the suitable choice of surfactant type and the conditions under which they are applied. The design of experiments (DOE) allows the evaluation of process variables, in a structured and independent way, with statistical validation and a limited number of tests. Tests of microflotation of quartz, in the size range -150 +75 µm, using factorial design of experiments, showed that etherdiamine leads to higher level of quartz floatability than ethermonoamine, favored by increase in collector concentration, at the high level of pH tested (11.0). Floatability values above 90% were achieved with the use of 3 mg/L of ether diamine for both pH levels, while with ether monoamine the target was reached only at pH 11.

RESUMO | Descrevemos aqui um caso de uma mulher de 21 anos que apresentou baixa acuidade visual, dor e hiperemia no olho esquerdo por 45 dias. O olho apresentava infiltrado corneano extenso, com fusão e perfuração central colada com cianoacrilato, mas com Seidel (+). Ela foi submetida a transplante de córnea tectônica e lavagem de câmara anterior com infiltração subconjuntival com voriconazol, além de injeções intracamerais de anfoterecina B. Testes laboratoriais revelaram Paecilomyces lilacinus como agente infeccioso. A paciente foi então mantida com voriconazol oral e colírio por período de três meses, após o qual a infecção foi considerada curada. No entanto, no sexto mês de pós-operatório, ela apresentou rejeição endotelial e, duas semanas após, sinais de recidiva de infecção fúngica. Ela foi tratada com mais duas lavagens de câmara anterior e injeção subconjuntival de voriconazol, seguida por voriconazol intravenoso que foi substituído por gotas após 10 dias. A infecção piorou inicialmente, mas depois regrediu e, no último seguimento, o paciente ainda estava livre de infecção.

ABSTRACT | We describe here a case of a 21-year-old woman who presented with low visual acuity, pain, and hyperemia in the left eye for 45 days. Her eye had extensive corneal infiltrate, with melting and a central perforation that was glued with cyanoacrylate, but with Seidel (+). She underwent tectonic corneal transplantation, and anterior chamber lavage with subconjunctival infiltration with voriconazole, as well as intracameral injections of amphotericin B. Laboratory tests revealed Paecilomyces lilacinus as the infectious agent. The patient was then maintained with oral voriconazole and eye drops for three months, after which the infection was considered cured. However, in the sixth postoperative month she presented with endothelial rejection, and two weeks later signs of recurrence of the fungal infection. She was treated with two further washes of the anterior chamber and subconjunctival injection of voriconazole, followed by intravenous voriconazole that was replaced with drops after ten days. The infection initially worsened, but then regressed, and at last follow-up, the patient was still infection-free.

RESUMO Objetivo Derivar valores de referência em adultos brancos para a difusão do monóxido de carbono (DCO) em uma amostra de diferentes locais do Brasil por um mesmo modelo de equipamento (Sensormedics) e comparar os resultados com os derivados pelas equações de Crapo, Miller e Neder, e da proposta pelo Global Lung Initiative (GLI). Métodos Os testes foram realizados de acordo com as normas sugeridas pela ATS/ERS, em 2005, em seis cidades brasileiras, em 120 voluntários adultos de cada sexo, não fumantes, sem anemia referida e sem doenças pulmonares ou cardíacas. Os previstos foram derivados por regressões lineares e as diferenças entre os valores previstos por alguns autores e os observados no estudo atual foram calculadas. Resultados Nos homens, a idade variou de 25 a 88 anos e a estatura, de 156 a 189 cm. Nas mulheres, a idade variou de 21 a 92 anos e a estatura, de 140 a 176 cm. A DCO se correlacionou de maneira significativa positivamente com a estatura e negativamente com a idade. Os valores previstos pelas equações de Crapo, Neder e Miller foram maiores em comparação aos obtidos pelo estudo atual (p<0,01) em ambos os sexos. Nos homens, os valores não diferiram quando comparados aos calculados pelo GLI (p=0,29); nas mulheres, os valores derivados pelo GLI foram levemente maiores: 0,99 mL/min/mmHg (p<0,01). Conclusões Novos valores previstos para a DCO foram derivados em uma amostra de adultos brancos no Brasil. Os valores previstos são semelhantes aos compilados pelas equações GLI e diferem de equações propostas anteriormente.

ABSTRACT Objective To derive reference values from white race adults, for DCO in a sample from different sites in Brazil, through the same equipment model (Sensormedics), and compare the results with the derivatives from Crapo, Miller, Neder equations and from the Global Lung Initiative (GLI) proposal. Methods The tests were performed according to the norms suggested by ATS/ERS in 2005 in six Brazilian cities, with 120 adult volunteers of each gender, non-smokers, without referred anemia and without lung or cardio diseases. The expected values were derived from linear regressions and the differences between the values forecasted by some authors and the ones observed in the current study were calculated. Results Among men, the age varied between 25 and 88 years old, and the height varied between 140 and 176 cm. DCO was correlated significantly and positively with the height and negatively with the age. The values forecasted by Crapo, Neder, and Miller equations were higher in comparison with the ones obtained by the current study (p<0.01) in both genders. Among men, the values did not differ when compared to the ones calculated by GLI (p=0.29); among women, the values derived by GLI were slightly higher: 0.99 ml/min/mmHg (p<0.01). Conclusion new values forecasted for DCO were derived in a sample of white adults in Brazil. The forecasted values are similar to the ones complied by GLI equations and differ from the previously proposed equations.

