Relationship between the Arg72Pro Polymorphism of p53 and outcome for patients with traumatic brain injury

Objective: To determine the relationship between the Arg72Pro polymorphism of p53 and the outcome after traumatic brain injury (TBI) in humans. Design and setting: A prospective study was carried out in a ten-bed surgical intensive care unit (SICU) of a university hospital. Patients: The study included 90 caucasian patients who had experienced a severe TBI within the previous 24 h. The exclusion criterion was a previous deficit in the central nervous system. Measurements and results: The main recorded outcomes were values on the Glasgow Outcome Scale (GOS) at discharge from the SICU (GOS-0) and 6 months later (GOS-6). A blood sample was taken from each patient and all samples were analyzed by an allele-specific polymerase chain reaction for detection of Arg72Pro polymorphism of p53. These polymorphisms were tested for their association with values of GOS-0 and GOS-6. A two-tailed value of p < 0.05 was considered statistically significant. The frequency of the argine/argine (Arg/Arg) genotype was greater among the patients who had a bad outcome at GOS-0 (69 vs 31% in the bad-outcome group; p=0.029). A multiple logistic regression analysis showed that patients with the Arg/Arg variation had a 2.9-fold greater risk of having a bad outcome at discharge from the SICU (95% confidence interval, 1.05-8.31; p=0.039 ). There was no similar relationship with respect to GOS-6. Conclusion: The Arg/Arg genotype of the Arg72Pro polymorphism in p53 is associated with increased likelihood of a bad outcome at discharge from the SICU.