Analysis of Keshan disease investigation result in Yunnan province in 2008 / 中国地方病学杂志

Objective In order to master the current situation of Keshan disease in Yunnan province and to provide scientific basis for Keshan disease control and prevention. Methods Eighteen villages were selected as the investigation sites in 6 counties across all the Keshan disease wards in Yunnan province,where the residents were investigated. Then,the villages census data was collected,clinical examination aiming mainly on cardiovascular system was carried out,including electrocardiography and X-ray to the suspected patients. Correct diagnose of Keshan disease was made by the Diagnostic Standard of Keshan Disease(GB 17021-1997). At the same time,10 food samples and 10 hair samples for detecting selenium content in every investigation site. Results There were 9818 residents investigated in the 18 investigation sites in 6 counties,and 34 eases of Keshan disease were found,the total incidence rate was 0.35%(34/9818). Among the 34 Keshan disease eases,32 cases were latent Keshan disease,the incidence rate was 0.33%(32/9818); 2 cases were chronic Keshan disease,the incidence rate was 0.02%(2/9818). There was no any acute and sub acute cases be found. Most Keshan disease cases aged from 5 to 14,67.65% (23/34). Abnormal ECG rate was 6.90% (677/9818). Among 56 X-ray films,47 cases had a cardiothoracic ratio less than or equal to 0.50,83.93%(47/56),5 cases from 0.51 to 0.55,8.93%(5/56),4 cases from 0.56 to 0.60,7.14%(4/56). Selenium content was detected in 180 food samples and 180 hair samples. The average food selenium content (mg/kg) was 0.013±0.010,the lowest content in Yongsheng county (0.006± 0.001),the highest content in Tonghai county(0.027±0.009). The average hair selenium eontentwas(0.252± 0.078)mg/kg,with the lowest(0.145±0.043)mg/kg in Yoagsbeng county,the highest (0.297±0.062)mg/kg in Tonghai county. Conclusions The detected ratio of Keshan disease is low in Yunnan province. Most of Keshan disease patients age from 5 to 14. It was presented that the Keshan disease infectious agents were still strong and active. The foodstuffs and hair Selenium content is low in food and hair sample,and varies in different investigation site. It is necessary to supply selenium for prevent Keshan disease in the severe areas.

Analysis of Keshan Disease surveillance data in Yunnan Province in 2007 / 中国地方病学杂志

Objective To study the current incidence of Keshan disease in Yunnan Province,and provide scientific basis for Keshan disease(KD) prevention and control. Methods Based on the Scheme of KD Surveillance, 16 villages in 11 counties were chosen as surveillance sites by the historical data. An survey was made to the residents in the 16 surveillance sites by filling in the questionnaire, inquiry medical history, clinical examination, electrocardiogram and 2 meters post-anterior chest X-ray for suspected cases. KD cases were diagnosed according to the Diagnostic Criteria for Keshan Disease(GB 17021-1997). The prevalence data of KD in the whole province were collected from the KD case report in 2007 and the trace surveys. Results There were 6877 residents in 16 surveillance sites of 11 surveillance counties and totally 39 KD cases were diagnosed with a detection ratio of 0.57% (39/6877). The detection ratio of latent and chronic KD were 0.41%(28/6877) and 0.16%(11/6877), respectively and no acute or subacute cases were found. The cases aged 5 to 14 years old accounting for 66.67% (26/39). Electrocardiogram examination of 6877 residents were made and 5.25% (361/6877) abnormal electrocardiograms were detected in the 16 surveillance sites. Fifty-five people were checked by chest X-ray and there were 31 cases with heart-chest ratio ≤0.50, 16 cases with heart-chest ratio from 0.51 to 0.55 and 8 cases with heart-chest ratio from 0.56 to 0.60. The prevalence rate and incidence rate of chronic KD were 4.24 per 100 000 and 0.50 per 100 000 in Yunnan. No acute or subacute cases were found and the latent cases were listed. The prevalence rate and incidence rate were 7.76 per 100 000 and 1.18 per 100 000 in the 16 surveillance sites. Conclusions The incidence of KD is low incidence in Yunnan Province. Higher ineidence of chronic KD was detected in the some areas and the corresponding control measures need to be adopted.

Clinical features of unexpected sudden death clustered in 7 families in Yunnan Province / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the clinical features of unexpected sudden death (SUD) clustered in families in Yunnan province.</p><p><b>METHODS</b>This retrospective study analyzed the clinical features of SUD occurred between July to September 2005 in 7 families in Yunnan province.</p><p><b>RESULTS</b>All 16 SUD patients shared common clinical features such as fatigue and repeated syncope and one group of SUD patients (n = 8 from 4 families) presented with the gastric intestinal tract manifestations including nausea, vomiting, abdominal pain and diarrhea with suspected dietary history and abnormal laboratory enzyme findings (GOT/GPT, CK/CKMB, LDH/LDH1 etc.). In SUD patients without gastric intestinal tract manifestations (n = 8 from 3 families), there were no clear symptoms before death and repeated ventricular tachycardia and ventricular fibrillation were recorded in one survivor. There was no clear evidence for the involvements of hereditary and infectious factors for observed SUD.</p><p><b>CONCLUSION</b>The reason for the unexpected sudden death clustered in 7 families in Yunnan remains unclear. Repeated syncope and fatigue served as the common clinical features in the presence or absence of gastric intestinal tract manifestations in all SUD cases. Further studies are needed to clarify the pathology and detailed clinical manifestations of SUD occurred in this area.</p>

