Depressive symptoms are associated with reduced neutrophil function in hip fracture patients

Abstract

HighlightDepressive symptoms are a major driver of reduced immunity after hip fracture.

Neutrophil function in young and old caregivers

“…The present results could also be interpreted as a support for the hypothesis that the innate immune system dominates in older age, and that immunosenescence is more evident in adaptive immunity (Franceschi, Bonafe, & Valensin, 2000). It is difficult to draw firm conclusions here, given that, on the whole, alcohol consumption and exercise scores did not significantly predict neutrophil function, also there are currently no agreed cut-offs for determining healthy versus unhealthy neutrophil function; previous studies define this by comparing stressed groups with control healthy participants and examining the correlates of impaired neutrophil function, that is increased infection rates, reduced physical function (Butcher, Killampalli, Chahal, Kaya Alpar, & Lord, 2003;Duggal et al, 2013). This selective effect of chronic caregiving stress has been observed previously, for example the antibody response to some influenza vaccine strains is more susceptible to the effect of psychological stress than others (Gallagher et al, 2009a;Phillips et al, 2005;Vedhara et al, 1999).…”

“…This might seem surprising, considering the initial hypothesis that chronic stress will decrease neutrophil function, but could perhaps be explained by the underlying inflammatory state in these individuals characterized by the higher baseline neutrophil function, and that such inflammation is, in part, driven by the poorer health behaviours adopted by these groupsincreased alcohol intake and reduced physical exercise. It is difficult to draw firm conclusions here, given that, on the whole, alcohol consumption and exercise scores did not significantly predict neutrophil function, also there are currently no agreed cut-offs for determining healthy versus unhealthy neutrophil function; previous studies define this by comparing stressed groups with control healthy participants and examining the correlates of impaired neutrophil function, that is increased infection rates, reduced physical function (Butcher, Killampalli, Chahal, Kaya Alpar, & Lord, 2003;Duggal et al, 2013). Alternatively, it is possible that this aspect of innate immunity, unlike adaptive immune function such as the response to vaccination (Gallagher et al, 2009a,b), is not diminished by the chronic stress of caregiving.…”

“…A negative association between chronic stress and neutrophil superoxide generation has been reported previously in the recently bereaved (Khanfer et al, 2011), who also showed high levels of depression and anxiety. Also, among older hip fracture patients, only those who reported high levels of depression showed poorer neutrophil function, though again this was restricted to superoxide generation (Duggal et al, 2013). Similarly, poor sleep has been associated with alterations in immunity in a number of studies (Besedovsky, Lange, & Born, 2012).…”

“…For neutrophils, many aspects of their bactericidal function, including phagocytosis and ROS generation have been shown to be affected by increasing age (Shaw, Joshi, Greenwood, Panda, & Lord, 2010). Interestingly decreased neutrophil ROS production has been reported in older bereaved adults when compared to their age-matched controls (Khanfer et al, 2011) and in older hip fracture patients who reported depressive symptomatology but not in those who did not display depressive symptoms (Duggal, Upton, Phillips, Hampson, & Lord, 2013). Overall, these data suggest that the way ageing affects neutrophil functioning depends, at least in part, on the presence or absence of, as well as the type of chronic stressor.…”

Anticytomegalovirus antibody titres are not associated with caregiving burden in younger caregivers

“…This argument has been made previously with regard to the emerging impact of a psychosocial/behavioural factor in combination with an existing source of stress which itself had no direct impact on immunity. For example, only older hip fracture patients who developed depression showed suppressed immunity, rather than those who had the stress of hip fracture alone (Duggal, Upton, Phillips, & Lord, ). In younger non‐stressed groups, although still detrimental in the long term, these health behaviours might not demonstrate their impact on particular aspects of immunity until later in life.…”