Immunonutrition in Acute Geriatric Care: Clinical Outcomes, Inflammatory Profiles, and Immune Responses

Abstract

Background and aims: Malnutrition is common in acutely ill geriatric patients, worsening immune function and clinical outcomes. Immunonutrition, containing nutrients like omega-3 fatty acids, arginin and glutamine, may improve recovery in this population. This study aimed to evaluate the impact of immunonutrition on clinical outcomes, inflammatory markers, and immune responses in frail, hospitalized older adults.

Methods: This is a retrospective observational study. In total, 36 subjects, during hospitalization, received either an immunonutrition formula or isoproteic and isocaloric enteral nutrition. The primary outcome was the length of hospital stay (LOS), with secondary outcomes focused on inflammatory cytokines and immune parameters within a week of hospitalization.

Results: Patients were primarily oldest-old, with a mean age of 88.6 years ± 4.9 (range 79-96). The immunonutrition group had a significantly shorter LOS (11.37 ± 4.87 vs. 16.82 ± 10.83 days, p = 0.05) and showed increases in key cytokines (G-CSF, INF-α2, IL-12p70, IL-15, IL-2, and IL-3, p < 0.05) enhanced immune function. A decrease in T cells and an increased B/T cell ratio was also observed. No significant differences in infection rates or 90-day survival were found.

Conclusions: Enteral immunonutrition improved clinical outcomes by reducing LOS and modulating immune responses in frail patients, suggesting potential benefits in recovery. Further studies are needed to confirm these findings.

Keywords: aging; frailty; hospital; immunosenescence; nutrition.

Figure 1

Effect of immunonutrition on cytokine and growth factor levels. This figure shows the changes in cytokine and growth factor levels between the Control (CTL) group and the Immunonutrition (IN) group in a cohort of geriatric patients. The cytokines and factors measured include G-CSF, INF-A2, IL-12 p70, IL-15, IL-2, and IL-3. The data are presented as violin plots, where each plot compares the CTL group (blue) with the IN group (red). Statistically significant differences between the two groups are marked with their respective p-values. These results suggest that immunonutrition may play a role in modulating inflammatory and immune responses in this patient population.

Figure 2

Impact of immunonutrition on T cell bubsets and B/T Ratio. This figure illustrates the changes in T cell (CD3+), B/T cell ratio, and Tc cell (CD3+CD8+) populations between the Control (CTL) group and the Immunonutrition (IN) group in a cohort of geriatric patients. The data are presented as violin plots, with the CTL group shown in blue and the IN group shown in red. Statistically significant differences between groups are annotated with corresponding p-values. These findings suggest that immunonutrition may enhance the immune response by modulating T cell populations and altering the B/T ratio in older patients.

Figure 3

Effect of immunonutrition on telomerase activity. This figure presents the changes in telomerase activity between the Control (CTL) and Immunonutrition (IN) groups. Panel (A) shows the T1/T0 ratio of telomerase activity in both CTL and IN groups. There was no significant difference in the T1/T0 ratio between the two groups (p = 0.8859), indicating comparable telomerase activity over time. Panel (B) depicts individual changes in telomerase activity (absorbance) from baseline (T0) to follow-up (T1) for the CTL and IN groups. In the CTL group, telomerase activity significantly decreased over time (p = 0.0061), while the IN group showed a non-significant reduction (p = 0.1934), suggesting that immunonutrition may help preserve telomerase activity compared to the control condition.