Frailty, defined by diminished physiological reserve and poor tolerance of acute stressors, markedly raises the likelihood of severe lower respiratory tract infection, intensive care admission, and death from influenza. The same physiology that confers vulnerability also appears to amplify the relative benefit of high-dose and adjuvanted influenza vaccines, making frail older adults among the highest-yield candidates for enhanced formulations rather than the least responsive.
Key Points
- Frailty predicts severe influenza, prolonged hospitalisation, and mortality
- High-dose and adjuvanted vaccines yield greater benefit in frail adults
- Diminished reserve raises risk without eliminating vaccine responsiveness
Longevity Analysis
Frailty is a measurable status of reserve capacity, not an inevitable consequence of chronological age, and it can be quantified well before an acute respiratory infection exposes it. Immune defence in later life depends on the reserve maintained by muscle, circulation, and metabolic capacity, which is why interventions that preserve strength and functional status alter infection outcomes as much as any pharmacological agent. Vaccine selection matched to frailty status, combined with sustained resistance training and nutritional adequacy, forms a coherent strategy against one of the most common precipitants of irreversible functional decline in older adults.
Original published by The Lancet Healthy Longevity, by Chris P Verschoor, George A Kuchel.