Trends, correlates, and disease patterns of antipsychotic use among elderly persons in Taiwan.

Abstract

We used the population-based database to investigate the trends, correlates, and disease patterns of antipsychotic use among elderly people in Taiwan. The National Health Research Institutes provided a database of 1,000,000 random subjects for health service studies. We analyzed a sample of subjects over the age of 65 years from 1997 to 2005. The trends in and factors associated with antipsychotic use were detected. We also examined the proportions of antipsychotics used for psychiatric and medical disorders. The 1-year prevalence of antipsychotic use in elderly persons increased from 9.8% in 1997 to 12.8% in 2005. The prevalence of first-generation antipsychotic (FGA) use increased from 9.8% to 11.6%, and the prevalence of second-generation antipsychotic (SGA) use increased greatly from 0.01% to 2.02%. Higher prevalence of both FGAs and SGAs were associated with age and higher Charlson Comorbidity Index scores. Psychiatric disorders were commonly found in SGA users (80.8%), whereas only 19.3% of the FGA users had psychiatric disorders. Among the major psychiatric disorders, greater proportions of antipsychotic use were for senile and presenile organic psychotic conditions, other organic psychotic conditions, and affective psychoses. FGAs were much more commonly prescribed for nonpsychiatric disorders, including diseases of symptoms, signs, and ill-defined conditions, the digestive system, and the respiratory system. The prevalence of antipsychotic use, particularly the use of SGAs, increased greatly from 1997 to 2005 among elderly persons in Taiwan. SGAs were most used by subjects with psychiatric disorders, and FGAs were most used by those with nonpsychiatric disorders.