BACKGROUND: Substantial uncertainty exists about prevalence of mood disorders in patients with cancer, including those in oncological, haematological, and palliative-care settings. We aimed to quantitatively summarise the prevalence of depression, anxiety, and adjustments disorders in these settings.
METHODS: We searched Medline, PsycINFO, Embase, and Web of Knowledge for studies that examined well-defined depression, anxiety, and adjustment disorder in adults with cancer in oncological, haematological, and palliative-care settings. We restricted studies to those using psychiatric interviews. Studies were reviewed in accordance with PRISMA guidelines and a proportion meta-analysis was done.
FINDINGS: We identified 24 studies with 4007 individuals across seven countries in palliative-care settings. Meta-analytical pooled prevalence of depression defined by the Diagnostic and Statistical Manual of Mental Disorders (DSM) or International Classification of Diseases (ICD) criteria was 16·5% (95% CI 13·1-20·3), 14·3% (11·1-17·9) for DSM-defined major depression, and 9·6% (3·6-18·1) for DSM-defined minor depression. Prevalence of adjustment disorder alone was 15·4% (10·1-21·6) and of anxiety disorders 9·8% (6·8-13·2). Prevalence of all types of depression combined was of 24·6% (17·5-32·4), depression or adjustment disorder 24·7% (20·8-28·8), and all types of mood disorder 29·0% (10·1-52·9). We identified 70 studies with 10,071 individuals across 14 countries in oncological and haematological settings. Prevalence of depression by DSM or ICD criteria was 16·3% (13·4-19·5); for DSM-defined major depression it was 14·9% (12·2-17·7) and for DSM-defined minor depression 19·2% (9·1-31·9). Prevalence of adjustment disorder was 19·4% (14·5-24·8), anxiety 10·3% (5·1-17·0), and dysthymia 2·7% (1·7-4·0). Combination diagnoses were common; all types of depression occurred in 20·7% (12·9-29·8) of patients, depression or adjustment disorder in 31·6% (25·0-38·7), and any mood disorder in 38·2% (28·4-48·6). There were few consistent correlates of depression: there was no effect of age, sex, or clinical setting and inadequate data to examine cancer type and illness duration.
INTERPRETATION: Interview-defined depression and anxiety is less common in patients with cancer than previously thought, although some combination of mood disorders occurs in 30-40% of patients in hospital settings without a significant difference between palliative-care and non-palliative-care settings. Clinicians should remain vigilant for mood complications, not just depression.