Study On Epidemiological Feature And Risk Factors Of Bronchial Asthma

Objective Bronchial asthma (BA) is a common chronic disease of air way. It was said that the incidence and mortality rate were increasing in the recent ten years. The number of sufferers was about 150,000,000. It led to the greater society burden and economy loss than tuberculosis and AIDS , and became the attention problem in commonality sanitation. Epidemiology research showed that the incidence rate was 0.1%～32% in the world and 1%～6.9% in some areas of our country. Li people form an unique ethnic group and reside in Hainan Province. But it is unavailable in Li people. We carry the research in order to prevent and cure it, know the epidemiological feature and risk-factors, and discuss the relation between bronchial asthma and platelet-activating factor acetylhydrolase(PAF-AH). Methods 1)To investigate the prevalence of BA in Li people, to know the epidemiology feature and to identify the risk factors of BA using stratified randomized program by clustering sampling for BA. This study was carried out in 2097 Li people in Hainan province according to symptoms using BA criteria. All subjects were investigated by questionnaire during visiting to them. Potential risk factors were investigated between BA and non-BA group using logistic analysis of multi-factors. 2) To discuss the relation between BA and PAF-AH using group-suited case-case control study. Results 1) The prevalence of BA was 3.0% in Li people, 2.3% and 5.0% in south and middle of Hainan province, 3.2% and 2.7% in the male and female group, respectively. The prevalence of BA in the group of less than 18 years and more than 60 years was higher in all ages. The multivariable analysis showed risk factors were family history (OR=48.281, OR95%CI= 4.839-481.719, P =0.001), abnormal emotion(OR=0.778, OR95%CI=0.592-1.023, P =0.072) and life quality(OR=0.676, OR95%CI=0.514-0.890, P =0.005). 2) There were no significant different in the frequency of genotype mutation and allele mutation in cases and controls (χ2=0.904/1.431,P =0.342/ 0.232). Plasma PAF-AH activities of paroxysm group were 11.86±5.62μmol/(min·L)and lower than those of recover group and control group, which were 29.75±7.43μmol(/min·L)and 31.62±6.19μmol(/min·L), respectively. In control group and recover group plasma PAF-AH activities of Val/Val genotype were 32.38±5.65μmol(/min·L)and 31.67±5.95μmol(/min·L). Val/Phe genotype were 20.90±1.60μmol(/min·L)and 17.62±2.16μmol/(min·L). There was significant different of plasma PAF-AH activity between two groups of genotypes (Val/Val,Val/Phe,) in either control group or recover group. In the similar genotype, there was no significant different of plasma PAF-AH activity between the groups of control and recover. Conclusion 1)The prevalence of BA was 3.0% in Li people, and it is about 2.17 times in middle to south. There is no significant different between male and female in the incidence rate. Family history, abnormal emotion and life quality play an important role for the pathophysiology of the BA. 2) There were no significant different in the frequency of mutation genotype and mutation allele in cases and controls. Plasma PAF-AH activities of paroxysm group were lower than those of recover group and control group. PAF-AH gene mutation was related with plasma PAF-AH activity.