ABSTRACT

PURPOSE: Characteristic reduced endurance and excessive fatigue in Stroke Survivors (SS) during exercise may be linked to impairment of lung function and breathing mechanics, but little is known about the lung function of SS. The purpose of this study was to determine forced expiratory volume in one second (FEV₁), forced vital capacity (FVC), peak expiratory flow (PEF) and the influence of anthropometrics, duration of stroke and affected side on FEV₁, FVC and PEF of Stroke Survivors compared with age- and sex-matched healthy controls.  

RELEVANCE: Stroke is a global health problem and the percentage of stroke recurrence seems to be particularly high; within 5 years, between 20% and 37% will have had a further stroke event. Hemiparetic stroke survivors often show fatigue and dyspnea in conditions of higher effort demands, which in turn may interfere with the performance of activities of daily living. The findings of this study suggests that stroke reduce lung function of SS which calls for routine assessment of pulmonary system and inclusion of respiratory muscles training to improve pulmonary function of SS.

PARTICIPANTS: Seventy participants (42 males, 28 females), comprising 35 SS and 35 age- and sex- matched control group (CG) whose ages ranged from 34 to 73 years were recruited for this study. The SS were patients attending 3 purposively selected physiotherapy outpatient departments. The CG were recruited among patients’ relatives, healthcare workers and retirees group.

METHODS: This study was a cross-sectional, case-control study. Ethical approval was obtained from Ethics and Research committee of Obafemi Awolowo University Teaching Hospital, Ile-Ife, Nigeria (ERC/2011/05/05). Questionnaire were administered to the participants to obtain information on socio-demographic factors, affected side, duration of stroke, smoking and cough history. Height, weight and vital signs were measured using standard instruments and procedure. Chest excursion was measured at the axilla, xiphoid and lower costal levels.  Lung function indices (FEV₁, FVC and PEF) were measured using a micro-computerised spirometer.

ANALYSIS: Means, standard deviation, range and percentages were used to summarize data, Student’s t-test, Pearson’s correlation and multiple regression analysis were used for analysis.

RESULTS: There were no significant differences between the SS and CG in age (55.8 ± 8.99 vs. 55.6 ± 9.03 years, p=0.701), height (1.65 ± 0.09 vs. 1.65 ± 0.08 meters, p=0.711), weight (69.5 ± 11.61 vs. 66.2 ± 11.35 kilograms, p=0.215) and BMI (25.6 ± 3.63 vs. 24.2 ± 3.53 kg/m², p=0.095). The results indicate the homogeneity of the participants. Compared to the SS, the CG had significantly higher values for FEV₁ (1.99 ± 0.66 vs. 2.36 ± 0.45 litres, p= 0.004), FVC (2.55 ± 0.70 vs. 2.90 ± 0.54 litres, p=0.014) and PEF (3.88 ± 1.38 vs. 5.24 ± 1.30 litres/second, p=0.001). In addition, the chest excursion was significantly higher for CG when compared with SS (3.5 ± 0.91 vs. 3.0 ± 0.71cm, p=0.018). Significant relationships were found for SS, between age and FEV₁ and FVC (r= -0.549 and -0.514, p<0.01) and between height and FEV₁, FVC and PEF (r= 0.500, 0.566 and 0.457 respectively, p<0.01). Weak positive relationships were found between duration of stroke and FEV₁, FVC and PEF (r = 0.192, 0.190 and 0.213 respectively, p>0.05). Regression analysis showed that height and age were the viable predictors for FEV₁, FVC and PEF of SS for male and female participants.

CONCLUSION: This study found significantly lower FEV₁, FVC and PEF of SS when compared with CG, this has implications for clinicians in stroke rehabilitation, underscoring the importance for assessment of pulmonary system and inclusion of interventions to improve lung function in SS.

Keywords: Lung Function, Stroke Survivors, Spirometry.