COPD as a mind boggling issue requires a multifaceted methodology as to clinical appraisal and reaction to therapy. COPD prompts a decrease in exercise limit that influences the personal satisfaction and expands mortality of these patients. Various endeavors have been made to decide functional capacity in patients who have COPD. Gold global COPD guideline1-3 portrayed that spirometry is the gold standard for exact and repeatable measurement of lung function. Fev1 is utilized to characterize the seriousness of the sickness. Fev1 associates feebly with dyspnoea, representing just 12% of the fluctuation in dyspnoea as estimated by the baseline dyspnoea index (BDI). A few patients are not constrained in their exercises notwithstanding when fev1 is diminished to 35% of anticipated worth, though others are kept to wheelchairs. This puzzle focuses to the requirement for other appraisal tools.4 Spirometry is anyway just a single method for deciphering COPD infection seriousness where spirometry isn't effectively accessible. Likewise, different estimates, for example, the MMRC dyspnoea scale. Quantitative evaluation of manifestations like dyspnoea, estimation of PEFR and exercise test like 6-minute walk test (6MWT), which are less expensive methods of diagnosis, can be considered to substitute the spirometry rather if spirometry isn't accessible then both organizing of the infection and follow up of patient should be possible based on seriousness of symptoms, PEFR and 6-MWT.5 Research center tests that evaluate functional capacity are tedious and exorbitant and are not very much acknowledged by patients. Exercise resistance evaluation of has picked up significance in understanding the effect of the sickness and following functional capacity changes coming about because of the infection movement or therapeutic intervention.6 The SIX MINUTE WALK TEST was created which was demonstrated to be dependable and legitimate as an appraisal for exercise resistance for COPD.7 To quantify the capacity to perform day by day living exercises. The 6-MWT is a goal strategy, to assess the functional status, screen therapy, or survey the prognosis in patients with pulmonary diseases., It is all the more regularly performed because of its straightforwardness, reasonableness, great unwavering quality, legitimacy and the negligible mechanical necessities are the principle points of interest of the 6-MWT, just as the way that vital signs and symptoms can be estimated during the test. Pretty much every patient is equipped for understanding the impacts of the treatment, with the exception of those that are most influenced by sickness.8 To assess the improvement in COPD patients following the standard treatment, an unassuming exertion was taken. In this examination, the level of progress was recorded in the follow up visits of standardized treatment and it was contrasted and spirometric parameters.

Main Objective The study aim to evaluate 6 minute walk test in patients of chronic obstructive pulmonary disease. Specific objectives • To identify the severity of the COPD patient, • To analyze the outcome standard treatment, and • To measure the outcomes with 6-MWT. MATERIALS AND METHODS This prospective observational and comparative study was done in order to gauze the improvements of functional status with progressive time in COPD patients in Rama Medical College, Hospital & Research Centre, Hapur, as a quick and inexpensive standard tool. On the basis of the inclusion criteria and exclusion criteria, initially, 150 cases were enrolled in the study. Of them 100 patients completed two follow-ups and were included in the final analysis of the study. Inclusion Criteria The inclusion criteria of this study are: ▪ Clinical diagnosis of COPD, as defined by GOLD. ▪ Respiratory symptoms (Cough, shortness of breath and sputum production) ▪ Clinically stable airway obstruction. ▪ Participants, who gave consent and were willing to comply with the study procedures Exclusion Criteria Extremely severe patients of the Pulmonary Disease were directly excluded as the study requires the patients to have a comparatively higher functional status as well as sound mind.

On the basis of the inclusion and exclusion criteria initially 150 patients were enrolled in the study. Of them 100 cases completed two follow-ups and were included in the final analysis for the study. The findings derived from the data analysis are presented in table 1. Figure-2 depicts the smoking status/situation of the 100 samples. Majority of the patients were smokers (64%) and about one-third (30%) of the patients were in the process of quitting smoking or ex-smoker. Only 6 patients (6%) were complete non-smokers. Table 2 depicts the COPD staging of the patients in the start of the observation process of the study. Majority of the patients belonged in Stage 3 of the disease followed by the stage 4 patients. Table 3, figure-3, and figure 4 detail the 1st and 2nd follow up after the baseline measure and comparison of desaturation after 6MWT between Baseline and During Follow-up. Figure-5 shows the relationship between 6-MWT and The FEV1 and figure 6 shows the comparison at 1st follow-up. On the other hand, table 4 details the comparative analysis of FEV1 during the 1st and 2nd follow up data with the baseline dataset. Figure 7 shows the correlation of the 1st follow up CAT score with the 6-MWT analysis of the same visitation of the patients. Then, the change in the FEV1 and FVC at the 1st follows up and the 2nd follow up is respectively shown in the table 5 and table 6. Table 1: Distribution of the Patients as Per Body Mass Index (BMI). (n=100) BMI Frequency Percent (%) Underweight 40 40% Normal 51 51% Overweight 5 5% Obese 4 4% Total 100 100% Table 2: Distribution of the patients according to stages of COPD at baseline COPD Stage at baseline No. of Patients Percent (%) Stage 1 1 1 Stage 2 24 24 Stage 3 48 48 Stage 4 27 27 Total 100 100 Table 3: Comparison of 6-Minute Walk Distance (6MWD) between baseline and follow-up visits in different stages of COPD. Stage of COPD Baseline (mean ± SD) At 1st follow up (mean ± SD) At 2nd follow up (mean ± SD) Stage 1 1040 1090 1270 Stage 2 1122.31 (±170.442) 1285.04 (±214.263) 1378.68 (±203.928) Stage 3 950.95 (±319.384) 1096.39 (±281.423) 1212.36 (±290.717) Stage 4 774.77 (±302.765) 900.00 (±312.050) 1067.63 (±276.308) Table 4: Comparison between baseline and follow-up FEV1. Parameter Baseline (mean ± SD) At 1st follow-up (mean ± SD) At 2nd follow-up (mean ± SD) FEV1 (% of predicted) 40.11 (±14.41) 42.60 (±15.82) 44.04 (±15.90) Table 5: Change in FEV1 & FVC at 1st follow-up Baseline values of the parameter (mean ± SD) Change in parameters (mean ± SD) % of increase in the parameter p-value FEV1 *40.11 (±14.48) 2.49 (±6.45) 6.21 <0.001 FVC* 66.35 (±19.16) 3.93 (±6.027) 5.92 <0.001 Table 6: Change in FEV1 & FVC at 2nd follow-up Baseline values of the parameter (mean ± SD) Change in parameters (mean ± SD) % of increase in the parameter p-value FEV1 *40.12 (±14.48) 3.93 (±6.03) 9.8 <0.001 FVC* 66.34 (±19.16) 3.42 (±9.731) 5.14 <0.001

