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>

A field epidemiological study on the risk factors of injury caused by typhoon / 中华流行病学杂志

<p><b>OBJECTIVE</b>To determine the risk factors involved in the typhoon episodes and to put forward and evaluate the intervention measures.</p><p><b>METHODS</b>We defined a confirmed injury case as: 'a person with fall,scalpel and stab, collision, drowning, injuries and trauma due to flying debris and building collapse, asphyxiation due to entrapment in collapsed buildings by typhoon from 0 am,August 12 to 6 pm, August 14 2004' and a death case as: 'a person with fall, scalpel and stab, collision, drowning, injuries and trauma due to flying debris and building collapse, asphyxiation due to entrapment in collapsed buildings by typhoon from 0 am, August 12 to 12 am, August 18 2004'. We investigated all hospitalized injured cases in ten hospitals and telephoned to those who were not hospitalized and the cases of death. We did case-control study with 1 pair versus 2 cases. 74 cases were selected in ten hospitals. The controls were neighbors of the controls matched by occupation, sex, village, and within 5 years of age without injury in this typhoon. We asked the cases and the controls on their alertness regarding typhoon and what actions taken when typhoon arrived.</p><p><b>RESULTS</b>There were 392 injury cases in all ten hospitals and 50 death cases. The attack rate of injury was 27.3 per 100 000. The fatal rate was 11.3% with the death rate 3.1 per 100 000. We investigated 209 injury cases and 31 death cases. The number of cases who were injured from 1 to 6 hours before typhoon landing accounted for 64.6% (155) of all cases. The peak of epidemic curve was 4 hours before the landing of typhoon. Data on the analysis of 74 cases and 148 controls revealed that 42% (31) of the cases were outside their homes before and during typhoon compared to 15% (22) of the controls (OR = 3.9, 95% CI: 1.9-7.7). Compared with 20% (30) control persons (OR = 17,95% CI: 4.2-68). 28% (21) cases did not receive the alert of typhoon before it arrived compared with 18% (27) control persons (OR = 3.3, 95% CI:1.3-8.6). 53% (39) of the cases did not pay attention to the alert of typhoon before typhoon arrived.</p><p><b>CONCLUSION</b>Staying outdoor, not receiving or did not take seriously about the alert of typhoon seemed to be the risk factors of injury by the typhoon episode, suggesting that the government should increase the emergency preparedness and to raise the awareness on risks associated with typhoon.</p>