Sensory declines in vision, hearing, and smell diminish independence and lead to social isolation, a major driver of depression and morbidity.

Impaired immunity increases hospitalization and death from infections and decreases vaccine efficacy in the elderly.

Persistent inflammation impairs immunity while worsening chronic diseases— increasing frailty, morbidity, and the risk of premature death.

Cognitive impairment diminishes mobility, independence, and quality of life, and erodes health by interfering with management of chronic diseases.

Loss of muscle function decreases mobility and independence. Frailty compounds the risk of falls, a major cause of accidental death in the elderly.