Pulmonary function and medication effect in mild-stage subjects with Parkinson's disease.

BACKGROUND: Parkinson's disease (PD) causes a series of movement disorders, many of them starting in the early stage. OBJECTIVE: To analyze the pulmonary function of mild-stage subjects with PD and to investigate the effects of levodopa on it. METHODS: We included 21 patients with idiopathic PD and 20 healthy control subjects. The participants were submitted to spirometry and impulse oscillometry assessments. The PD patients were evaluated during the "off" and "on" phases of their anti-PD medication, which was was converted to levodopa in an equivalent daily dose. A statistical analysis was performed with cross-sectional (PD patients "off" medication versus controls) and paired (PD patients "off" medication versus PD patients "on" medication) tests. The effect of levodopa was calculated with partial Eta-squared (η2 ρ). Significance was set at 5%. RESULTS: The PD patients presented normal values in the impulse oscillometry. Regarding spirometry, the results indicated an incipient obstructive ventilatory disorder in the PD group - confirmed by patients' flow-volume curves. The PD patients received a daily dose of 354.7 ± 148.2 mg of levodopa. The paired analyses showed a small effect of anti-PD medication on pulmonary parameters (η2 ρ = 0.197 for spirometry and η2 ρ= 0.043 for impulse oscillometry). CONCLUSION: Patients with PD in the mild stage of the disease present pulmonary compliance and resistance compatible with normal parameters. The differences regarding the spirometric results indicate an incipient obstructive ventilatory disorder in patients with PD. Levodopa had small effect on pulmonary function in the mild stage of the disease.

ANTECEDENTES: A doença de Parkinson (DP) causa uma série de distúrbios do movimento, muitos deles se desenvolvendo na fase inicial. OBJETIVO: Analisar função pulmonar de pessoas com DP em estágio leve e investigar o efeito da levodopa nesse processo. MéTODOS: Vinte e um participantes com DP idiopática e vinte controles saudáveis foram incluídos na pesquisa. Todos os sujeitos foram submetidos a avaliações de espirometria e oscilometria de impulso. Participantes com DP foram avaliados nas fases 'on' e 'off' de medicação anti-parkinsoniana. A medicação dos pacientes foi convertida em dose diária de levodopa. A análise estatística foi realizada com testes transversais (Parkinson na fase 'off' da medicação vs controles) e pareados (Parkinson nas fases 'off' vs 'on' da medicação). O efeito da levodopa foi calculado pelo eta ao quadrado parcial (η2 ρ). Significância foi estipulada em 5%. RESULTADOS: Pacientes com DP apresentaram valores normais na oscilometria de impulso. Na espirometria, os resultados indicaram uma desordem ventilatória obstrutiva incipiente no grupo DP ­ confirmada pelas curvas fluxo-volume dos pacientes. Pacientes com DP receberam uma dose diária de 354,7 ± 148,2 miligramas de levodopa. Análises pareadas mostraram baixo impacto da medicação anti-parkinsoniana nos parâmetros pulmonares (η2 ρ = 0,197 na espirometria e η2 ρ = 0,043 na oscilometria de impulso). CONCLUSãO: Pacientes com DP na fase leve apresentam complacência e resistência pulmonares compatíveis com parâmetros normais. Diferenças espirométricas indicam distúrbio ventilatório obstrutivo incipiente em pacientes com DP. A administração de levodopa apresentou baixo efeito na função pulmonar na fase leve da doença.

Pulmonary function and medication effect in mild-stage subjects with Parkinson's disease / Função pulmonar e efeitos da medicação em pessoas com doença de Parkinson em estágio leve

Abstract Background Parkinson's disease (PD) causes a series of movement disorders, many of them starting in the early stage. Objective To analyze the pulmonary function of mild-stage subjects with PD and to investigate the effects of levodopa on it. Methods We included 21 patients with idiopathic PD and 20 healthy control subjects. The participants were submitted to spirometry and impulse oscillometry assessments. The PD patients were evaluated during the "off" and "on" phases of their anti-PD medication, which was was converted to levodopa in an equivalent daily dose. A statistical analysis was performed with cross-sectional (PD patients "off" medication versus controls) and paired (PD patients "off" medication versus PD patients "on" medication) tests. The effect of levodopa was calculated with partial Eta-squared (η2ρ). Significance was set at 5%. Results The PD patients presented normal values in the impulse oscillometry. Regarding spirometry, the results indicated an incipient obstructive ventilatory disorder in the PD group - confirmed by patients' flow-volume curves. The PD patients received a daily dose of 354.7 ± 148.2 mg of levodopa. The paired analyses showed a small effect of anti-PD medication on pulmonary parameters (η2ρ = 0.197 for spirometry and η2ρ = 0.043 for impulse oscillometry). Conclusion Patients with PD in the mild stage of the disease present pulmonary compliance and resistance compatible with normal parameters. The differences regarding the spirometric results indicate an incipient obstructive ventilatory disorder in patients with PD. Levodopa had small effect on pulmonary function in the mild stage of the disease.

