Mortality among persons with a history of Kawasaki disease in Japan: can paediatricians safely discontinue follow-up of children with a history of the disease but without cardiac sequelae?
OBJECTIVE
To clarify the question of whether patients with Kawasaki disease suffer a higher mortality rate after the incidence of the disease in comparison with age-matched healthy individuals.


METHODS
Between July 1982 and December 1992, 52 collaborating hospitals collected data on all patients having a new, definite diagnosis of Kawasaki disease. Patients were followed up until 31 December 2001 or their death. The expected number of deaths was calculated from Japanese vital statistics data and compared with the observed number.


RESULTS
Of 6576 patients enrolled, 29 (20 males and 9 females) died. The standardized mortality ratio (SMR: the observed number of deaths divided by the expected number of deaths based on the vital statistics in Japan) was 1.15 (95% CI: 0.77-1.66). In spite of the high SMRs during the acute phase, the mortality rate was not high after the acute phase for the entire group of patients. Although the SMR after the acute phase was 0.75 for those without cardiac sequelae, six males (but none of the females) with cardiac sequelae died during this period; and the SMR for the male group with cardiac sequelae was 1.95 (95% CI: 0.71-4.25). The mortality from congenital anomalies of the circulatory system was elevated, but no increase in cancer deaths was observed.


CONCLUSIONS
Although it was not statistically significant, the mortality rate among males with cardiac sequelae due to Kawasaki disease appeared to be higher than in the general population. On the other hand, the mortality rates for females with the sequelae and both males and females without sequelae were not elevated.
Nakamura
Yosikazu
Y
Department of Public Health, Jichi Medical School, Minamikawachi, Tochigi, Japan. nakamuyk@jichi.ac.jp
Aso
Eiko
E
Yashiro
Mayumi
M
Uehara
Ritei
R
Watanabe
Makoto
M
Tajimi
Morihiro
M
Oki
Izumi
I
Ojima
Toshiyuki
T
Yanagawa
Hiroshi
H
Kawasaki
Tomisaku
T
D002648:Child; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D006331:Heart Diseases / Q000150:complications; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007564:Japan / Q000453:epidemiology; D008297:Male; D009080:Mucocutaneous Lymph Node Syndrome / Q000150:complications / Q000401:mortality*; D011379:Prognosis; D012737:Sex Factors