Mechanisms of exercise limitation in patients with chronic hypersensitivity pneumonitis

Small airway and interstitial pulmonary involvements are prominent in chronic hypersensitivity pneumonitis (cHP). However, their roles on exercise limitation and the relationship with functional lung tests have not been studied in detail. Our aim was to evaluate exercise performance and its determinants in cHP. We evaluated maximal cardiopulmonary exercise testing performance in 28 cHP patients (forced vital capacity 57±17% pred) and 18 healthy controls during cycling. Patients had reduced exercise performance with lower peak oxygen production (16.6 (12.3-19.98) mL·kg-1·min-1versus 25.1 (16.9-32.0), p=0.003), diminished breathing reserve (% maximal voluntary ventilation) (12 (6.4-34.8)% versus 41 (32.7-50.8)%, p<0.001) and hyperventilation (minute ventilation/carbon dioxide production slope 37±5 versus 31±4, p<0.001). All patients presented oxygen desaturation and augmented Borg dyspnoea scores (8 (5-10) versus 4 (1-7), p=0.004). The prevalence of dynamic hyperinflation was found in only 18% of patients. When comparing cHP patients with normal and low peak oxygen production (<84% pred, lower limit of normal), the latter exhibited a higher minute ventilation/carbon dioxide production slope (39±5.0 versus 34±3.6, p=0.004), lower tidal volume (0.84 (0.78-0.90) L versus 1.15 (0.97-1.67) L, p=0.002), and poorer physical functioning score on the Short form-36 health survey. Receiver operating characteristic curve analysis showed that reduced lung volumes (forced vital capacity %, total lung capacity % and diffusing capacity of the lung for carbon dioxide %) were high predictors of poor exercise capacity. Reduced exercise capacity was prevalent in patients because of ventilatory limitation and not due to dynamic hyperinflation. Reduced lung volumes were reliable predictors of lower performance during exercise

Evaluation of small airway involvement in patients with chronic hypersensitivity pneumonitis and its impact on exercise limitation

INTRODUÇÃO: A pneumonite de hipersensibilidade (PH) é uma doença intersticial causada pela inalação de antígenos orgânicos específicos ou substâncias de baixo peso molecular em indivíduos geneticamente suscetíveis. A PH crônica representa seu estágio final, na qual a exposição antigênica prolongada leva à fibrose. Na PH crônica, o envolvimento das pequenas vias aéreas (PVA) é proeminente; entretanto, uma avaliação detalhada através de métodos funcionais e de avaliação quantitativa e automatizada pela tomografia computadorizada (TC) não foi realizada previamente. MÉTODOS: estudo transversal de 28 pacientes com PH crônica, com avaliação através de provas de função pulmonar (PFPs); oscilometria forçada (FOT); análise automatizada do volume pulmonar através da TC, incluindo quantificação de aprisionamento aéreo; e teste cardiopulmonar de exercício (TCPE) incremental em cicloergômetro para avaliar performance ao exercício, incluindo medidas seriadas da capacidade inspiratória e hiperinsuflação dinâmica (HD). Foram incluídos pacientes entre 18 a 75 anos, com diagnóstico confirmado pela combinação de achados tomográficos, exposição antigênica e biópsia compatível e/ou LBA com linfocitose. Foram excluídos pacientes com CVF e/ou VEF1 20 anos-maço, uso de oxigênio suplementar; diagnóstico prévio de asma ou DPOC, diagnóstico de hipertensão arterial pulmonar ou impossibilidade de realizar TCPE. Os dados foram comparados com controles saudáveis. RESULTADOS: 28 pacientes (16 mulheres; idade média 56 +- 11 anos; CVF 57 +- 17% predito) foram avaliados, e todos apresentavam padrão ventilatório restritivo sem resposta broncodilatadora. Na FOT, 4 pacientes apresentaram resistência aumentada a 5 Hz (R5), enquanto todos apresentaram baixa reactância (X5), sendo que nenhum apresentou resposta broncodilatadora significativa. Pacientes com PH crônica tiveram menor capacidade de exercício com menor O2 de pico, diminuição da reserva ventilatória, hiperventilação, dessaturação de oxigênio e escores de dispneia (Borg) aumentados quando comparado aos controles. A prevalência de HD foi encontrada em apenas 18% da coorte. Ao comparar pacientes com PH crônica com O2 normal e baixo ( 20 pack-years, supplemental oxygen use; previous diagnosis of asthma or COPD; pulmonary arterial hypertension, or medical conditions that could interfere with CPET. Data were compared with healthy controls. RESULTS: All patients (16 women; mean age 56 +- 11 years; FVC 57 +- 17% predicted) had restrictive ventilatory pattern without bronchodilator response. In FOT, 4 patients had increased resistance at 5 Hz (R5), all patients presented low reactance (X5) values, and none presented a significant bronchodilator response. Chronic HP patients had reduced exercise performance with lower peak V?O2, diminished breathing reserve, hyperventilation, oxygen desaturation and augmented Borg dyspnea scores when compared with controls. The prevalence of DH was only found in 18% of patients. When comparing chronic HP patients with normal and low peak VO2 (< 84%predicted, LLN), the later exhibited higher hyperventilation (VE/VCO2 slope), lower tidal volumes, and poorer physical functioning scores on Short-form-36 health survey. ROC curve analysis showed that reduced lung volumes (FVC%, TLC% and DLCO%) were high predictors of poor exercise capacity. On CT, chronic HP is characterized by increased pulmonary densities (Hounsfield Units) inferring the extension of ground glass opacities and fibrosis when compared with healthy subjects. The extension of low attenuation areas (LAA) and AT in relation to the hole lung volume is low and does not correlate with PFT indexes of obstruction; however, patients with greater extension of these areas had less fibrosis and more preserved PFTs. CONCLUSIONS: Chronic HP was characterized by an imminently restrictive lung disorder, and not by airway obstruction, according to the different diagnostic methods applied in this study. Reduction of exercise capacity was prevalent due to ventilatory and gas exchange limitation, similarly to other fibrotic interstitial lung diseases, rather than due to DH. Reduced lung volumes were good predictors of ventilatory responses during exercis

