Framingham Risk Score Is an Ineffective Screening Strategy for Coronary Heart Disease in Long-Term Allogeneic Hematopoietic Cell Transplant Survivors.

Abstract

Long-term allogeneic hematopoietic cell transplant (allo-HCT) survivors suffer an elevated risk of coronary heart disease (CHD). We conducted a prospective, nonrandomized, cross-sectional study to screen asymptomatic survivors at a single allo-HCT center using cardiac computed tomography (CT) involving coronary CT angiography (CCTA) and the coronary artery calcium (CAC) score. Seventy-nine subjects with a median age of 39 years at allo-HCT and a median follow-up interval of 8 years were evaluated for CHD by Framingham Risk Score (FRS) and cardiac CT. CHD was detected in 33 of 79 (42%) subjects; 91% of lesions were nonobstructive, 19.5% of were noncalcified and 30% had associated valvular calcification. Overall, CAC was significantly superior to FRS in detecting early CHD in allo-HCT survivors [∆C = 0.25; P < 0.0001]. While both FRS and CAC were highly, >95% specific, FRS had a sensitivity, positive and negative predictive values of only 28% (95% CI, 14%-47%), 90% (95% CI, 55%-100%) and 60% (95% CI, 47%-73%), respectively. In contrast, the sensitivity, positive and negative predictive values of CAC were 78% (95% CI, 60%-91%), 96% (95% CI, 80%-100%) and 83% (95% CI, 69%-93%), respectively. Significantly, cardiac CT detected CHD in 23 of the 68 (34%) survivors deemed to have a low Framingham risk. Radiation exposure during cardiac CT was negligible, and there were no adverse events. In conclusion, CAC score with or without CCTA is a safe, feasible and sensitive screening technique for CHD. The FRS greatly underestimates CHD in allo-HCT survivors.