title: Net survival after exposure to polychlorinated biphenyls and dioxins: the Yusho study.
abstract: BACKGROUND
  Net survival is an important measure of the overall outcome of disease management. This net survival is the most appropriate for international comparisons of disease impact between countries or time periods with different patterns of all-cause mortality because it is not influenced by other causes of death. However, little information is available on net survival among Yusho patients, who were accidentally exposed to PCBs and other dioxin-related compounds.
  
  
  METHODS
  We estimated the net survival of 1664 Yusho patients (860 males, 804 females) as Yusho cohort subjects using the unbiased Pohar-Perme method.
  
  
  RESULTS
  Among males, 1-, 5-, 10-, and 15-year net survival were 99.5% (95% confidence interval (CI): 97.9, 99.9), 99.1% (CI: 95.0, 99.9), 97.4% (CI: 86.5, 99.5), and 97.4% (CI: 84.2, 99.6), respectively. Among females, net survival remained almost constant. 1-, 5-, 10-, and 15-year net survival were generally higher in females than in males.
  
  
  CONCLUSIONS
  This study provides the first unbiased estimations of net survival among Yusho patients. We confirmed that older male Yusho patients have experienced a significant decrease in net survival. Our results suggest that the excess hazard of PCBs and dioxins must be taken into account when evaluating unbiased estimates of net survival.
authors.affiliation: Department of Health Care Administration and Management, Kyushu University Graduate School of Medical Sciences, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan; Fukuoka Institute of Health and Environmental Sciences, 39 Mukaizano, Dazaifu-shi, Fukuoka 818-0135, Japan. Electronic address: onozukad@hcam.med.kyushu-u.ac.jp.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Onozuka
authors.affiliation: Fukuoka Institute of Health and Environmental Sciences, 39 Mukaizano, Dazaifu-shi, Fukuoka 818-0135, Japan.
authors.forename: Teruaki
authors.initials: T
authors.lastname: Hirata
authors.affiliation: Department of Dermatology, Kyushu University Graduate School of Medical Sciences, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
authors.forename: Masutaka
authors.initials: M
authors.lastname: Furue
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D004147:Dioxins / Q000633:toxicity*; D004781:Environmental Exposure / Q000009:adverse effects*; D004785:Environmental Pollutants / Q000633:toxicity*; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D011078:Polychlorinated Biphenyls / Q000633:toxicity*; D011164:Porphyrias / Q000401:mortality*; D016019:Survival Analysis; D055815:Young Adult
chemical_list: D004147:Dioxins; D004785:Environmental Pollutants; D011078:Polychlorinated Biphenyls
keywords: Cohort study; Dioxins; Food contamination; Net survival; Polychlorinated biphenyls; Yusho