Visão de fumantes sobre seu hábito e sobre as causas de sua doença após o diagnóstico de câncer de pulmão: um estudo clínico qualitativo

CONTEXT AND OBJECTIVE: Lung cancer is the commonest malignant tumor and is increasing in incidence by 2% a year. In 90% of diagnosed cases, it is associated with tobacco product consumption. It is the greatest cause of mortality among cancer types in Brazil. Knowledge of patients? psychological representations is needed for evaluating treatments and educating patients. The aim here was to interpret how smokers with lung cancer interpret the possible causes of their illness and to understand their perceptions regarding cigarette use. DESIGN AND SETTING: Clinical-qualitative study (exploratory, non-experimental) at the Pulmonary Disease Service, General Hospital, Universidade Estadual de Campinas. METHODS: An intentional small sample of cancer inpatients was recruited. The group was closed with 11 subjects, following attainment of data saturation from interviews. These interviews were semi-directed, with in-depth open-ended questions on interviewees? observations, applied in a confidential setting using a tape recorder. Interviewees? responses were categorized using qualitative content analysis and the results were assessed using interdisciplinary theoretical concepts, particularly from medical psychology. RESULTS: Six males and five females aged between 46 and 68 years who presented diverse clinical conditions were interviewed. CONCLUSIONS: A broader approach towards the psychological comprehension of such patients is needed, considering that cigarette consumption involves conscious and unconscious motivations, sociocultural and educational factors, the glamour of tobacco advertising, and problems with psychophysical dependence. Such an approach would avoid the perception among patients that the healthcare team are inquisitors. This would lead to better adherence to treatment and better quality of life.CONTEXTO E OBJETIVO: O câncer de pulmão é o mais comum dos tumores malignos, apresentando aumento de 2% ao ano em sua incidência mundial. Em 90% dos casos diagnosticados, está associado ao consumo de derivados de tabaco. No Brasil, é o câncer que mais faz vítimas fatais. É crucial aos médicos conhecer as representações psicológicas desses pacientes para preconizar tratamentos e educá-los. O objetivo deste trabalho é interpretar significados que fumantes com câncer de pulmão atribuem a possíveis causas da doença, bem como compreender percepções relacionadas ao uso do cigarro. TIPO DE ESTUDO E LOCAL: Desenho clínico-qualitativo (exploratório, não-experimental) realizado no Serviço de Pneumologia do Hospital das Clínicas da Universidade Estadual de Campinas, Campinas, São Paulo, Brasil. MÉTODOS: Amostra propositalmente pequena de pacientes internados com câncer; grupo fechado com 11 sujeitos quando ocorrida a saturação de informações das entrevistas. Entrevista semidirigida de questões abertas (entrevista em profundidade na observação acurada dos entrevistados) contendo poucos tópicos foi aplicada em ambiente confidencial, usando gravador de fita cassete. Após categorização do conjunto das falas, usando análise qualitativa de conteúdo, a discussão dos resultados empregou conceitos teóricos interdisciplinares, especialmente da psicologia médica. RESULTADOS: Entrevistamos seis homens e cinco mulheres, com idades variando entre 46 e 68 anos; sujeitos apresentando condições clínicas diversas. CONCLUSÃO: A compreensão psicológica desses pacientes exige uma abordagem mais ampla, considerando que o consumo de cigarros envolve motivações conscientes e inconscientes, fatores socioculturais e educacionais, glamourosa propaganda do tabaco e problemas de dependência físico-psíquica. Também evitaria o surgimento de figuras percebidas pelos pacientes como inquisidores dentre a equipe de saúde. Estas novas condições levariam à maior adesão ao tratamento e melhor qualidade de vida.12512