Obesity, underweight in youth linked to adverse cardiac surgery outcomes
Children, adolescents and young adults who are obese, underweight or severely underweight face an increased risk of composite adverse cardiac surgery outcome of death, major adverse event and/or wound infection, independent of other risk factors, a study has found.
The multicentre retrospective cohort study included 18,337 patients aged 10 to 35 years scheduled to undergo a congenital heart disease operation between January 2010 and December 2015. Operative mortality and a composite outcome (operative mortality, major adverse event, prolonged hospital length of stay and wound infection/dehiscence) were the primary endpoints.
Multivariate logistic regression analysis was performed to test the associations between age-/sex-adjusted body mass index (BMI) percentiles and the outcomes, with adjustment for patient-level risk factors.
Of the patients, 16 percent were obese, 15 percent overweight, 53 percent normal weight, 7 percent underweight and 9 percent severely underweight. The greatest risks of operative mortality (p=0.04) and composite outcome (p<0.0001) were observed among severely underweight and obese patients. Severely underweight BMI increased the likelihood of unplanned cardiac operation and reoperation for bleeding, whereas obesity increased the risk of wound infection.
On multivariable analysis, the risk of composite outcome was notably elevated in obese (odds ratio [OR], 1.28; p=0.008), severely underweight (OR, 1.29; p<0.0001) and underweight patients (OR, 1.39; p=0.002). However, the association between BMI and operative mortality was no longer significant.
The study underscores that there are significant associations between body composition and perioperative outcome after congenital heart surgery, which may not be otherwise explained by patient and procedure factors, according to researchers.
Further studies are warranted to elucidate the mechanisms underlying the observed associations, researchers said, adding that interventions aimed at improving nutrition in underweight patients and weight loss in obese subjects need to be studied both for their efficacy in affecting BMI and effect on cardiac surgery outcome.