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

PURPOSE

The population-based National Health Insurance database was used to investigate the trends, correlates, and disease patterns for elderly people in Taiwan who use antidepressants.

METHODS

The National Health Research Institute provided a database of 1000,000 random subjects for study. We created a sample of subjects who were older than 65 years from 1997 to 2005. Trends, prevalence, and associated factors of antidepressant use were detected. We also examined the proportion of antidepressant use for psychiatric and medical disorders.

RESULTS

The one-year prevalence of antidepressant use in elderly persons increased from 5.8 % in 1997 to 9.8 % in 2005. The one-year prevalence rates of tricyclic antidepressant (TCA), selective serotonin reuptake inhibitor (SSRI), serotonin-norepinephrine reuptake inhibitor (SNRI), serotonin modulator, and other antidepressant use in 2005 were 5.3, 2.6, 0.4, 2.9, and 0.6 %, respectively. Overall antidepressant use was higher for those in the 75- to 84-year-old age group, females, and those with higher Charlson Comorbidity Index scores. Among subjects using TCAs, 77.6 % users did not have a psychiatric diagnosis. Psychiatric disorders were commonly found in most SSRI and SNRI users (85.1 and 90.1 %, respectively). Subjects using SSRIs and SNRIs had higher proportions of psychiatric disorders such as neurotic depression, major depression, senile and presenile organic psychotic conditions, and anxiety.

CONCLUSION

The prevalence of antidepressant use among elderly persons increased greatly from 1997 to 2005. SSRIs, SNRIs, and other antidepressants were used mostly by subjects with psychiatric disorders, whereas TCAs were used mostly by subjects with nonpsychiatric disorders.