Moyamoya syndrome may be predicted by heightened blood pressure in those with Down syndrome, according to a study recently published in Pediatrics. This could serve as a simple prognostic tool in risk assessments among individuals with Down syndrome.
This case-control, retrospective, single-center study included 116 individuals with Down syndrome (control group) and 30 with both Down syndrome and Moyamoya syndrome. Blood pressure recordings taken 6 to 12 months, 12 to 18 months, and 18 to 24 months before moyamoya syndrome diagnosis were examined and compared with values from the control group. Researchers utilized the Mann-Whitney U test to contrast blood pressure percentiles between groups. They also used a general linear model to investigate changes with time and a generalized multivariable analysis to distinguish predictors of both Down syndrome and moyamoya syndrome.
Among patients with both disorders, blood pressure showed a significant increase during the 2-year period before presentation; at 6 to 12 months, blood pressure was in the 70th percentile; at 12 to 18 months, in the 42nd percentile; and at 18 to 24 months, in the 34th percentile. By comparison, the control group’s blood pressure percentiles remained relatively stable throughout these intervals. Additionally, individuals with both disorders had significantly higher blood pressure levels than those with Down syndrome alone only during the 6- to 12-month (P <.001) and 12- to 18-month (P =.016) periods preceding presentation. Higher blood pressure was predicted by higher posterior circulation involvement and bilateral disease. Another predictor was higher Suzuki scores, which correlated in the intervals from 6 to 12 months (P <.001) and from 12 to 18 months (P =.005).
“Elevated blood pressure in individuals with Down syndrome may foreshadow symptomatic Moyamoya syndrome and could be a simple, cost-effective screening tool for early identification in this at-risk population,” the researchers said. “Early identification of individuals with Down syndrome who are at risk for the development of moyamoya syndrome may result in better long-term outcomes for this population and can be performed with ease in the pediatric medical home.”
Santoro JD, Lee S, Mlynash M, et al. Blood pressure elevation and risk of moyamoya syndrome in patients with trisomy 21 [published online September 6, 2018]. Pediatrics. doi: 10.1542/peds.2018-0840