More children died on the highest sildenafil dose, unexplained
Among 234 children treated for raised pressure in the lung arteries, three-year survival was 94% on low-dose sildenafil, 93% on medium and 88% on high. Every group still beat historical expectation.
What the study found
Children on the highest dose died at four times the lowest-dose rate
Among 234 children treated for raised pressure in the lung arteries, three-year survival was 94% on low-dose sildenafil, 93% on medium and 88% on high: a hazard ratio of 3.95, highest against lowest. The investigators could not explain it, and every group still beat historical expectation.
The caveat · Dose groups did not start alike
This was an extension study, not the randomised trial: children carried their original dose assignment forward while former placebo recipients were newly randomised, so the groups did not start alike. Those who died were far likelier to have the severe inherited forms and worse baseline function.
What we don't know
In a long-term follow-up, children on the highest sildenafil dose died at nearly four times the lowest-dose rate. Whether dose caused it is open: the groups did not start alike, and the sickest children were over-represented among deaths.