Beekman E, Mesters I, de Rooij M, de Vries N, Werkman M, et al. Therapeutic Consequences for Physical Therapy of Comorbidity Highly Prevalent in COPD: A Multi –case Study. Journal of Allergy and Therapy 2013: S2: 004.
Introduction: Comorbidities are prevalent in patients with chronic obstructive pulmonary disease (COPD), but current physical therapy guidelines do not incorporate clear actions related to multimorbidity. Comorbidity (e.g. diabetes mellitus) may require adaptations in intervention strategies, as comorbidity negatively affect treatment results of the index disease (e.g. COPD) or treatment for one disease (e.g. cardiopulmonary endurance training for COPD) may negatively interact with the treatment or natural course of a coexisting disease (e.g. severe osteoarthritis of the knee). Therefore, insight of considerations required when applying physical therapy in comorbid-COPD patients and suggestions to enhance and accelerate clinical reasoning may be helpful for health care providers to obtain optimal treatment and results. Case description: Two case studies illustrated possible consequences of COPD (index disease) and comorbidity for physical therapy in a primary care setting. Avoidable and inescapable problems were both unfolded in different steps in the clinical decision-making process. One very severe COPD patient (FEV1 = 46% predicted, with chronic respiratory failure) with decompensated heart failure, using a beta-adrenergic blocker, demonstrated the danger of missing relevant information about a comorbid condition and related medication during the intake and its consequences for physical therapy. Another mild COPD patient (FEV1 = 86% predicted) with multiple inter-related comorbidities showed the importance of monitoring outcomes of multiple diseases and adjustments to the plan-of care and interventions. Discussion: Dealing with comorbidity in COPD management needs a patient-centred rather than a diseaseoriented approach in order to obtain optimal treatment and results. Physical therapists should improve their skills and knowledge of high prevalent comorbidities, be fully informed, monitor more than COPD-outcomes alone and adequately adjust interventions. General practitioners and physicians can improve the level of information given in their referral of a patient to a physical therapist, by providing information on all coexisting diseases and related medication.
Beekman E, Mesters I, Hendriks EJM, Klaasen MPM, Gosselink R, van Schayck CP, de Bie RA. Course length of 30 metre versus 10 metre has a significant influence on six-minute walk distance in patients with COPD: an experimental crossover study. Journal of Physiotherapy 2013; 59: 169-176.
Questions: Do patients with chronic obstructive pulmonary disease (COPD) achieve a different distance on the six-minute walk test (6MWT) conducted on a 10 m course versus on a 30 m course? What is the effect of the 10 m course length on predicted values for the 6MWT distance calculated with existing reference equations? Design: A randomised double-crossover experimental study. Participants: Forty-five patients with COPD in primary physiotherapy care. Intervention: All patients performed a 6MWT twice over a 10 m course and twice over a 30 m course. The 6MWTs were performed in accordance with the American Thoracic Society guidelines. Outcome measures: 6MWT distance was assessed and predicted distance was calculated based on a range of reference equations. Results: The 6MWT distance on the 10 m course was 49.5 m shorter than on the 30 m course, which was statistically significant (95% CI 39.4 to 59.6). By using existing reference equations for a 6MWT conducted on the 10 m course, the predicted distance is highly overestimated (with a range of 30% to 33%) and the average distance as a percentage of the predicted value is 8%pred lower compared to a 6MWT conducted on the 30 m course, resulting in a worse representation of a COPD patient’s functional exercise capacity. Conclusion: This study shows that the impact of course length on the 6MWT distance and on the use of reference equations in patients with COPD is substantial and clinically relevant (based on the most conservative published minimal clinical important difference). Therefore, existing reference equations established for a 6MWT conducted on a 30 m (or longer) course cannot be applied to predict the distance achieved on the 6MWT on a 10 m course, which is frequently used in primary care physiotherapy practices for patients with COPD.
Keywords: Chronic obstructive pulmonary disease, Course length, Exercise test, Reference values, 6-minute walk test