Effect of age on resting energy expenditure in patients with cancer.

Objective: Because older patients with cancer are at high risk for developing malnutrition, it is critical to understand their energy needs and to feed them appropriately. The aim of this study was to determine whether there are differences in resting energy expenditure between younger and older adults with cancer and in various age groups of older patients.

Methods: This retrospective, observational, and descriptive study from a single center included adult (≥18 to <60 y) and older (≥60 y) outpatients with gastrointestinal tract and head and neck cancers. According to the World Health Organization classification for adults and Pan American Health Organization for older individuals, nutritional status was estimated using body mass index. Nutritional risk screening was used to assess the nutritional risk and Patient-Generated Subjective Global Assessment for those at risk. Resting energy expenditure (REE) was measured by indirect calorimetry coupled to a gas exchange canopy. Bodystat and Quadscan 4000 multifrequency electrical bioimpedance devices were used to assess body composition at four frequencies (5, 50, 100, and 200 kHz).

Results: The study included 326 patients of whom 197 were older (60.4%), 244 were men (74.8%), 197 had gastric cancer (60.4%), and 129 had head and neck cancer (39.6%). Most patients had advanced cancer (stages III and IV) and had not undergone cancer treatment in the previous 3 mo. Compared with the younger adults, patients ≥60 y had a higher rate of malnutrition (88.4 versus 54.3%; P < 0.001), a higher percentage of fat-free mass deficit (88.3 versus 74.4%; P < 0.001), and higher percentage of fat mass (91.4 versus 58.9% adult; P < 0.001). The REE of older patients (1263.3 [234.1] kcal/d) was lower than that of patients ≥18 to <60 y (1382.5 [210.5] kcal/d; P < 0.001), for women (1055.2 kcal/d for the older adults versus 1214.3 kcal/d for younger adults), and men (1337.9 versus 1433 kcal/d; P = 0.001). The REE comparison categorized by decades has shown that for patients <60 y, an REE greater than those for individuals 60 to 69 y, 70 to 79 y, and ≥80 y (P < 0.001). REE in patients 60 to 69 y was greater than for those ≥80 y (P < 0.001). When compared with the Harris-Benedict formula, the REE intraclass correlation coefficient for all older patients was 0.514 (95% confidence interval [CI], 0.064-0.736); for ages 60 to 69 y it was 0.527 (95% CI, 0.126-0.733), and for ages >70 y, it was 0.466 (95% CI, -0.080 to -0.756).

Conclusion: Measured REE in patients with cancer decreases with age. This finding is critical for appropriate caloric provision for older patients with cancer.