Table 1 Examples of indicators of deteriorating health reserves

• The physical reserve: indicators that can be used in practice to capture physical deterioration, i.e. a disabling condition affecting the mobility of the body, can include chronic pain, grip strength or physical mobility tests

• The socioemotional reserve: proxy variables [16] of socioemotional deterioration are including Clinical Interview Schedule - Revised (CIS-r) [17], Malaise inventory [18] or other validated screening instrument assessing psychological distress

• The cognitive reserve: the Trail Making Scale or other cognitive assessment can reveal deterioration in cognitive reserve

• The physiological reserve: to measure physiological deterioration or a deregulation of allostasis, allostatic load (AL) [19] or other biological scores [20] have been developed to measure the consequence of a prolonged activation of the stress response system by external challenges, leading to physiological imbalances across systems