RESUMO Objetivo Ensaios clínicos mostraram que 150 mg de Nintedanibe duas vezes ao dia reduzem a progressão da doença em pacientes com Fibrose Pulmonar Idiopática (FPI), com um perfil de efeitos adversos que é controlável para a maioria dos pacientes. Antes da aprovação do Nintedanibe como tratamento para a FPI no Brasil, um Programa de Acesso Expandido (PEA) foi iniciado para fornecer acesso precoce ao tratamento e avaliar a segurança e a tolerância do Nintedanibe para este grupo de pacientes. Métodos Foram elegíveis para participar da PEA pacientes com diagnóstico de FPI nos últimos 5 anos, com capacidade vital forçada (CVF) ≥ 50% do previsto e capacidade de difusão dos pulmões para monóxido de carbono (DLco) 30%-79% do previsto. Os pacientes receberam Nintedanibe 150 mg, 2 vezes ao dia (bid). As avaliações de segurança incluíram eventos adversos que levaram à suspensão permanente do Nintedanibe e eventos adversos graves. Resultados O PEA envolveu 57 pacientes em 8 centros. A maioria dos pacientes era do sexo masculino (77,2%) e brancos (87,7%). No início do estudo, a média de idade foi de 70,7 (7,5) anos e a CVF foi de 70,7 (12,5%) do previsto. A média de exposição ao Nintedanibe foi de 14,4 (6,2) meses; a exposição máxima foi de 22,0 meses. Os eventos adversos frequentemente relatados pelo pesquisador como relacionados ao tratamento com Nintedanibe foram diarreia (45 pacientes, 78,9%) e náusea (25 pacientes, 43,9%). Os eventos adversos levaram à suspensão permanente do Nintedanibe em 16 pacientes (28,1%) que passaram por um evento adverso grave. Conclusões No PEA brasileiro, o Nintedanibe apresentou um perfil aceitável de segurança e tolerância em pacientes com FPI, condizendo com dados de ensaios clínicos.

ABSTRACT Objective Clinical trials have shown that nintedanib 150 mg twice daily (bid) reduces disease progression in patients with idiopathic pulmonary fibrosis (IPF), with an adverse event profile that is manageable for most patients. Prior to the approval of nintedanib as a treatment for IPF in Brazil, an expanded access program (EAP) was initiated to provide early access to treatment and to evaluate the safety and tolerability of nintedanib in this patient population. Methods Patients with a diagnosis of IPF within the previous five years, forced vital capacity (FVC) ≥ 50% predicted and diffusing capacity of the lungs for carbon monoxide (DLco) 30% to 79% predicted were eligible to participate in the EAP. Patients received nintedanib 150 mg bid open-label. Safety assessments included adverse events leading to permanent discontinuation of nintedanib and serious adverse events. Results The EAP involved 57 patients at eight centers. Most patients were male (77.2%) and white (87.7%). At baseline, mean (SD) age was 70.7 (7.5) years and FVC was 70.7 (12.5) % predicted. Mean (SD) exposure to nintedanib was 14.4 (6.2) months; maximum exposure was 22.0 months. The most frequently reported adverse events considered by the investigator to be related to nintedanib treatment were diarrhea (45 patients, 78.9%) and nausea (25 patients, 43.9%). Adverse events led to permanent discontinuation of nintedanib in 16 patients (28.1%). Sixteen patients (28.1%) had a serious adverse event. Conclusion In the Brazilian EAP, nintedanib had an acceptable safety and tolerability profile in patients with IPF, consistent with data from clinical trials.

The aim of this study was to estimate the prevalence of low-back pain (LBP) and to identify the level of functional disability in elderly individuals in different populations. From January 1985 to October 2018, a search was performed using the following databases: Embase, LILACS, SciELO, Scopus, Medline, and the Web of Science. The descriptors were low-back pain, back pain, lower-back pain, prevalence, and elderly in Portuguese and English. Two independent reviewers conducted a search for studies and evaluated their methodological quality. The search strategy returned 2186 titles, and 35 were included in this review. The studies evaluated 135,059 elderly individuals aged between 60 and 102 years, and the prevalence of LBP ranged from 21% to 75%. The levels of functional disability, as well as functional difficulties, activities of daily living, and physical capacity, were identified in 60% of the studies. This review indicated a high prevalence of LBP in elderly individuals and functional disability that affects factors important for independence. However, the studies used different methodologies, suggesting that more studies be conducted with scientific accuracy, methodological quality, and low risk of bias to contribute to the proposal of preventive actions for elderly populations.

