• morbidity and mortality [ Time Frame: 1 year ]
  

• - antioxidant/oxidant parameters and inflammatory mediators - postoperative insulin resistance - mitochondrial dysfunction in the skeletal muscle - postoperative delirium incidence, duration and severity [ Time Frame: 1 week ]
  

Rationale: A growing medical concern is the increase in the number of very old patients, especially the patients undergoing hip fracture surgery are rapidly increasing in numbers. Hip surgery in these old patients induces serious morbidity and gives rise to excessive mortality rates. Studies with perioperative nutritional interventions performed within this population have shown improved clinical outcome, but were not well controlled and lack insight in the working mechanism. Therefore nutritional intervention studies are needed using a single nutrient. In trauma patients for instance it is known that the administration of glutamine (as a single amino acid) reduces morbidity, which is probably related to its antioxidant properties; reducing oxidative stress and insulin resistance. As an antioxidant the amino acid taurine has even greater potential providing benefit in several groups of patients. Elderly hip fracture patients have very low plasma levels of antioxidants which make them highly vulnerable for oxidative stress and related insulin resistance.In elderly patients with a hip fracture, it is hypothesized that taurine lowers oxidative stress and the related harmful insulin resistance, thereby reducing morbidity and mortality.

Objective: Our primary objective is to reduce morbidity and consequent mortality in the elderly hip fracture patient by the administration of taurine.

Study design: A double blind placebo controlled intervention study at the surgery department of the Medical Center Alkmaar. The study consists of three parts: 1. A dose finding study; 2. Main study: outcome study on morbidity and mortality; 3. A study on insulin resistance, parallel to the main study.

Study population: Patients of both genders and any ethnicity, who will undergo primary surgery for a hip fracture, aged over 75 years, will be eligible for the study.

Intervention: Patients will receive from the moment of admission oral administration of taurine (3g/day or 6g/day, depending on results of the dose finding study) or placebo.

Main study parameters/endpoints: The main study parameter is the morbidity and consequent mortality. The secondary study parameters are oxidative stress, postoperative insulin resistance, mitochondrial dysfunction in skeletal muscle and postoperative delirium.

Nature and extent of the burden and risks associated with participation, benefit and group relatedness: The possible benefit of the study is related to the effect of taurine. Oral administration of taurine, as an antioxidant, perioperatively, can reduce morbidity and consequent mortality, reduce oxidative stress, counteract the postoperative insulin resistance and thereby enhance the clinical outcome of the elderly hip fracture patient. Research showed that taurine can be safely administered to humans and no adverse effects are reported. A part of the patients will undergo a hyperinsulinaemic euglycaemic clamp to assess hepatic and peripheral insulin sensitivity.