Resumo Antecedentes A doença de Parkinson (DP) causa uma série de distúrbios do movimento, muitos deles se desenvolvendo na fase inicial. Objetivo Analisar função pulmonar de pessoas com DP em estágio leve e investigar o efeito da levodopa nesse processo. Métodos Vinte e um participantes com DP idiopática e vinte controles saudáveis foram incluídos na pesquisa. Todos os sujeitos foram submetidos a avaliações de espirometria e oscilometria de impulso. Participantes com DP foram avaliados nas fases 'on' e 'off' de medicação anti-parkinsoniana. A medicação dos pacientes foi convertida em dose diária de levodopa. A análise estatística foi realizada com testes transversais (Parkinson na fase 'off' da medicação vs controles) e pareados (Parkinson nas fases 'off' vs 'on' da medicação). O efeito da levodopa foi calculado pelo eta ao quadrado parcial (η2ρ). Significância foi estipulada em 5%. Resultados Pacientes com DP apresentaram valores normais na oscilometria de impulso. Na espirometria, os resultados indicaram uma desordem ventilatória obstrutiva incipiente no grupo DP - confirmada pelas curvas fluxo-volume dos pacientes. Pacientes com DP receberam uma dose diária de 354,7 ± 148,2 miligramas de levodopa. Análises pareadas mostraram baixo impacto da medicação anti-parkinsoniana nos parâmetros pulmonares (η2ρ = 0,197 na espirometria e η2ρ = 0,043 na oscilometria de impulso). Conclusão Pacientes com DP na fase leve apresentam complacência e resistência pulmonares compatíveis com parâmetros normais. Diferenças espirométricas indicam distúrbio ventilatório obstrutivo incipiente em pacientes com DP. A administração de levodopa apresentou baixo efeito na função pulmonar na fase leve da doença.

Inspiratory Muscle Training Potentiates the Beneficial Effects of Proportional Assisted Ventilation on Exertional Dyspnea and Exercise Tolerance in COPD: A Proof-of-Concept Randomized and Controlled Trial.

During pulmonary rehabilitation, a subset of subjects with COPD requires adjunct therapy to achieve high-intensity training. Both noninvasive ventilation (NIV) and inspiratory muscle training (IMT) are available to assist these subjects. We aimed to prime the respiratory muscles before NIV with IMT, anticipating additive effects for maximal exercise tolerance (Tlim) and dyspnea/leg fatigue relief throughout the exercise as primary outcomes. Changes in the respiratory pattern were secondary outcomes. COPD subjects performed a total of four identical constant work rate tests on a cycle ergometer at 75% of maximum work rate, under control ventilation (SHAM, 4 cm H2O) or proportional assisted ventilation (PAV, individually adjusted), before and after 10 sessions of high-intensity IMT (three times/week) during 30 days. Two-way RM ANOVA with appropriate corrections were performed. Final analysis in nine subjects showed improved Tlim (Δ = 111 s) and lower minute-ventilation (Δ = 4 L.min-1) at exhaustion, when comparing the IMT effects within the PAV modality (p = 0.001 and p = 0.036, respectively) and improved Tlim for PAV vs. SHAM (PAV main-effect, p = 0.001; IMT main-effect, p = 0.006; PAV vs. IMT interaction, p = 0.034). In addition, IMT + PAV association, compared to PAV alone, resulted in lower respiratory frequency (IMT main-effect, p = 0.009; time main-effect, p < 0.0001; IMT vs. time interaction, p = 0.242) and lower inspiratory time related to duty cycle (IMT main-effect, p = 0.018; time main-effect, p = 0.0001; IMT vs. time interaction, p = 0.004) throughout exercise. The addition of IMT prior to a PAV-supported aerobic bout potentiates exercise tolerance and dyspnea relief and induces favourable changes in ventilatory pattern in severe COPD during high-intensity training (Brazilian Registry of Clinical Trials, number RBR-6n3dzz).