A cohort study of 1425 persons with Down's syndrome (DS), and of their parents (447 mothers, 435 fathers) and siblings (1176), was set up to investigate death rates from various causes and cancer incidence patterns. In individuals with DS the all-cause death rate was six times that of the national population (SMR = 622: 95% CI 559-693), the excess being attributable to many different causes. These included: leukaemia (SMR = 1304: 95% CI 651-2334); diabetes mellitus (SMR = 982: 95% CI 267-2515); Alzheimer's disease (SMR = 22028: 95% CI 7137-51326); epilepsy (SMR = 1727: 95% CI 744-3403); and congenital anomalies (SMR = 4987: 95% CI 4175-5955). The overall survival showed marked improvements for successive birth cohorts, particularly at young ages. For mothers and fathers of persons with DS, all-cause death rates were 20% lower than national rates and there were no significant excesses from any specific cause. For siblings, all-cause death rates were similar to national rates; the only condition with a significantly raised mortality ratio was colo-rectal cancer (SMR = 793: 95% CI 216-2031), but this may well be a chance finding.

Original publication

DOI

10.1017/S0003480001008508

Type

Journal article

Journal

Ann Hum Genet

Publication Date

03/2001

Volume

65

Pages

167 - 176

Keywords

Adolescent, Adult, Aged, Bias (Epidemiology), Cause of Death, Child, Child, Preschool, Cohort Studies, Down Syndrome, England, Female, Humans, Infant, Infant, Newborn, Male, Middle Aged, Neoplasms, Nuclear Family, Parents, Scotland