Investigation and analysis on the incidence of "Yunnan unknown-cause sudden cardiac death" during / 中华流行病学杂志

<p><b>OBJECTIVE</b>To understand the epidemiologic and clinical characteristics of the "Yunnan unknown-cause sudden cardiac death (YUSCD)".</p><p><b>METHODS</b>Cases of YUSCD occurred in 2002-2004 were investigated with cross-sectional study. Clinical manifestation was observed and analyzed.</p><p><b>RESULTS</b>The YUSCD areas were mountainous and most of the YUSCD cases appeared between June and August. Most of the YUSCD cases were young farmers and showed family/village clustering nature. Most of the patients died quickly with only few recovered. The overall incidence of YUSCD was 1.83% with mortality as 1.51%. The fatality rate of YUSCD appeared to be 78.1%.</p><p><b>CONCLUSION</b>The YUSCD cases had a clustering feature along with time and area. The clinical manifestation of YUSCD could not be specifically identified, making the clinical diagnosis and treatment difficult when practicing in the fields that called for further studies on epidemiology, clinical work and etiology.</p>

Morphologic features of sudden cardiac death in Yunnan province, with emphasis on myocarditis / 中华病理学杂志

<p><b>OBJECTIVES</b>To study the pathologic feature of sudden cardiac death in Yunnan province and to investigate the role of myocarditis.</p><p><b>METHODS</b>During the period from 1991 to 2006, there were 29 cases of sudden cardiac death with autopsy performed. Fourteen of these cases were diagnosed to have myocarditis based on Dallas criteria and World Heart Federation's consensus. The clinical and pathologic findings were reviewed. The cardiac conduction system was examined in details by serial sectioning in 3 cases.</p><p><b>RESULTS</b>Fourteen cases suffered with myocarditis, which accounted for 48% of all cases of sudden cardiac death studied. The age of the deceased ranged from 8 to 68 years (mean = 30 years), with male-to-female ratio equaled to 9:5. Lymphocytic myocarditis and neutrophil myocarditis were the two major types, affecting 11 and 3 cases, respectively. The inflammatory infiltrates were often patchy rather than diffuse. The inflammatory foci were detected only in 8% to 42% (average = 20%) of the paraffin sections of the heart tissue. These lesions were usually located in the lateral wall of left ventricle and occasionally in interventricular septum and right ventricular wall. Myocardial injury was mild in most cases while patchy myocytolysis or coagulation necrosis was observed only in a few cases. Most of the lesions were relatively new and histologic evidence of myocardial repairing sometimes coexisted. Pericarditis and subacute endocarditis were also identified in 4 and 1 cases, respectively. Atrioventricular node was involved by myocarditis in 1 of the 3 cases examined for cardiac conduction system. Two cases showed gross evidence of cardiac dilatation (either left ventricle or biventricular). Respiratory tract and pulmonary infection was present in 5 cases.</p><p><b>CONCLUSIONS</b>Myocarditis represents one of the major pathologic changes of sudden cardiac death occurring in Yunnan province. The inflammation is usually focal. Further studies are required for delineation of possible etiologies which may include virus, bacteria or exogenous toxin.</p>

Retrospective study on 116 unexpected sudden cardiac deaths in Yunnan, China / 中华流行病学杂志

<p><b>OBJECTIVE</b>To identify the epidemiological and clinical features of unexpected sudden cardiac deaths (SUD) in Yunnan.</p><p><b>METHODS</b>Choosing the old SUD cases from Xiangyun, Heqing, Nanjian and Dayao counties and using the standardized verbal autopsy Form, we interviewed the family members of the cases, witnesses and doctors as well as reviewing their medical files to get relative information.</p><p><b>RESULTS</b>We identified 116 SUDs in 21 villages from 1984 to 2004. The village-specific annually standardized incidence rates were ranged from 0.2/1000 to 8.9/1000 (median = 0.8/1000). 66% and 29% of the SUDs occurred in July and August respectively. The incidence rates of SUD were higher (1.6/1000, chi(2) = 16, P < 0.01) in 10 - 39 year-olds, and higher in females than in males (RR = 1.6, 95% CI: 1.1 - 2.3). Seventy percent of SUD occurred in families having clustering nature and 60% of the additional cases in the family were occurred within 24 hours (median = 20 hours) after the first SUD identified in the family. SUD occurred in 23 families followed the first affected family in a village during the same season. In these 23 families, 61% of the first SUD occurred within 8 days after the first SUD in the first affected family. 68% and 66% of the SUDs did not have any complaints or signs during the last 3 weeks or from 3 weeks to 2 days prior to the onset of the disease. 63% of the SUDs had cardiac symptoms within the last 2 days prior to the onset with major symptoms as dizziness, nausea, faintness, unconsciousness, weakness and palpitation. The median duration from acute onset to death was 2 hours.</p><p><b>CONCLUSIONS</b>The extreme time-space clustering of SUD in families and in villages suggested that the risk factors occurred in specific time and location. Familial clustered SUD cases had common exposure pattern. Sudden onset of acute cardiac symptoms often followed by sudden death. Epidemiological study on new cases was necessary to identify risk factors and to develop hypothesis for causation. In July 2005, we instituted a special SUD surveillance system for all the affected counties together with 10 counties which had no reported cases.</p>