RESUMO Objetivo: Derivar valores de referência para brasileiros adultos brancos saudáveis que nunca fumaram e comparar os valores obtidos com os valores de referência derivados por Crapo e por Neder. Métodos: Equações de referência por regressões quantílicas foram derivadas em 122 homens e 122 mulheres, não obesos, em sete cidades do Brasil. A idade variou entre 21 e 92 anos nas mulheres e de 25 a 88 anos nos homens. Os volumes pulmonares foram medidos por pletismógrafo de corpo automatizados SensorMedics, de acordo com as recomendações da SBPT e ATS/ERS. Os limites inferior e superior, expressos pelo percentil 5 e 95, foram derivados por equações específicas. Os resultados foram comparados aos sugeridos por Crapo em 1982 e Neder em 1999. Resultados: Os valores medianos para a capacidade pulmonar total (CPT) foram influenciados apenas pela estatura nos homens, e pela estatura e idade nas mulheres. O volume residual foi influenciado pela idade e estatura em ambos os sexos. O peso se correlacionou diretamente com a capacidade inspiratória e inversamente com a capacidade residual funcional e com o volume de reserva expiratório em ambos os sexos. A CPT observada, comparada com os valores previstos pela equação de Neder, foi significativamente menor. Os valores médios foram semelhantes entre os dados do presente estudo e os de Crapo. Conclusões: Novos valores previstos para os volumes pulmonares foram obtidos em uma amostra de brasileiros de raça branca. Os valores diferem daqueles derivados por Neder, mas são semelhantes aos derivados por Crapo.

ABSTRACT Objective: To derive reference values for healthy white Brazilian adults who have never smoked and to compare the obtained values with reference values derived by Crapo and by Neder. Methods: Reference equations by quantile regressions were derived in 122 men and 122 women, non-obese, living in seven cities in Brazil. Age ranged from 21 to 92 years in women and from 25 to 88 years in men. Lung function tests were performed using SensorMedics automated body plethysmographies according ATS/ERS recommendations. Lower and upper limits were derived by specific equations for 5 and 95 percentiles. The results were compared to those suggested by Crapo in 1982, and Neder in 1999. Results: Median values for total lung capacity (TLC) were influenced only by stature in men, and by stature and age in women. Residual volume was influenced by age and stature in both genders. Weight was directly related to inspiratory capacity and inversely with functional residual capacity and expiratory reserve volume in both genders. A comparison of observed TLC data with values predicted by Neder equations showed significant lower values by the present data. Mean values were similar between data from present study and those derived by Crapo. Conclusion: New predicted values for lung volumes were obtained in a sample of white Brazilians. The values differ from those derived by Neder, but are similar to those derived by Crapo.

RESUMO Objetivo: Derivar equações de referência para a espirometria forçada em adultos brasileiros negros, saudáveis, que nunca fumaram, e comparar os resultados com os valores previstos para a raça branca publicados em 2007. Métodos: Os exames seguiram as normas recomendadas pela Sociedade Brasileira de Pneumologia e Tisiologia, e os espirômetros preencheram os requisitos técnicos exigidos pelas diretrizes da American Thoracic Society/European Respiratory Society. Os limites inferiores foram derivados pela análise do 5º percentil dos resíduos. Resultados: Equações e limites de referência foram derivados de uma amostra com 120 homens e 124 mulheres, habitantes de oito cidades brasileiras, utilizando-se um espirômetro de fluxo. Os valores previstos para CVF, VEF1, relação VEF1/CVF e PFE foram mais bem ajustados por regressões lineares, enquanto os fluxos, por equações logarítmicas. Os valores de referência de VEF1 e CVF para ambos os sexos foram significativamente menores quando comparados aos previstos para adultos da raça branca no Brasil. Conclusões: O fato de que os valores previstos da espirometria forçada derivados para a população negra no Brasil tenham sido inferiores aos previstos para a raça branca no país justifica a utilização de uma equação específica para adultos negros.

ABSTRACT Objective: To derive reference equations for spirometry in healthy Black adult never smokers in Brazil, comparing them with those published in 2007 for White adults in the country. Methods: The examinations followed the standards recommended by the Brazilian Thoracic Association, and the spirometers employed met the technical requirements set forth in the guidelines of the American Thoracic Society/European Respiratory Society. The lower limits were defined as the 5th percentile of the residuals. Results: Reference equations and limits were derived from a sample of 120 men and 124 women, inhabitants of eight Brazilian cities, all of whom were evaluated with a flow spirometer. The predicted values for FVC, FEV1, FEV1/FVC ratio, and PEF were better described by linear equations, whereas the flows were better described by logarithmic equations. The FEV1 and FVC reference values derived for Black adults were significantly lower than were those previously derived for White adults, regardless of gender. Conclusions: The fact that the predicted spirometry values derived for the population of Black adults in Brazil were lower than those previously derived for White adults in the country justifies the use of an equation specific to the former population.

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.

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.