Current guidelines still support the use of an SSRI as first choice for the treatment of depression in older adults. Clinicians should keep in mind the old adage “Start low, go slow, but go” with regard to the prescribing of antidepressants in older patients. With older adults, it is a good idea to start at half or quarter of the normal adult starting dose but to increase the dose to well within the therapeutic range for a given antidepressant. Depression is prevalent in older adults in long-term care with estimated prevalence from 11-45%. Depression is associated with poor overall health outcomes and poor quality of life. Interventions are often effective if these patients are identified but treatment can be challenging and require multiple adjustments in medications or treatment strategies.

Chronic alcohol use disorder is an important cause of major neurocognitive disorder. There are several suggested mechanisms for how alcohol use disorder leads to major neurocognitive disorder. Medical treatment of alcohol use disorder can help limit the late effects of alcohol use. Alcohol-induced major neurocognitive disorder can be partially reversible with abstinence but this depends on the severity of the pathology.

Traumatic brain injury (TBI) is more common in older adults than any other age group. It is the most common fall-related injury in adults over the age of 65. The pathogenesis of TBI involves multiple mechanisms. Medications generally do not alter the course of the disease process but can treat the neuropsychiatric symptoms. Mood and anxiety disorders are commonly comorbid with TBI.

Frontotemporal dementia (FTD) is the name of a group of dementias that primarily involve the frontal and temporal lobes of the brain. They are progressive neurodegenerative disorders that are typically diagnosed in individuals under the age of 65. Symptoms of FTD are variable and depend on the subtype of disease but most show some changes in behavior, personality, language, and movement. A history of insidious onset of apathy and lack of concern for self should raise the possibility of FTD. There is no cure for the disease.

Apathy syndrome is a frequently observed condition among older adults, particularly in long-term care environments. Estimates suggest that up to 70% of individuals with Alzheimer’s disease, 40% of those with Parkinson’s disease, and 38% of those with late-life depression may experience symptoms of apathy. Apathy syndrome is a clinical condition characterized by a lack of motivation, interest, or emotional responsiveness. It involves a reduced or diminished ability to initiate and sustain goal-directed behavior, leading to a general indifference or disinterest in one’s surroundings, activities, or social interactions. Some studies have shown improvement in apathy syndrome with methylphenidate.

This chapter provides an introduction to dementia and mild cognitive impairment (MCI). It covers the incidence and prevalence of the most common forms of dementia, and explains the underlying causes in terms of different types of proteinopathy. Risk factors for development of dementia are reviewed, along with protective factors. The role of age is also considered as different subtypes of dementia peak during different age ranges. The contribution of genetics and epigenetics is reviewed, along with the importance of blood supply, sleep, and inflammation. The theory of cognitive and neuronal reserve is introduced as one of the factors which can predict which people are more or less likely to develop dementia and MCI. Connectomics and the arrangement of the brain into circuits is covered, along with developments in neuro-imaging.