背景
全球自閉症患者的盛行率逐漸增加，然而，關於患者死亡的資訊卻相當有限。本研究利用存活分析及外推計算方法，推估自閉症兒童之預期壽命及預期損失壽命。
方法
選取1998至2009間的全民健康保險資料進行分析，選出7192位年齡小於18歲之自閉症兒童，利用13年的追蹤資料進行存活分析。使用Cox多變量比例風險模式控制性別、診斷年齡、癲癇、智能障礙等干擾因子，探討對自閉症患者存活風險之影響。利用存活函數外推80年估計預期壽命，並與性別、年齡相配對之參考族群做比較估計預期損失壽命。
結果
相較於0到5歲間診斷之病童，6到11歲間診斷之病童之調整後死亡危險增加2.46倍 (95% 信賴區間, 1.11-5.46)，12到17歲間診斷之病童之調整後死亡危險升高至7.56倍 (95% 信賴區間, 3.63-15.74)。癲癇會顯著顯著增加自閉症死亡危險(調整後風險比, 3.12; 95% 信賴區間, 1.84-5.28)，性別與智能障礙則無此相關性。男性患者預期壽命為30.7(±12.2)歲，女性患者預期壽命則為43.2 (±17.3)歲。在學齡前診斷的自閉症兒童與其性別年齡配對的一般兒童有相同的預期壽命。藉著世代效應的檢查證實了這個推論。最常見的死因為癲癇與非疾病死亡。
結論
自閉症的診斷年齡及是否併有癲癇是影響死亡風險的決定因子。早期診斷幫助自閉症獲得較好的存活。

Background
The prevalence of autism spectrum disorder is increasing worldwide, however, the mortality information is limited. We performed survival analysis, explored the determinants of survival and estimated the life expectancy and expected years of life lost for children with autism.
Method
Using the National Health Insurance data between 1998 and 2009, we identified a cohort of 7192 individuals with newly diagnosed autism younger than 18 years of age and performed survival analysis with 13 years of follow-up. Multivariable Cox proportional-hazards model were constructed to assess the effect of sex, age at diagnosis, epilepsy and intellectual disability on survival,. Life expectancy was estimated by the 80-year extrapolation of the survival function with the information of an age- and sex-matched reference population.
Result
The adjusted hazard ratio of mortality of 6-11 years of age at diagnosis was 2.46 (95% CI, 1.11-5.46) and that of 12-17 years of age at diagnosis was 7.56 (95% CI, 3.63-15.74) as compared with that of 0-5 years of age at diagnosis. Epilepsy significantly increased the risk of mortality (adjusted hazard ratio, 3.12; 95% CI, 1.84-5.28) while female sex and intellectual disability did not. The average life expectancy of male was 30.7(±12.2) years and that of female was 43.2 (±17.3) years. Children with autism diagnosed during 0-5 years old had no significant difference in life expectancy as compared with the age- and sex- matched reference population. Examination for cohort effect corroborates the inference. Epilepsy and external causes were the most common causes of death.
Conclusion
Age at diagnosis and epilepsy were predictors of mortality of autism. The earlier the children received the ASD diagnosis, the better they would survive.

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