PURPOSE: The purpose of this study was to evaluate the effects of age at onset of the first major depressive episode on the clinical features of individuals with major depressive disorder (MDD) in a large cohort of Korean depressed patients. MATERIALS AND METHODS: We recruited 419 MDD patients of age over 18 years from the Clinical Research Center for Depression study in South Korea. At the start of the study, the onset age of the first major depressive episode was self-reported by the subjects. The subjects were divided into four age-at-onset subgroups: childhood and adolescent onset (ages <18), early adult onset (ages 18-44), middle adult onset (ages 45-59), and late onset (ages 60+). Using analysis of covariance (ANCOVA) and ordinal logistic regression analysis with adjusting the effect of age, the relationships between clinical features and age at onset of MDD were evaluated. RESULTS: There was an apparent, but inconsistent correlation between clinical features and age at onset. Earlier onset MDD was significantly associated with higher proportion of female gender [adjusted odds ratio (AOR)=0.570, p=0.022], more previous suicide attempts (AOR=0.635, p=0.038), greater number of previous depressive episodes (F=3.475, p=0.016) and higher scores on the brief psychiatric rating scale (F=3.254, p=0.022), its negative symptom subscale (F=6.082, p<0.0001), and the alcohol use disorder identification test (F=7.061, p<0.0001). CONCLUSION: Early age at onset may increase the likelihood of distinguishable MDD subtype, and age at onset of the first major depressive episode is a promising clinical indicator for the clinical presentation, course, and outcome of MDD.
Adolescent ; Adult ; Age Distribution ; Age of Onset ; Aged ; Depression/epidemiology ; Depressive Disorder, Major/*classification/*diagnosis/psychology ; Female ; Humans ; Life Change Events ; Male ; Middle Aged ; Odds Ratio ; Psychiatric Status Rating Scales ; Regression Analysis ; Republic of Korea ; Suicide, Attempted/psychology ; Young Adult

OBJECTIVE: Among the various psychiatric disorders, depression is a common comorbid condition in cancer patients. Due to the distinct and diverse nature of cancer, the prevalence of depression may be assumed to be affected by differences in primary cancer sites. In this study, we explored the prevalence rates of depression among the ten most prevalent cancers in South Korea using a national patient sample. METHODS: This was a 1-year cross-sectional study using a national patient sample provided by the South Korean National Health Insurance in 2011. We selected all patients who had received ICD-10 codes of the 10 most prevalent cancers and major depressive disorder. Afterwards, the cancer and depression groups were merged and analyzed. RESULTS: The MDD prevalence rate was highest in lung cancer (11.0%), followed by non-Hodgkin's lymphoma (9.2%), prostate (9.1%), bladder (8.8%), breast (7.8%), cervix (7.8%), colorectal (7.7%), stomach (6.9%), liver (6.5%), and thyroid cancer (5.6%). Within all cancer groups, patients with a MDD diagnosis were significantly older (p<0.05) than non-MDD patients. Colorectal, stomach, and thyroid cancer displayed a higher female proportion in the MDD group than the non-MDD group. In the subgroup analysis, the prevalence rate differed by age and sex. CONCLUSION: The prevalence of depression varied according to cancer types. Patients with lung cancer were the most prone to experience depression. Because clinical and psychological factors may influence MDD prevalence, these factors will need to be studied more closely in the future.
Breast ; Cervix Uteri ; Cross-Sectional Studies ; Depression* ; Depressive Disorder, Major ; Diagnosis ; Epidemiology ; Female ; Humans ; International Classification of Diseases ; Korea* ; Liver ; Lung Neoplasms ; Lymphoma, Non-Hodgkin ; National Health Programs ; Prevalence* ; Prostate ; Psychology ; Stomach ; Thyroid Neoplasms ; Urinary Bladder