Table 2

Hazard Ratios for First Cardiac Event Age 18 to 40 Years

FactorHazard Ratio95% CIp Value
History of a cardiac event before age 18 yrs
 1 cardiac event (vs. no event)2.431.53–3.87<0.01
 2–10 cardiac events (vs. no event)5.363.64–7.91<0.01
 >10 cardiac events (vs. no event)12.016.93–20.80<0.01
Genotype
 LQT2 vs. LQT12.271.67–3.10<0.01
 LQT3 vs. LQT11.150.63–2.120.65
 LQT2 vs. LQT31.971.08–3.580.03
Gender
 Female (vs. male)3.052.13–4.38<0.01
QTc category
 440–469 ms (vs. ≤439 ms)4.931.18–20.57<0.05
 470–499 ms (vs. ≤439 ms)6.711.63–27.67<0.01
 500–549 ms (vs. ≤439 ms)9.582.33–39.47<0.01
 ≥550 ms (vs. ≤439 ms)10.072.41–42.16<0.01
Time-dependent beta-blocker therapy
 Beta-blockers (vs. no beta-blockers)0.410.27–0.64<0.01

CI = confidence interval; QTc = corrected QT interval.