CORRELATION OF LUNG FUNCTION WITH PERCEIVED DYSPNEA, FUNCTIONAL INDEPENDENCE AND QUALITY OF LIFE IN STROKE SURVIVORS: A CROSS-SECTIONAL STUDY

Abstract

Background: Stroke is the leading cause of disability worldwide. Muscular weakness is one of the features of stroke in which respiratory muscles may be involved. Weakness of respiratory muscles associated with sedentary lifestyles and deconditioning, may increase dyspnea after stroke, increase the risk of respiratory complications leading to non-vascular death after stroke. Hemiparetic stroke survivors often show fatigue and dyspnea in conditions of higher effort demands which may interfere with activities of daily living and quality of life. Objective: The aim of this study was to assess lung function (forced vital capacity [FVC], forced expiratory volume in 1 second [FEV1], FEV1/FVC ratio and peak expiratory flow [PEF]) and its correlation with perceived dyspnea, functional activities of daily living and quality of life in stroke survivors. Methodology: This cross-sectional study included 72 stroke survivors (48 males, 24 females) between the age group of 18 to 50 years. They were selected on the basis of inclusion and exclusion criteria from New Civil Hospital, Surat. After taking consent from all the participants, outcome measures: Lung function by spirometer (CPFS/DTM USB spirometer), Perceived Dyspnea by Modified Borg Dyspnea Scale after 6-minute walk test (6MWT), Functional Independence by Barthel Index and Quality of Life by Stroke Impact Scale 3.0 were measured. Statistical analysis of the data was performed using MATLAB. All the data was analyzed by application of descriptive statistics, Wilcoxon signed-rank test, Mann-Whitney U test, Spearman’s rank correlation and Kruskal-Wallis one-way analysis of variance. Result: The data of outcome measures of stroke survivors was correlated and compared using Descriptive statistics, Non-parametric tests and Spearman’s rank correlation. The difference between absolute and predicted values for lung function indices (FVC [1.89±0.75 vs 3.62±0.724], FEV1 [1.64±0.57 vs 2.94±0.62], FEV1/FVC [88.04±10.86 vs 81.17±2.64] and PEF [3.38±1.67 vs 7.68±1.57]) were highly significant with p<0.01. Lung function parameters were statistically significant negatively correlated with post-test Modified Borg Dyspnea Scale (p-value<0.01) where as significant positively correlated with Barthel Index and Stroke Impact scale 3.0 (p-value<0.01) except FEV1. There was a strong association between activities of daily living and quality of life with p-value less than 0.01. Out of 8 domains of Stroke Impact Scale 3.0, Emotion and ADL/IADL domains were affected the most. Abnormal lung function represented by stroke survivor was restrictive lung defect (46 out of 72 participants). No statistically significant difference was observed between acute, sub-acute and chronic stroke survivors. Conclusion: Thus, we can conclude that stroke survivors had significant reduction in lung function and it was correlated with dyspnea, activities of daily living and quality of life. These findings will help to add valuable perspective to the prevention of respiratory complications following a stroke, inclusion of respiratory management in stroke rehabilitation programs and will provide inputs to current research on respiratory function.