A propensity-matched study of the effect of diabetes on the natural history of heart failure: variations by sex and age.
BACKGROUND
Poor prognosis in heart failure (HF) patients with diabetes is often attributed to increased co-morbidity and advanced disease. Further, this effect may be worse in women.


OBJECTIVE
To determine whether the effect of diabetes on outcomes and the sex-related variation persisted in a propensity score-matched HF population, and whether the sex-related variation was a function of age.


METHODS
Of the 7788 HF patients in the Digitalis Investigation Group trial, 2218 had a history of diabetes. Propensity score for diabetes was calculated for each patient using a non-parsimonious logistic regression model incorporating all measured baseline covariates, and was used to match 2056 (93%) diabetic patients with 2056 non-diabetic patients.


RESULTS
All-cause mortality occurred in 135 (25%) and 216 (39%) women without and with diabetes (adjusted HR = 1.67; 95% CI = 1.34 to 2.08; p<0.001). Among men, 535 (36%) and 609 (41%) patients without and with diabetes died from all causes (adjusted HR = 1.21; 95% CI = 1.07 to 1.36; p = 0.002). Sex-diabetes interaction (overall adjusted p<0.001) was only significant in patients > or = 65 years (15% absolute risk increase in women; multivariable p for interaction = 0.005), but not in younger patients (2% increase in women; p for interaction = 0.173). Risk-adjusted HR (95% CI) for all-cause hospitalisation for women and men were 1.49 (1.28 to 1.72) and 1.21 (1.11 to 1.32), respectively, also with significant sex-diabetes interaction (p = 0.011).


CONCLUSIONS
Diabetes-associated increases in morbidity and mortality in chronic HF were more pronounced in women, and theses sex-related differences in outcomes were primarily observed in elderly patients.
Ahmed
Ali
A
University of Alabama at Birmingham and VA Medical Center, Birmingham, AL 35294-2041, USA. aahmed@uab.edu
Aban
Inmaculada B
IB
Vaccarino
Viola
V
Lloyd-Jones
Donald M
DM
Goff
David C
DC
Zhao
Jiannan
J
Love
Thomas E
TE
Ritchie
Christine
C
Ovalle
Fernando
F
Gambassi
Giovanni
G
Dell'Italia
Louis J
LJ
D000367:Age Factors; D000407:Alabama / Q000453:epidemiology; D003925:Diabetic Angiopathies / Q000209:etiology* / Q000401:mortality; D005260:Female; D006333:Heart Failure / Q000209:etiology* / Q000401:mortality; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011379:Prognosis; D016032:Randomized Controlled Trials as Topic; D012737:Sex Factors