Female Sex as a Risk Factor for In-Hospital Mortality Among Children Undergoing Cardiac Surgery

Abstract

Background-The purpose of this study was to investigate whether sex disparity in cardiovascular outcomes exists in children who undergo cardiac surgery. Methods and Results-Statewide hospital discharge data from California from 1995 to 1997 were used. Children Ͻ21years old who had a procedure code (by ICD9-CM) that indicated cardiac surgery were selected. The outcome variable was binary, in-hospital death versus alive at discharge. Twenty-three surgical procedures were selected and adjusted for risk by procedure type. We used logistic regression analysis to evaluate the effect of sex on in-hospital mortality, controlling for age, race and ethnicity, type of insurance, home income, type of admission, date and month of surgery, hospital case volume, and type of procedure. There were 6593 cases of cardiac surgery, with 345 in-hospital deaths (mortality rate 5.23%). Crude mortality rates for males (4.98%) and females (5.54%) were not significantly different. However, fewer females were neonates, and females had more low-risk procedures than males. Multivariate logistic regression showed that females had a higher odds ratio (OR) for mortality than males (OR 1.51, PϽ0.01). The OR for mortality was 3.86 for neonates and 2.98 for infants compared with children aged Ն1 year. Low-volume hospitals had higher mortality rates than high-volume hospitals (OR 1.67, PϽ0.01). The risk-adjusted length of hospital stay and charges were similar between females and males. Conclusions-For children undergoing cardiac surgery, female sex was associated with 51% higher odds of death than male sex. The mechanism by which female sex acts as a risk factor requires further investigation.

Effect of Sex and Race on Outcome in Patients Undergoing Congenital Heart Surgery: An Analysis of The Society of Thoracic Surgeons Congenital Heart Surgery Database

“…Although the findings of previous studies have been somewhat inconsistent, several have suggested an association between sex and mortality rate, with girls having a greater mortality risk [6, 7]. In the present study, multivariable analysis with adjustment for patient factors, comorbidities, and STAT mortality category revealed a shorter postoperative LOS in girls but no difference in in-hospital mortality or rate of the occurrence of postoperative complications.…”

Effects of Race, Ethnicity, and Gender on Surgical Mortality in Hypoplastic Left Heart Syndrome

“…Although some studies have shown increased mortality for female infants undergoing cardiac procedures [4, 9, 27, 38], we did not find a gender discrepancy in adjusted analysis for any of the three palliative procedures. Other studies looking specifically at risk factors associated with S1P for HLHS also have not found a gender difference [25, 28, 37, 39].…”

Modelling Survival and Mortality Risk to 15 Years of Age for a National Cohort of Children with Serious Congenital Heart Defects Diagnosed in Infancy

“…Despite recognition of the complexity of survival analysis in children with CHDs, for whom both predictors and mortality are time-dependent [11], examples of survival models including time-varying covariates are rare and few previous studies have explicitly stated the temporal ordering of childhood factors and their inter-relationships, directly or through mediating factors, with mortality. We addressed the methodological challenges of repeat observations, and also adjusted for the effects of clustering by cardiac centre, through the development of discrete-time hierarchical survival models [19], [20] and multilevel multiple imputation [44], [45] of missing values. The use of imputed datasets, by allowing us to include all cohort children and procedures in the analyses, reduced the likelihood of bias that can result from restricting analyses to the small proportion of children with complete data [21].…”

“…Morris [29] demonstrated that girls with COA and TGA had higher mortality prior to intervention, whereas Fyler [43] reported a higher death rate for boys during the first year of life. Other authors have highlighted that girls experience higher perioperative mortality related to paediatric cardiac surgery [44]–[47]. As the ratio of boys to girls affected varies by specific cardiac defect, these sex differences may be confounded by the severity of cardiac diagnosis.…”