Reconsidering the overdiagnosis of mild cognitive impairment for dementia prevention among adults aged ≥80 years

A diagnosis at the stage of mild cognitive impairment (MCI) is encouraged to promote dementia prevention since intensive intervention during the mild stage is thought to be effective for dementia prevention. Many adults aged >= 80 years hope to prevent dementia; however, several issues should be considered regarding the diagnosis of MCI. First, the diagnosis of MCI is not clear-cut in actual medical practice, with the differentiation of MCI from normal states and mild dementia being blurred. Second, although MCI due to Alzheimer's disease can be differentiated from MCI without pathological changes, interventions specific to MCI due to Alzheimer's disease have not been developed. Third, the diagnosis of MCI can cause self-stigma, leading to psychological effects such as depression and anxiety for both the patients and their families, which can be risk factors for developing dementia for patients. In addition, medical resources are limited and diagnosing MCI is costly in medical human resources. Considering these issues, diagnosing MCI to promote dementia prevention should be viewed from the perspective of the individual patient's interests, especially for those aged >= 80 years. The final decision regarding receiving a diagnosis or not should be the patient's; therefore, it is necessary to increase patients' health literacy, which requires medical professionals to provide them with appropriate evidence-based information. At the same time, it is important to provide psychological support to people who have been diagnosed.