‘’COMPARATIVE STUDY OF SIX MINUTE WALK TEST AND SIT-TO-STAND TEST IN COPD PATIENTS IN RESOURCE LIMITING SETTING’’

Abstract

Introduction- COPD is a heterogeneous lung condition characterized by chronic respiratory symptoms (dyspnea, cough, sputum production) due to abnormalities of the airways (bronchitis, bronchiolitis) and/or alveoli (emphysema) that cause persistent, often progressive, airflow obstruction. Among the various clinical tools available, two prominent tests have gained recognition for evaluating functional capacity in this population: the Six Minute Walk Test (6MWT) and the Sit-to-Stand Test (STST).

Aims and objective- this is a cross sectional study done in department of pulmonary medicine, birsa minda government medical college Shahdol from Feb 2022 to April 2023.  This study aimed at systematically analysis the diagnostic and clinical utility of the 6MWT and the STST in the context of COPD, with the goal of elucidating which test may be more advantageous for evaluating functional capacity and exercise tolerance. This study done in comprehensively examining the strengths, weaknesses, and clinical implications of each test, we seek to provide empirical evidence to guide healthcare practitioners in selecting the most appropriate assessment tool for COPD patients in resource limiting clinical setting.

Materials and methods. There were total of 97 participants diagnosed with COPD and remaining 194 were controls who did not had COPD. The adult patients of both genders diagnosed with COPD and belonging to either category I and II of the GOLD’s criteria and stable disease status at the time of assessment were included in the present study as ‘cases’. A comparative diagnostic accuracy study was conducted to assess the performance of the Six Minute Walk Test (6MWT) and the Sit-to-Stand Test (STST) in measuring functional capacity in patients diagnosed with Chronic Obstructive Pulmonary Disease (COPD). This study adhered to the STARD (Standards for Reporting of Diagnostic Accuracy) guidelines for the evaluation of diagnostic tests.  A total 291 participants completed both the 6-Minute Walk Test (6MWT) and the Sit-to-Stand Test (STST). Diagnostic accuracy measures, including sensitivity, specificity, and area under the receiver operating characteristic curve (AUCROC), were calculated to evaluate the performance of the 6MWT and STST.

Results- There was a total of 238 men and 53 women participants. The mean age was 48.6 years (SD = 4.1), with a range of 37 to 56 years. The mean body mass index (BMI) was 24.3 kg/m² (SD = 2.1), and the mean smoking history was 16.8 pack-years (SD = 3.6). Based on the GOLD’s criteria- 56 (57.7%) participants had grade I COPD and 41 participants had grade II COPD (42.2%). Overall, the average distances covered in the 6MWT were 451.1 meters (SD ±84.3) and the mean number of repetitions performed in the STST 19.8 repetitions (SD ±6.5), respectively. No significant connections were observed between the number of repetitions and factors such as height, weight, or BMI. The reliability of both the STST and the 6MWT was determined to be excellent, with Intraclass Correlation Coefficients (ICC) surpassing 0.9. Both 6 MWT and STST, the sensitivity was lower for patients having grade I COPD (sensitivity 76%) and higher for patients with grade II COPD (91.3%).  The 6MWT provides a broader assessment of overall functional capacity and cardiovascular fitness compared to the more specific focus of the STST on lower limb strength.

Conclusion- Both 6 MWT and STST, the sensitivity was lower for patients having grade I COPD (sensitivity 76%) and higher for patients with grade II COPD (91.3%).  The 6MWT provides a broader assessment of overall functional capacity and cardiovascular fitness compared to the more specific focus of the STST on lower limb strength.