Rett syndrome in Australia: a review of the epidemiology.
OBJECTIVE
To examine the prevalence, cumulative incidence, and survival in an Australian cohort with Rett syndrome (RTT).


METHODS
The Australian Rett Syndrome Database is a longitudinal data collection that included 276 verified female cases at the end of 2004. Survival was calculated using the Kaplan-Meier product limit method, and cumulative incidence was determined using the complement of the Kaplan-Meier method.


RESULTS
Most cases (88.4%) have had MECP2 mutation testing, with positive results in 73%. The prevalence of RTT was .88 per 10,000 females in 5- to 18-year-olds, and the cumulative incidence was 1.09 per 10,000 females by 12 years of age. The cumulative incidence by the age of 5 years increased from .39 per 10,000 in the 1980 to 1984 cohort to .76 per 10,000 in birth cohorts beyond 1984. Survival was 77.8% at 25 years, compared with 99.96% survival in the Australian female population. Pneumonia (10/25) was the most common cause of death.


CONCLUSIONS
The availability of genetic testing has contributed to the changing pattern and timing of RTT diagnosis in Australia. Girls with RTT have worse survival compared with the general female population. When more data are available, it will be possible to evaluate the relationship between survival and specific MECP2 mutations.
Laurvick
Crystal L
CL
Telethon Institute for Child Health Research, Centre for Child Health Research, The University of Western Australia, Perth.
de Klerk
Nicholas
N
Bower
Carol
C
Christodoulou
John
J
Ravine
David
D
Ellaway
Carolyn
C
Williamson
Sarah
S
Leonard
Helen
H
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D001237:Asphyxia / Q000401:mortality; D001315:Australia / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D019992:Databases as Topic; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D009154:Mutation; D011014:Pneumonia / Q000401:mortality; D015995:Prevalence; D012131:Respiratory Insufficiency / Q000401:mortality; D015518:Rett Syndrome / Q000453:epidemiology* / Q000235:genetics