The impact of abdominal aortic aneurysm on muscle mass and energy expenditure: A novel preliminary investigation

Objective: Vascular surgical patients, including those with abdominal aortic aneurysm (AAA), are nutritionally vulnerable. The aim of this study was to compare resting energy expenditure (REE) of patients with AAA relative to age- and gender-matched controls and explore relationships between aneurysm size and muscle mass. Methods: Twenty patients with AAA underwent assessment of REE using indirect calorimetry. Mid-arm circumference and triceps skinfold thickness were measured and corrected arm muscle area calculated. Twenty gender- and age-matched controls were assessed using the same procedures. Results: Mean (SD) age of participants with AAA was 74.7 (7.7) years, size of AAA ranged from 45 to 70 mm. Median (IQR) REE was significantly higher than controls [5990 (5469, 7017) kJ/day versus 5086 (4536, 5886) kJ/day, p =.011; or 69 (64, 80) kJ/kg/day versus 66 (61, 69) kJ/kg/day, p =.046]. While weight-adjusted REE was independent of aneurysm size (r =.200; p =.397), as aneurysm size increased, weight-adjusted corrected arm muscle area decreased (r = −.576; p =.008). Conclusion: The raised REE and decline in muscle mass associated with larger AAA suggest that early detection and attention to nutritional requirements of patients with AAA may be warranted.