The epidemiology of psychiatric disorders among women with breast cancer in South Korea: analysis of national registry data

OBJECTIVE: Population-based data on the epidemiology of psychiatric disorders in patients with breast cancer are lacking. Because the National Health Insurance (NHI) Program in South Korea is a compulsory social insurance system covering the entire Korean population, the NHI is a good source of information for epidemiological studies. In the present study, we examined the incidence of psychiatric disorders among Korean women newly diagnosed with breast cancer using the NHI Corporation (NHIC) database. METHODS: Data were collected for adult women newly diagnosed with breast cancer using the claim database and cancer registration files of the NHIC from 2005 to 2008. We analysed data for women diagnosed with psychiatric disorders over a 5-year period, from 2004 (at least 1 year before the cancer registration date) to 2009 (at least 1 year after the cancer registration date). RESULTS: We identified 6536 patients with psychiatric disorders among 42 190 women with breast cancer. The most prevalent psychiatric disorder was anxiety disorder (N = 2518). The incidence rates of anxiety disorders, depressive disorders, sleep disorders and adjustment disorders were 27.08, 22.41, 10.57 and 4.35 cases per 1000 person-year, respectively. CONCLUSION: The incidence rates of psychiatric disorders in Korean women with breast cancer from the nationwide database were much lower than found by previous reports using screening tools. The finding implicates that psychiatric disorders among breast cancer patients tend to be underdiagnosed and undertreated in actual clinical practice. Our epidemiological findings provide important information for establishing a national strategy of cancer care to detect and manage psychiatric problems.ope