A Retrospective Survey on the Clinical Presentation of Ketamine Abusers in a Hong Kong Emergency Department

Objective: Ketamine is one of the commonest abusing agents in Hong Kong. Our study aims to identify their clinical pattern of presentations to emergency departments. Method: This is a retrospective survey study. The studied group was ketamine abusers being referred to us from a source out of emergency department (ED). Control group was randomly selected from patients attending our ED. The electronic records of the ketamine abusers and the controls in the past 3 years (1st April 2004-31st March 2007) were reviewed and analysed. Result: Total 91 subjects (48 in ketamine group, 43 in control group) were included. The mean age of ketamine abusers and control group are 21 and 22.2 year-old respectively. Most of them (97.9%) did not declare their background of ketamine abuse. The mean 3-year attendance rate for the ketamine group was 2.38 and for control group was 0.91, with a difference of 1.47 (95% CI 0.54-2.41, p=0.003). Most of their illnesses were diagnosed as epigastric pain (25%), followed by upper respiratory tract infection (18.8%), head injury (10.4%) and urinary tract infection (10.4%). Significantly higher number of ketamine abusers presented with epigastric pain compared with control group (odds ratio 143, p<0.001). Conclusion: Most teenage ketamine abusers do not declare their background of drug abuse when they present to emergency departments. They tend to have a higher frequency of attendances. Most of their presenting problems are related to gastrointestinal system.