A propensity-matched study of the association of cardiothoracic ratio with morbidity and mortality in chronic heart failure.
Pubmed ID: 18237597
Pubmed Central ID: PMC2659172
Journal: The American journal of cardiology
Publication Date: 02/01/2008
Affiliation: Emory University, Atlanta, Georgia, USA.
MeSH Terms: Humans, Male, Female, Aged, Middle Aged, Heart Failure, Hospitalization, Prognosis, Severity of Illness Index, Comorbidity, Kidney Failure, Chronic, Kaplan-Meier Estimate, Morbidity, Cardiomegaly, Confounding Factors, Epidemiologic
Grants: K23 AG019211, R01 HL085561, 1-R01-HL085561-01, K23 AG019211-04, P50-HL077100, R01 HL085561-01, P50 HL077100, UL1 TR000454
Authors: Love TE, Ahmed A, Sui X, Young JB, Giamouzis G, Butler J
Cite As: Giamouzis G, Sui X, Love TE, Butler J, Young JB, Ahmed A. A propensity-matched study of the association of cardiothoracic ratio with morbidity and mortality in chronic heart failure. Am J Cardiol 2008 Feb 1;101(3):343-7.
- Digitalis Investigation Group (DIG)
- Systolic Blood Pressure Intervention Trial (SPRINT)
- Systolic Blood Pressure Intervention Trial Primary Outcome Paper (SPRINT-POP) Data
A high cardiothoracic ratio (CTR) is a marker of an enlarged heart and is associated with poor outcomes in patients with heart failure (HF). To what extent this association is independent of other confounders is not well known. However, to study this, propensity score matching was used to design a study in which HF patients with normal (<or=0.50) and high (>0.50) CTRs were well balanced on all measured baseline covariates. In the Digitalis Investigation Group trial (n=7,788), 4,690 patients had high (>0.50) CTRs. Propensity scores for high CTR were calculated for each patient and were then used to match 2,586 pairs of patients with normal and high CTRs. Matched Cox regression analyses were used to estimate associations of high CTR with mortality and hospitalization during 37 months of median follow-up. All-cause mortality occurred in 28.5% (rate 919 per 10,000 patient-years of follow-up) of patients with normal CTRs and 34.3% (rate 1,185 per 10,000 patient-years) of patients with high CTRs (hazard ratio 1.35, 95% confidence interval [CI] 1.21 to 1.51, p<0.0001). All-cause hospitalization occurred in 64.8% (rate 3,513 per 10,000 patient-years) of patients with normal CTRs and 66.2% (rate 3,932 per 10,000 patient-years) of patients with high CTRs (hazard ratio 1.10, 95% CI 1.01 to 1.20, p=0.032). Respective hazard ratios for other outcomes were 1.48 (95% CI 1.30 to 1.68, p<0.0001) for cardiovascular mortality, 1.57 (95% CI 1.28 to 1.92, p<0.0001) for HF mortality, 1.18 (95% CI 1.08 to 1.30, p=0.001) for cardiovascular hospitalization, and 1.27 (95% CI 1.13 to 1.44, p<0.0001) for HF hospitalization. In conclusion, a baseline CTR>0.50 was associated with increased mortality and morbidity in ambulatory patients with chronic HF.