Quality of diet and level of physical performance related to inflammatory markers in community-dwelling frail, elderly people.

OBJECTIVE

The aim of this study was to assess whether diet quality and functional status were associated with serum levels of interleukin (IL)-6 and tumor necrosis factor (TNF)-α in frail, elderly, community-dwelling individuals.

METHODS

Seventy-eight frail, elderly individuals (age ≥65 y, usual gait speed <0.6 m/s and Mini Nutritional Assessment <24) participated in this cross-sectional study from the National Home Healthcare Services in Gangbuk-gu, Seoul, South Korea. Diet quality was assessed using mean adequacy ratio (MAR) of the diet, which was calculated by averaging the sum of the nutrient adequacy ratios (NAR) for the intakes of energy, protein, and 11 micronutrients. Grip strength was measured as an indicator of muscle strength, and short physical performance battery (SPPB) was measured as an indicator of physical performance. The levels of the inflammatory markers IL-6 and TNF-α were obtained from serum samples.

RESULTS

MAR and NAR scores for phosphorus; vitamins A, B, and B; and niacin were negatively associated with IL-6 (β = -0.006, -0.004, -0.004, -0.007, -0.004, and -0.005, respectively; P < 0.05). SPPB score, as well as NAR scores for vitamin B, niacin, and vitamin C, were negatively associated with TNF-α (β = -0.098, -0.006, -0.006, and -0.004, respectively; P < 0.05).

CONCLUSION

MAR of the diet was inversely associated with IL-6 concentration in frail elderly individuals, and higher SPPB score was associated with lower levels of TNF-α. Results from the present study suggest that improving diet quality and physical performance might lower levels of inflammation in this frail, elderly population.