Late-Onset Psychosis; Is It Real?

Korea, like other nations, is experiencing a demographic transition featuring the rapid expansion of the proportion of aged persons. Elderly-related mental health issues are gaining prominence. Late-onset psychosis, which has been a well-recognized but poorly-understood phenomenon, has emerged as an important issue in geriatrics. It is unclear whether this psychosis occurs for the first time at this later stage of life in the absence of organic brain dysfunction is a manifestation of schizophrenia in older age (i.e., variant or subtype of schizophrenia) or represents a disorder that is distinct from typical schizophrenia. For patients who develop psychosis in later life, the arbitrary and inconsistent use of terminology, each with different age cut-offs (i.e., 40, 45, or 60 years), have complicated the understanding of the issue and patient treatment. The current diagnostic confusion originated from historical differences in the nosocological approach that have continued to influence current psychiatric classification systems. Various terms have been used to designate primary late-onset psychosis. These include paranoia, presenile delusional insanity, lateonset schizophrenia, late paraphrenia, delusional disorder, paranoid psychosis, late-onset schizophrenia disorders and verylate-onset schizophrenia-like psychosis.1-7 Despite the varying landscape of terminology, these phenomena present a rather consistent clinical picture. Similarities have been found between late-onset psychosis and early-onset psychosis in terms of the social isolation, associated depressive symptoms and certain neuroimaging findings. But, notable differences between earlyand late-onset psychosis exist. Terminological/diagnostic confusion and uncertainty will continue because the cause and underlying pathophysiological mechanisms of psychosis regardless of age-onset are still unknown. Proposed diagnostic criteria had been not clearly outlined, which has led to ongoing inconsistency and confusion about how the criteria should be applied clinically and in research studies.8-10 Moreover, whether distinguishing schizoLate-Onset Psychosis; Is It Real?