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The Third PLeural Effusion And Symptom Evaluation (PLEASE-3) study: bendopnoea in patients with pleural effusion
Bianca M Iacopetta1,2,3, Bapti Roy2,4, Charley A Budgeon5,6
1Institute for Respiratory Health, Pleural Medicine Unit, Perth, Australia.
Background:
Bendopnoea (breathlessness on bending forward) is reported often by patients with pleural effusion, but its prevalence and clinical relevance are unexplored.
Methods:
This study prospectively enrolled unselected patients with pleural effusion. Bendopnoea was assessed by time to breathlessness when bending patients forward for up to 60 s (60-s bend test (60s-BT)). Post-hoc analyses using a 30-s cut-off were also conducted.
Results:
200 patients (median age 72 years; 61% male) were included; n=88 underwent therapeutic drainage (median (interquartile range (IQR)) 1.50 (1.11-2.47) L). Effusions were commonly malignant (42%) and occupied >25% of the hemithorax (74%). Most patients had bendopnoea on the 60s-BT (56%) and reported it "impacted daily activities" (74%). The estimated median time to bendopnoea was 43 (95% CI 30-59) s. Bendopnoea was more common with larger pleural effusions on chest radiographs (p=0.0332 using 60-s cut-off and p=0.0217 using 30-s cut-off). Patients with bendopnoea on the 60s-BT were more breathless (median (IQR) 48 (22-67) versus 30 (5-54) mm on a 100-mm Visual Analogue Scale; p=0.0002) and had shorter 6-min walk distance (6MWD) (median (IQR) 200 (128-333) versus 310 (223-371) m; p=0.0013). Similar relevance was found using a 30-s cut-off. The proportion of patients with bendopnoea on the 60s-BT significantly decreased from 62% to 32% post-drainage (p<0.001). Those with bendopnoea (versus those without) had significantly greater improvement in 6MWD post-drainage (median (IQR) 66 (2-101) versus 16 (-40-65) m; p=0.0165). Larger effusion (OR 5.08, 95% CI 1.25-20.66), inverted/flattened hemidiaphragm on ultrasonography (OR 3.93, 95% CI 1.32-11.68) and higher body mass index (OR 1.18, 95% CI 1.08-1.28) were associated with bendopnoea (60s-BT) in multivariable analysis.
Conclusion:
Bendopnoea is a simple and worthwhile symptom to recognise in patients with pleural effusion.
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