Urban versus rural trauma recidivism: is there a difference?

PURPOSE

Understanding the characteristics of trauma recidivists may allow trauma centers to tailor prevention programs. We hypothesized that there would be an increased incidence of violent injuries and falls in the urban vs. rural recidivists, respectively.

METHODS

Trauma admissions from 2000 to 2011 were queried for incidences of recidivism. Age (<65 or ≥65 years), gender, Injury Severity Score (ISS, <9 or ≥9), mortality, and injury cause (fall, violence, or other) were analyzed with univariate analyses to test for differences between urban and rural patients. Significant variables were then included in a binary logistic model and further stratified based on environment.

RESULTS

There were a total of 19,600 trauma admissions from 2000 to 2011, representing 18,711 unique patients, with 1,690 admissions (8.6 %) attributed to 801 recidivists (4.3 %). The overall percentages of recidivist trauma admissions attributed to urban and rural patients were 8.6 and 6.9 %, respectively (p < 0.001). When adjusting for age ≥65 years as well as falls and violent injuries, patients from urban environments were at 1.12 times higher odds of being a recidivist than their rural counterparts [odds ratio (OR) 1.12; 95 % confidence interval (CI) 1.01-1.25; p = 0.039]. When stratified into rural and urban groups, falls and violent injuries were significant in both groups of recidivist admissions; however, age ≥65 years was only significant in rural recidivist admissions.

CONCLUSION

An urban trauma admission had 12 % higher odds of being attributed to a recidivist than its rural counterpart, when controlling for age and mechanism of injury (MOI). Age ≥65 years was a significant variable in rural but not urban recidivist admissions. Characterizing the recidivist may allow for targeted prevention and intervention programs to decrease repeat hospital visits.

Regulation of C3 and C3b Activity by Lymphocytes: A New Control Mechanism

Sera from patients with acute lymphoblastic leukemia or active transplant rejection contain high concentrations of a material which regulates C3 and C3b activity. Preliminary isolation of this material reveals that it is able to interfere with both C3 and C3b activity. Lysis of EAC4̄2 by purified C3–C9 or C3 consumption by is inhibited if this material is present when C3 is added. There is no effect if this material is removed before the addition of C3 implying an interaction with native C3 or a C3-like structure which competes with the active enzymatic sites. If, however, this material is added to or cells and then removed, addition of C3bINA or C3bINA and β1H has no effect on the subsequent lysis by C5–C9 () or factors B, D, and C3–C9 (EAC43b). These latter results imply a direct irreversible effect of this substance on bound C3b.