Initially 150 patients were enrolled in the study. Out of them 100 patients completed the required two follow ups; first follow up was after 2 weeks of standard optimum treatment, and the second and last one was after 12 weeks of standard optimum treatment. The causes of drop outs were death in 4 patients, then the later diagnosis associated Bronchial Carcinoma in 5 patients while the rest of the patients refuse to come due to economic or behavioral constrain. Majorities the patients were smokers (64.6 %) and had normal BMI at 51%. Regarding the stage or severity of the disease, about 48% of the patients had stage 3 COPD; almost 27% of the patients had stage 4 and stage 2 COPD (24%). Additionally, Gautam et al. (2014) in their study found almost the number of stage 2 (40.2%) and stage 3 (42.7%) patients. At baseline, 42 patients had desaturation after 6MWT evidenced by ≥ 3% fall of O2 saturation. But level of desaturation after 6MWT lessened considerably during follow up visits, which was statistically significant (p<0.001). In this study, 100 patients were examined at baseline and during the two follow ups for 6-Minute Walk Distance (6MWD). After getting standard optimum treatment changes in 6MWD in different stages of COPD were appraised. A significant increase was observed in the stage 2, 3, and 4. When the patients of all stages added up together the increase in 6MWD at 1st follow-up was at almost 144.2 (±170.4) feet and that of the 2nd follow up was 262.6 (±197.00) feet. COPD Assessment Test (CAT) scores were measured and compared between baseline and follow up visits. It was observed that the scores decreased significantly during follow up visits (p<0.001). Two previous prospective studies have demonstrated that the 6MWT is a better predictor of mortality than FEV1 in patients with very severe COPD.9 6MWT result in patients suffering from COPD has been found to be more reproducible than the measurement of FEV1.10 Moreover and it was more sensitive in differentiating patients with low or high work capacity.11

In conclusion, 6MWD has positive correlation with FEV1 and strong negative correlation with CAT score in the two follow up visits of COPD patients. After many different analysis, it is clearly visible that 6MWT can be used as an alternative tool in monitoring of treatment outcome of COPD patients in areas where spirometry is not available and because of its safety, simplicity, inexpensiveness, better reflectivity of changes in quality of life and it signify visible improvement by patient as patient can’t understand improvement in FEV1.

1. Davidson,s, 2018, Principle & practice of medicine, Elsevier, 23rd Edition. 2. GOLD: pocket guide to COPD diagnosis, Management and prevention-2018 report. 3. GOLD international COPD guideline- 2014. 4. Somanath Dash, Anil Kumar Kodavala, Samir Ranjan Nayak, K. V. Ramana Rao, N. Durga Prasad, Saladi Sridurga. Pyopneumothorax with An Unusual Etiology, IJCRR 2013; 5(10):76-83. 5. Pankaj N Maheshwari, Nitin Joshi, Reeta P Maheshwari. Best laser for prostatectomy in the year 2013, Indian Journal of Urology 2013; 29(3): 236-43. 6. Butland et al. Two-, six-, and 12-minute walking tests in respiratory disease. PMC 1982; May 29;284(6329):1607-8. 7. Casanova M, et al. Inhibition of active nuclear transport is an intrinsic trigger of programmed cell death in trypanosomatids. Cell Death Differ 2008; 15(12):1910-20. 8. Am J Respir Crit Care Med. 2003, Erratum: ATS Statement: Guidelines for the Six-Minute Walk Test. 9. Pinto- Plata, VM et al. 2004. The 6-min walk distance: change over time and value as a predictor of survival in severe COPD, Eur Respir J. 2004 Jan;23(1):28-33. 10. Knox, P. Planning and applied geography. Progress in Human Geography 1988; 12(4), 567–574. https://doi.org/10.1177/030913258801200408 11. Six-Minute Walk Test to Assess COPD Patients. Am Fam Physician. 2004 Jan 1;69(1):172-174.