[A change of patients with methamphetamine-related disorders admitted to Tokyo Metropolitan Matsuzawa Hospital--the comparison between the second and third epidemics of methamphetamine abuse in Japan].

OBJECTIVES

Methamphetamine (MAP) is one of the most commonly abused drugs in Japan. Japan has experienced three major epidemics of MAP abuse. The characteristics of abusers have changed between the second and third epidemics; however, few epidemical studies have investigated these changes. The purpose of this study is to describe the differences in the characteristics of MAP abusers between the second and third epidemics.

METHODS

We surveyed the medical records of patients admitted to Tokyo Metropolitan Matsuzawa Hospital for MAP-related disorders between 1989 and 1993 (n=60; second epidemic group) and between 2004 and 2008 (n=119; third epidemic group). We compared patients' backgrounds and issues related to MAP abuse between the two groups.

RESULTS

Compared to the second epidemic group, more abusers in the third epidemic group were similar to the general population of young people in terms of education level and criminal activity; were on welfare; had dependence syndrome; smoked MAP; and co-abused legal drugs. In contrast, abusers who exhibited antisocial tendencies and injected MAP were more likely to be in the second epidemic group.

CONCLUSIONS

We confirmed changes in the characteristics of MAP abusers between two of the three epidemics of MAP abuse in Japan. These findings suggested that the change of environments from the second epidemics of MAP abuse to the third one influenced the characteristics of MAP-related disorders. So, it is necessary to provide accurate and updated knowledge about MAP for the drug prevention to young people, and the treatment of dependence syndrome will become more important in the future.