Background:
Obesity can adversely affect most organ systems and increases the risk of comorbidities likely to be of consequence for patients with complex adult congenital heart disease (ACHD). Conversely, several studies have demonstrated that low body mass index (BMI) is a risk factor for heart failure and adverse outcomes after cardiac surgery. However, there are currently no data regarding the impact of BMI in ACHD.
Methods:
We examined the charts of 87 randomly selected, complex ACHD patients whose first visit to our institution was at 18-22 years old. Patients were categorized according to BMI at initial visit: underweight (BMI < 18.5 kg/m
2
), normal (BMI 18.5 - 24.9 kg/m
2
), overweight/obese (BMI ≥ 25 kg/m
2
). Events occurring during follow-up were recorded. Data was censured on 1/1/2014. Cardiac events were defined as a composite of cardiac death, heart transplantation or admission for heart failure.
Results:
The cohort included patients with the following diagnoses: tetralogy of Fallot n=31, Mustard n=28, Fontan n=17, ccTGA n=9 and aortic coarctation n=2. The median (IQR) duration of follow-up was 8.7 (4.2 - 1.8) years. See table for distribution and outcomes by BMI category. Cardiac events occurred in 17/87 patients. After adjustment for age, sex, and underlying disease, the underweight group had increased risk of cardiac events (HR=12.9, 95% CI: 2.8-61.5, p < 0.05). Kaplan-Meier curves demonstrate the poorer prognosis of underweight patients (Figure).
Conclusions:
Underweight was associated with increased risk of late cardiac events in ACHD patients. We were unable to demonstrate significant overweight/obesity impact.
History of heart failure hospitalisation predicts mortality in adult congenital heart disease morbidity and mortality in ACHD
