Effects Of Smoking Cessation On Clinical Symptoms And Pulmonary Function In Patients With Chronic Obstructive Pulmonary Disease

Objective:Chronic Obstructive Pulmonary Disease (COPD),a common preventable and treatable disease,is characterized by persistent airflow limitation and is a common disease and frequently-occuring disease of respiratory system. In our country,the prevalence of COPD accounted for 8.2% of the population over the age of 40, which resulted in significant economic losses to society and the family. Many risk factors, smoking is the most important risk factor.Smoking cessation is an intervention that is the most efficient, cost-effective reduction in COPD risk and may slow down the progression of the disease. In our study, smoking cessation interventions were given to the smoking COPD patients and then observed the changes of the clinical symptoms, pulmonary function, quality of life and the exercise capacity after quitting which may provide reference for the clinical development of smoking cessation strategies.Methods:All the 315 subjects were recruited from the pulmonary department of Affiliated Hospital of Cheng De Medical College from December 2008 to October 2012, including 186 smokers,59 ex-smokers and 70 no-smokers.Give smoking cessation persuasion to all the smoking COPD patients and randomly divided them into two groups when they enrolling the test.One group was given common therapy, other group was given smoking cessation beside common therapy. After one year follow-up,COPD patients who successfully quitting were divided to smoking cessation group,otherwise were divided to smoking group.COPD patients in ex-smoking group and non-smoking group were all given common therapy. When enrolling the test, all the patients were consent to fill the questionnaire.When the patients were in stable stage, some tests were given to them, including clinical symptoms, pulmonary function(SVC, FVC, FEV1 and FEV1/FVC), peak expiratory flow (PEF), density of exhaled CO, six-minite walk test (6MWT) and BODE scores.In the first 3、6、9、12 month after the first test, all the COPD patients were recall or home follow-up to review the above-mentioned inicators and recorded the exacerbation frequencies.After 1 year follow-up, recorded the smoking cessation rates and analyzed the changes of the indicators.Results:1. Comparisons of smoking cessation rate(%) in two groups.1 year later,compared with therapy group,the smoking cessation rate of COPD patients in therapy and smoking cessation was significiantly higher, which is statistical significance in the difference(P<0.05). In all smoking cessation COPD patients, the male smoking cessation rate was higher than the female smoking cessation rate, there is statistical significance in the difference(P<0.05)2. Comparisons of clinical symptom scores among the four groups before and after 1 year follow-up time.1 year later, the clinical symptom scores in smoking cessation group was lower than the first test while the clinical symptom scores in smoking group is higher than the first test, there both were statistical significance in the difference(P<0.05). In the first test, the clinical symptom scores among the four groups were not significantly difference (P>0.05).1 year later, the clinical symptom scores in smoking cessation group was significantly lower than in the smoking group, there was statistical significance in the difference(P<0.05).The clinical symptom scores in smoking group was significantly higher than in both the ex-smoking group and the non-smoking group,there was statistical significance in the difference(P<0.05).3. Comparisons of exacerbation frequency among the four groups in 1 year.1 year later, the exacerbation frequency among the four group were significantly different (P<0.05) and the exacerbation frequency of smoking group was significantly higher than the other groups (P<0.05).4. Comparisons of pulmonary function and PEF among the four groups at different follow-up time.(1) Comparisons of pulmonary function among the four groups at different follow-up time. During the follow-up,the pulmonary function indicators were all increased. SVC was significantly higher than the first time in the 3 th,6th,9th and 12th month and there were all statistical significance in the difference(P<0.05). FVC, FEV1/FVC, and FEV1were also higher than the first test while there were not statistical significance in the difference(P>0.05).All the pulmonary function indicators in smoking group were decreased during the follow-up. SVC, FEV1/FVC and FEV1 in the 9th and 12th month were lower than the first test and FVC was lower than the first test in the 12th month only. There both were statistical significance in the difference(P<0.05).During the follow-up, the pulmonary function indicators in both ex-smoking cessation group and non-smoking cessation group were decreased than the first test while there were not statistical significance in the difference(P>0.05).In the first test, there were not statistical significance in the difference among the four groups (P>0.05).1 year later, SVC, FVC, FEV1/FVC and FEV1 in smoking cessation group were higher than in smoking group and there were all statistical significance in the difference (P<0.05). Compared with ex-smoking group and non-smoking group,except FEV1/FVC, other pulmonary function indicators in smoking cessation group were higher while there were not statistical significance in the difference(P>0.05). Compared with ex-smoking group and non-smoking group, the pulmonary function indicators were lower than in the smoking group, except FEV1/FVC, there were not statistical significance in the difference(P<0.05).