Human Serum Amyloid A Protein Level In Patients With Chronic Obstructive Pulmonary Disease And Its Clinical Significance

Objectives:The pathogenesis of chronic obstructive pulmonary disease（COPD）is not fully clear at present,which may be related to inflammatory response,protease/antiprotease imbalance,oxidative stress,but remaining inconclusive.The diagnosis of COPD is mainly through the patient symptom and measuring the lung function,but the value of lung function measurement is easily influenced by factors such as patient cooperation and the attitude of the medical staff.so the lung function measurement has certain limitations.It is significant to find a simple and easy-to-measure biological indicator which can reflect the prognosis.For this study,SAA concentration in patients with COPD,AECOPD after and before the treatment,and healthy subjects are measured,and the SAA concentration is used for the correlation analysis with the Forced Expiratory Volume in one second（FEV₁）/Forced Vital Capacity（FVC）,and FEV₁ accounting of predicted value（FEV₁%pred）.The times of acute exacerbation for the patients with high and low SAA high concentration are compared through follow-up within 6 months,which is aiming to investigate if there is any difference in the SAA concentration in different groups.If there is,the purpose is to find the difference is statistically significant or not,to explore the relationship between SAA and COPD,to assess the severity of COPD patients and prognosis,to provide a new methodological reference for the COPD assessment.Method:Patients with COPD who were admitted to the Department of Respiratory Medicine and Inpatient Department of the Affiliated Hospital of North Sichuan Medical College from October 2017 to May 2018 are selected as subjects.42 of them are in the COPD stable phase group（SCOPD group）,including 22 males and 20 females,aged 50-85,with an average age of（68.14±8.21）.48 of them are suffering from AECOPD,including 28 males and 20 females,aged 57-82,with an average age of（72.38±8.34）,which of them are 30 control patients before and after treatment,23 males and 7females,aged 52-81,with an average age of（71.46±8.25）.The AECOPD patients were treated with anti-infective,antispasmodic,anti-tussive,expectorant,and oxygen-absorbing symptomatic support treatment for 1-2weeks after admission.After the patient coughed and exercised,the shortness of breath is significantly improved,and the hemogram returned to normal,meaning the patients are in stable condition.The SCOPD group is divided into low and high concentration group according to the median of serum SAA concentration,21 of them in low-concentration group,including 12 males and9 females,with an average age of（72.54±8.17）,and 21 of them in high-concentration group,including 10 males and 11 females,with an average age of（71.93±8.23）.The patients were followed up for the times of acute exacerbation from July 20 to December 2018.The physical examination subjects at the Medical Center of the Affiliated Hospital of North Sichuan Medical College from October 2017 to May 2018 are selected as the control group,and there are 40 subjects,including 20 males and 20 females,aged58-85,with an average age of（72.88±8.21）.The serum SAA concentration is measured,and the difference of SAA concentration in different groups is compared and analyzed.The relationship between SAA and FEV₁ and FEV₁%pred is analyzed,which is compared with the times of acute exacerbation for the patients with high and low SAA concentration within 6 months,to show if there is any difference.Results:（1）The SAA concentration in the AECOPD group is746.75±92.61mg/L,which is higher than 692.36±69.27mg/L in the SCOPD group and 239.17±65.20mg/L in the control group,showing statistically significant difference（P<0.01）.The SAA concentration in the SCOPD group is higher than that in the control group,showing statistically significant difference（P<0.01）.（2）The SAA concentration in the AECOPD group is762.93±84.93 mg/L,which is higher than 701.77±77.00mg/L after treatment,showing statistically significant difference（P<0.01）.（3）The SAA concentration in the SCOPD group is negatively correlated with FEV₁%pred and FEV₁/FVC,and the correlation is statistically significant（r=-0.53P<0.01;r=-0.70 P<0.01）.（4）The times of acute exacerbation in the high-concentration group is higher than that in the low-concentration group within 6 months,showing statistically significant difference（P<0.05）.Conclusions:（1）Compared with the healthy control group,the SAA of the patients in the SCOPD and AECOPD group increased,and the SAA of the patients in AECOPD group increased significantly,which decreased after treatment.It is speculated that SAA is involved in the development of COPD.（2）The SAA of SCOPD group patients is negatively correlated with FEV₁%pred and FEV₁/FVC,showing that the higher the SAA value,the more severe the lung function damage,which indicates that SAA can be used as a reference index to reflect the severity.（3）Based on the 6-month follow-up,the times of acute exacerbation for patients with high SAA concentration were found to be higher than that of the patients with low concentration within 6 months.This may be because SAA is involved in the development of inflammation,and SAA may become a new indicator for the prognosis of patients.