Subsyndromal and syndromal depressive symptoms among older adults with schizophrenia spectrum disorder: Prevalence and associated factors in a multicenter study

Abstract

Background: Few studies have examined the prevalence and correlates of subsyndromal and syndromal depressive symptoms (SSSD) among older adults with schizophrenia spectrum disorder. In this report, we examined the prevalence of SSSD and their associations with sociodemographic characteristics, clinical characteristics of schizophrenia, comorbidity, psychotropic medications, quality of life, functioning and mental health care utilization in a large, multicenter sample of older adults with schizophrenia spectrum disorder.

Methods: Data from the Cohort of individuals with Schizophrenia Aged 55 years or more (CSA) were used to examine the prevalence of SSSD, defined using the Center of Epidemiologic Studies Depression (CESD) scale. Clinical characteristics associated with SSSD were explored.

Results: Among 343 older adults with schizophrenia spectrum disorder, 78.1% had either subsyndromal (30.6%) or syndromal (47.5%) depressive symptoms. SSSD were independently associated with positive and negative symptoms, lower quality of life, non-late-onset psychosis, benzodiazepine use and urbanicity. There were no significant associations of SSSD with other sociodemographic characteristics and psychotropic medications, or with general medical conditions. We found no significant differences in the proportion of participants who were treated with antidepressants between those with syndromal depressive symptoms and those without depression (22.1% vs. 20.0%, p = 0.89). SSSD were not associated with higher mental health care utilization.

Limitations: Data were cross-sectional and depression was not evaluated with a semi-structured interview.

Conclusion: SSSD may be highly prevalent and under-assessed and/or undertreated among older adults with schizophrenia spectrum disorder. Our findings should alert clinicians about the need to assess systematically and regularly depression in this vulnerable population.

Keywords: Antidepressants; Antipsychotic; Depression; Depressive symptoms; Elderly; Older; Prevalence; Risk factors; Schizophrenia; Treatment.