The clinical features and outcome of crush patients with acute kidney injury after the Wenchuan earthquake: differences between elderly and younger adults.

BACKGROUND

On May 12, 2008, a devastating earthquake hit Wenchuan county of China's Sichuan province. Acute kidney injury (AKI) is one of the most lethal but reversible complications of crush syndrome after an earthquake. However, little is known about the epidemiological features of elderly crush patients with AKI. The aim of the present study is to compare clinical features and outcome of crush related AKI between elderly and younger adults in the Wenchuan earthquake.

MATERIALS AND METHODS

A questionnaire was sent to 17 reference hospitals that treated the victims after the earthquake. Clinical and laboratory characteristics of crush patients with AKI were retrospectively analysed.

RESULTS

228 victims experienced crush related AKI, of which 211 were adults, including 45 elderly (age ≥ 65 years) and 166 younger adults (age, 15-64 years). Compared with the resident population, the percentage of patients was higher amongst elderly (19.7% versus 7.6%, P<0.001). The distribution of gender was similar in elderly and younger adults. Mean systolic blood pressure was higher in elderly groups. Although no statistical differences in number of injury and injury severity score were observed between elderly and younger adults, elderly victims had lower frequency of extremities crush injury; higher incidences of thoracic traumas, limb, rib, and vertebral fractures; lower serum creatinine, potassium and creatinine kinase levels; lower incidence of oliguria or anuria; lower dialysis requirement; underwent less fasciotomies and amputations, received less blood and plasma transfusions. Mortality were 17.8% and 10.2% in elderly and younger adults, respectively (P=0.165). Stratified analysis demonstrated the elderly receiving dialysis had higher mortality rate compared with younger patients (62.5% versus 10.5%, P<0.001). Multivariate logistic regression analysis indicated that need for dialysis and sepsis were independent risk factors for death in the elderly patients.

CONCLUSIONS

Elderly crush victims more frequently developed AKI in the Wenchuan earthquake, and they differ from younger adults in injury patterns and treatment modalities. The elderly patients with AKI requiring dialysis were at a relatively high risk of mortality.