Although it has long been appreciated that a healthy balanced diet improves health, there is a growing understanding of the way in which certain nutrients can actually improve immune function. Boosting immune function by the use of “immunonutrition” has been shown to improve outcomes, in particular rates of infective complications, in certain groups of surgical patients.

In this study we examine the immune status of elderly patients who have suffered a hip fracture and are known to be vulnerable to infection and poor post-operative outcomes to identify specific immune defects associated with this particular cohort. This may allow us to explore the potential benefits of immunonutrition in this group of patients in the future.

This was a cohort observational study, in which a series of 16 patients who underwent surgery for hip fractures were followed. The patients were female patients with an age of 60 to 85 years and a mental status questionnaire score of at least 8 out of 10.

Immune function was evaluated prior to surgery, on the day following surgery and then at between days 4 and 7 post-operatively. Samples were tested directly ex-vivo using a variety of flow cytometric assays.

We report profound loss of innate immune function related specifically to monocyte and granulocyte ability to generate a respiratory burst in response to E.coli uptake persisting up to day 7 post-operatively. In addition, serum cytokine levels indicated very poor T cell function, in identifying these patients as particularly vulnerable to infections.