The Establishment Of Dynamic Monitoring And Symptom Perception Model In Asthmatic Patients

The current asthma guidelines encourage use of a diary of assessing and monitoring symptoms and airway function. However, the compliance with the diary and the accuracy of the monitoring are the guarantee of clinical value. Inaccurate symptom perception has long been noticed in asthma patients, but never has a clear definition, factors affect asthma symptom perception remain unsolved.This study consists of four sections. The method of symptom-lung function monitoring was established in the first and the second section. The third section was about it's clinical value. The last section was the construction of asthma symptom perception model, identifying patients in the model, and discussing possible factors influencing symptom perception.In the first chapter,106 asthmatic patients were recruited into the compliance study, who underwent a fixed-time thrice-daily assessment schedule for a period lasting two weeks. Symptoms and medication use were recorded in a booklet (paper diary), and airway function measured by a portable spirometer (electronic diary). Patient compliance with paper diary was significantly lower than that of electronic diary (72% of paper diary vs.80% of electronic diary). The lower compliance with paper diary was particularly due to the uncertain compliance observed in paper diary entries (12%), which were unable to be verified by the electronic record of the date and time of the entry. A significant difference was found in different recording time, the highest compliance was obtained in the evening, whereas the lowest was in the early morning. Patient compliance fell in the second week, as compared to the first week of diary keeping. Among demographics and clinical factors, age, gender, education level and asthma severity were not found to be related to patient compliance with diary keeping. Patients with high anxiety level were less compliant with diary keeping, as compared with patients with lower anxiety level. In the second chapter, the accuracy of unsupervised spirometry manoeuvre in asthmatic patients was discussed.128 patients finished 4249 compliant spirometry tests.95% manoeuvres were acceptable, and 74% met the four criteria of strict accuracy, in terms of "F-V curve acceptability+ BEV＜150ml+FEV1 reproducibility＜200ml+FVC reproducibility＜200ml".28% manoeuvres had the FET≥6s, and 48% FET was between 3-6s. Better reproducibility was obtained in the afternoon and evening, which was the same in the second week. FEV1 reproducibility was better in the patients who were under 40 years and who had college and above education. Patients with lower STAI-State score had better acceptability in spirometry tests. Lower FVC reproducibility was accompanied by higher PEF variability.Chapter 3 evaluated the specificity in diagnosis and differential diagnosis of dynamic assessment and monitoring in asthma patients, which may have the advantage of capturing diurnal changes of airway function. Of 145 patients with physician-diagnosed asthma,126 (87%) could be conclusively confirmed for a diagnosis of asthma. Asthma was misdiagnosed in 14 patients (9.5%). Overdiagnosis of asthma was observed in 5 patients (3.5%). It was concluded that dynamic assessment and monitoring using a portable spirometer by revealing variability and reversibility of airway obstruction may provide an additional tool for diagnosis and differential diagnosis of asthma.Chapter 4 was the establishment of asthma symptom perception model.100 asthmatic patients finished more than 30 dynamic symptom-lung function data points in 14 days were recruited into the study. Symptom perception zones were plotting out according to the symptom score-FEV,%Predicted relationship, thus patients were classified as normal-perception, under-perception and over-perception with the percentage of 54%,32% and 14% respectively. Normal-perception patients had a small part of monitoring in over-perception or under-perception zones, but over-perception and under-perception wouldn't be in the same patient. Patients had more accurate perception in the afternoon, and inaccurate perception in the evening. Males had a quarter under-perception more than females. Over-perception was associated with high anxiety level. Asthma severity affected symptom perception in terms of PEF variability. Patients with PEF variability between 20%～30% had 73% normal-perception records, however the normal-perception records decreased to 50% in patients with PEF variability more than 30%, the latter had 43% under-perception records, which was much higher than mild and moderate asthma patients.In conclusion, the study evaluated the dynamic monitoring method in asthma patients, established a symptom perception model, and discussed the possible influential factors.