Abstract Background: Lung diseases and different forms of breathing may interfere with cardiac autonomic modulation (CAM). Objective: To compare CAM in individuals with chronic obstructive pulmonary disease (COPD) with healthy individuals during spontaneous breathing (SB) and controlled breathing (CB). Methods: Cross-sectional study involving 30 individuals selected by convenience, divided into COPD group (n = 19) and control group (CG; n = 12). All participants were submitted to heart beat recordings during five minutes at rest (SB) and another five minutes during CB performed at six cycles/min. CAM was made by assessment of the heart rate variability (HRV) through time domain (TD) and frequency domain (FD). Comparisons between groups were performed by Mann Whitney test, and significance level was set at p < 0.05. Results: During SB, HRV TD and FD indices were higher in the controls than in the COPD group, respectively - RR intervals (53.2 ms versus 36.6 ms), RMSSD (42.1 ms versus 26.6 ms) (p < 0.05), total power (28322.8 ms2/Hz versus 2011.6 ms2/Hz), and high-frequency band (800.5 ms(2) versus 330.7 ms2). During CB, the CG also showed higher values for the TD parameters pNN50 (11.7% versus 5.1%), RMSSD (48.3 ms versus 26.7 ms), and SD of RRi (64.9 ms versus 44.7 ms), as well as for the low-frequency component of FD analysis (2848.6 ms2 versus 1197.9 ms2). Conclusion: COPD patients have different CAM when compared with healthy individuals during spontaneous (SB) and controlled breathing (CB).

RESUMO Objetivo Avaliar a concordância entre as medidas de controle da asma e a capacidade de exercício funcional em crianças e adolescentes com asma não controlada e controlada. Métodos Selecionamos crianças e adolescentes com asma de 7 a 17 anos, que foram atendidos no Ambulatório de Pneumologia Pediátrica da Universidade Estadual de Campinas. Todos os pacientes tiveram nível de controle da asma avaliado pelo questionário da Global Initiative for Asthma (GINAq), Teste de Controle da Asma (TCA), espirometria e teste de caminhada de seis minutos (TC6M). Os pacientes foram classificados como asma não controlada ou controlada em cada teste e a concordância entre as medidas foi avaliada pelas estatísticas do Kappa. A curva ROC foi calculada para o TC6M. O índice espirométrico da espirometria foi composto por FEV1, FEV1/FVC e FEF25-75%. Os resultados da espirometria e do TC6M foram comparados entre o grupo de asma não controlada e controlada pela GINAq. Resultados Dos 138 sujeitos incluídos, 78 (56,5%) eram do sexo masculino com idade média de 11,00 (7-17) anos. O GINAq detectou 68,8% dos pacientes com asma não controlada. Foi observada concordância moderada (p<0,001; k=0,56) e alta especificidade (100%) entre o GINAq e o TCA. No TC6M, o ponto de corte de 82,03% da distância prevista possibilitou a distinção de pacientes com asma controlada e não controlada. O índice espirométrico apresentou 73,4% de sensibilidade com o GINAq. Foram observados resultados piores no TC6M em pacientes com asma não controlada. Conclusões Este estudo destaca a importância de avaliar mais de uma medida para diferenciar o nível de controle da asma. O GINAq identificou mais pacientes com asma não controlada e apresentou concordância moderada com o TCA. O índice espirométrico foi associado à asma não controlada de acordo com o GINAq. O TC6M foi uma boa medida para distinguir pacientes com asma controlada e não controlada.

ABSTRACT Objective To assess the agreement among asthma control measures and functional exercise capacity in children and adolescents with uncontrolled and controlled asthma. Methods Children and adolescents with asthma from 7-17 years old were selected, and they were attended in the “Pediatric Pulmonology Outpatient Clinic of State University of Campinas”, in Brazil. All patients had asthma control level assessed by Global Initiative for Asthma questionnaire (GINAq), Asthma Control Test (ACT), spirometry and six-minute-walk-test (6MWT). Patients were classified as uncontrolled or controlled asthma in each test and agreement among measures was assessed by kappa statistics. The ROC curve was calculated for the 6MWT. The spirometric index obtained from spirometry was composed by FEV1, FEV1/FVC and FEF25-75%. Spirometry and 6MWT results were compared between uncontrolled and controlled asthma group by GINAq. Results Of the 138 subjects included, 78 (56.5%) were male with median age of 11 (7-17) years old. GINAq detected 68.8% of patients with uncontrolled asthma. Moderate agreement (p < 0.001; k = 0.56) and high specificity (100%) was observed between GINAq and ACT. In 6MWT, the cut-off point of 82.03% of predicted distance was able to distinguish patients with controlled and uncontrolled asthma. Spirometric index presented 73.4% of sensitivity according to GINAq. The results for 6MWT in patients with uncontrolled asthma were the worst of all. Conclusion This study highlights the importance of assessing more than one measure to differentiate asthma control level. GINAq identified more patients with uncontrolled asthma and presented moderate agreement with ACT. Spirometric index was associated with uncontrolled asthma according to GINAq. 6MWT was a suitable measure to distinguish patients with controlled and uncontrolled asthma.