(2) Comparisons of PEF among the four groups at different follow-up time.PEF in smoking cessation group in the 9th and 12th month were higher than the first test and there were statistical significance in the difference(P<0.05).During the follow-up, PEF in smoking group were decreased than the first test and the declination in the 6th,9th and 12th were significant which had statistical significance in the difference(P<0.05). PEF in ex-smoking group and non-smoking group were lower than the first test while there were not statistical significance in the difference (P>0.05).There were not not statistical significance in the difference (P>0.05). In the 9th and 12th month, PEF were higher in smoking cessation than in smoking group and there were statistical significance in the difference (P<0.05). During follow-up, PEF were lower in smoking group than in ex-smoking group and non-smoking group while there were not statistical significance in the difference (P>0.05).5. Comparisons of the density exhaled carbon monoxide(CO) level and COHb% among the four groups at different follow-up time. In the first test, the density exhaled carbon monoxide(CO) in smoking cesstion group was high but in the 3th,6th,9th and 12th month, which were significantly lower than the first test (P<0.05). The changes of density exhaled carbon monoxide (CO) in Other groups were not significant different(P>0.05).In the first test, the density exhaled carbon monoxide(CO) in smoking cessation group and smoking group were higher than in ex-smoking group and non-smoking group and there were statistical significance in the difference (P<0.05).In the 3th,6th,9th and 12th month, the density exhaled carbon monoxide(CO) in smoking cessation group were signifi-cantly lower than in smoking group(P<0.05) and which in smoking group were higher than in ex-smoking group and non-smoking group (P<0.05).The changes of the COHb% among the four groups were consisitent with the changes of the density exhaled carbon monoxide(CO).6. Comparisons of 6MWD among the four groups in 1 year. After 1 year follow-up, the 6MWD were higher than the first test among the four groups while there were not statistical significance in the difference (P>0.05).While the 6MWD in smoking cessation group was higher than in smoking group and there was statistical significance in the difference (P<0.05).7. Comparisons of BODE scores among the four groups in 1 year. After 1 year follow-up, the BODE scores in smoking cessation group was lower than the first test and there was statistical significance in the difference (P<0.05).While the BODE scores in smoking group was higher than the first test and there was statistical significance in the difference (P<0.05).Compared with the first test,the changes of BODE scores in ex-smoking group and non-smoking group were not significant after 1 year follow-up(P>0.05). In the first test,there were not statistical signifi -cance in the difference (P>0.05) among the four groups.1 year later,the 6MWD among the four groups were not all the same (P<0.05).8. Comparisons of comorbid diseases among the COPD patients. In the 315 studied subjects,110(34.9%) of them had comorbid diseases. Hyperten-sion(49(15.6%)),cardiovascular disease(43(13.7%)) and diabetes (18(5.7%)) were the three most frequent coexisting diseases in COPD patients. Subjects in an older age group (≥60 yrs), BMI≥25.kg·m-2 group,and high risk group(GOLD stage3-4) were not only associated with a higher risk of having hypertension, cardiovascular disease and diabetes,but also associated with a higher risk of having at least two comorbid diseases.Conclusions:1.Medical intervention can improved the smoking cessation rate and male COPD patients were easier to quitting than female COPD patients.2. Smoking cessation can improved the pulmonary function and smoking may accelerate the declination of the pulmonary function.3. After smoking cessation, the density exhaled carbon monoxide(CO) level and COHb% were both significantly lower than before and closed to that in ex-smoking group and non-smoking group.4. Smoking cessation may improved the quality of life in COPD patients.5. The prevalence of comorbid diseases in COPD patients were relatively high.When caring for COPD patients, attentions should be paid to the presence of the comorbid diseases and to do both in order to achieve a better therapeutic effect.