The effect of on respiratory functions, lung diffusion capacity, functional capacity and asthma control in adult asthmatic i̇ndividuals

Asthma is a chronic inflammatory disease of the airways characterized by persistent cough, wheezing, shortness of breath or shortness of breath that increases during exercise. Obesity is a chronic disease characterized by an increase in body fat mass caused by the excess of the power generated by the nutrients taken into the body with food over the power expended. It is claimed that respiratory movement is restricted as a result of mechanical compression of the thorax and abdominal system by the adipose tissue formed by weight gain in the body. The reduced airway with restriction reduces respiratory volume and lung capacity. In addition, although the relationship between obesity and asthma has not been fully explained, the inflammatory and mechanical effects of obesity on the lungs are considered as possible effects. In the literature; in studies conducted with obesity groups in asthma patients, it has been reported that overweight patients have difficulty in breathing and asthma attacks increase. Therefore, we aimed to determine the effect of obesity on pulmonary function, lung diffusion capacity, functional capacity and asthma control in adult asthmatic subjects. In our study, 50 patients who were followed up in the Department of Chest Diseases, Sisli Kolan International Hospital, with a diagnosis of asthma, met the inclusion criteria and voluntarily agreed to participate in the study were included. Patients were divided into two groups as obese and non-obese asthma patients. Body Mass Index (BMI), Asthma Control Test (ACT), Pulmonary Function Test, Lung Diffusion Capacity (DLcO) and Six Minute Walking Test (6MWTM) were measured in all patients. SPSS v.26 program was used for data analysis. Shapiro-Wilk test was used to analyze whether the data were normally distributed. The analysis of qualitative variables was interpreted with X2-test. Indepedent Sample T-test was used for comparison between groups in numerical data showing normal distribution. Mann Whitney U test was used for comparisons between groups that did not show normal distribution. One Sample T test was used to compare with healthy population data. The relationship between the data was evaluated by Pearson or Spearman correlation test. Statistical significance level was accepted as p<0.05 for all analyzes. No significant difference was found between the groups in the study except for weight and body mass index. There was no significant difference between the severity of asthma disease, ACT and medication use of the patients in the obese and non-obese groups. No significant difference was found in SFT and DLCO results between adult obese asthmatic subjects and non-obese asthmatic subjects (p>0.05). When the 6DYT test values of the groups in the study were compared, no significant difference was found between obese and non-obese asthma patients in SpO2 end values (p=0.045), SDB initial (p=0.017) and end (p=0.002) values, respiratory frequency end values (P=0. 002), dyspnea and fatigue perception at baseline (p=0.004, p= 0.0.18) and end (p=0.010, p=0.026), leg pain at end (p= 0.045) and walking distance (p=0.038). When we examined the relationship between BMI and SFT, DLCO and functional capacity, a moderate significant correlation was found between BMI and 6DYT distance (r=-0.592, p=0.028). In conclusion, our study showed that functional capacity is affected in asthma patients even if the severity of the disease is mild when compared with healthy population data. Although there was no difference in respiratory functional capacity parameters and asthma control in asthmatic patients with and without obesity, significant differences were found in one of the life determinants such as functional capacity. This shows the importance of obesity in terms of life expectancy in asthma patients. Keywords: Asthma, Lung Diffusion Capacity, Pulmonary Function, Obesity, Functional Capacity