Table 2.

Overall and joint association of QTc and CKD with all-cause and cardiovascular mortality

All-cause mortality				Cardiovascular mortality
	Normal QTc	Prolonged QTc	Overall		Normal QTc	Prolonged QTc	Overall
Model 1				Model 1
No CKD	Reference	1.7 (1.4–2.1)	Reference	No CKD	Reference	1.6 (1.2–2.1)	Reference
CKD by eGFR only	1.5 (1.2–1.8)	2.6 (1.7–3.9)	1.5 (1.3–1.8)	CKD by eGFR only	1.8 (1.4–2.2)	3.1 (1.7–5.5)	1.8 (1.4–2.2)
CKD by ACR only	2.0 (1.7–2.3)	2.0 (1.4–3.0)	1.9 (1.7–2.2)	CKD by ACR only	2.4 (1.7–3.3)	2.3 (1.4–3.9)	2.1 (1.6–2.8)
Overall	Reference	1.5 (1.3–1.8)		Overall	Reference	1.4 (1.1–1.8)
Model 2				Model 2
No CKD	Reference	1.6 (1.3–1.9)	Reference	No CKD	Reference	1.5 (1.1–1.9)	Reference
CKD by eGFR only	1.4 (1.1–1.7)	2.6 (1.7–3.9)	1.4 (1.2–1.7)	CKD by eGFR only	1.7 (1.3–2.1)	3.1 (1.7–5.4)	1.7 (1.3–2.1)
CKD by ACR only	1.9 (1.6–2.2)	1.8 (1.2–2.6)	1.8 (1.5–2.0)	CKD by ACR only	2.2 (1.5–3.1)	1.9 (1.2–3.2)	2.0 (1.5–2.6)
Overall	Reference	1.4 (1.2–1.7)		Overall	Reference	1.3 (1.0–1.7)

Model 1 adjusted for age, race, gender, income and educational status.

Model 2 further adjusted for diabetes, hypertension, history of cardiovascular disease, smoking, alcohol, total cholesterol, serum potassium, serum calcium, QT-prolonging medications and beta-blockers use.

Interaction p value from the fully adjusted model: prolonged QTc × CKD by eGFR=not significant, QT × CKD by ACR=not significant for all-cause and cardiovascular mortality.

Net reclassification index from the fully adjusted model adding QTc to CKD. NRI was 0.166, p<0.00001 for all-cause mortality and NRI 0.162, p<0.00001 for CV mortality.

ACR, albumin to creatinine ratio; CKD, chronic kidney disease; CVD, cardiovascular disease; eGFR, estimated glomerular filtration rate; NRI, net reclassification index; QTc, corrected QT.