The growing prevalence of severe cognitive impairment in populations, the involvement of a significant number of people of working age in the medical, economic, psychological and social problems associated with late dementia, the insufficiency and inconsistency of information about the mechanisms of formation of these disorders actualize a comprehensive medical and social study of dementia.

The goal is to study the psychosocial mechanisms of the formation of clinical, functional disorders in dementia, to develop comprehensive medical and psychosocial programs to help patients with dementia and those involved in caring for them, based on the proposals of the psychosocial model of dementia.

A selective observational comparative dynamic study of 315 people with Alzheimer’s dementia and 214 people who care for the patients was carried out. The study used clinical, clinical, psychopathological, neuropsychological, psychometric, sociometric, and statistical research methods.

An increase in the severity of dementia contributes to a significant (p <0.05) increase in the number of patients in a dependent position in the family. The appearance of psychotic (painful ideas [r = 0.589]), behavioral (agitation/aggression [r = 0.654]), affective (anxiety [r = 0.536], unstable mood/irritability [r = 0.581]) symptoms of dementia contribute to family role changes structure and increase interpersonal distance in the dyad “caretaker - patient.” Decreased functional activity of the patient (r = 0.758), development of behavioral disorders (aberrant behavior [r = 0.675], agitation/aggression [r = 0.713], impaired night behavior [r = 0.597]), affective symptoms (anxiety [r = 0.685]) contribute to aggravation of the distress of the caregiver. Those who provide unprofessional care for dementia patients in a statistically significant (p <0.05) majority of cases have a high level of emotional involvement in the care process. Changes in family-role and social parameters, a high level of “expressed” emotions of caregivers have an adverse effect on the development of psychotic (r = 0.618), affective (r = 0.701), behavioral (r = 0.837) dementia disorders. The degree of adherence to anti- dementia therapy by the caregiver is one of the important factors determining the amount of care received by the patient (r = 0.698). Agitation/aggression (r = 0.761), anxiety (r = 0.562), sleep disturbances (r = 0.521) contribute to increased compliance. The low satisfaction of the caregiver with premorbid (r = 0.698) and current (r = 0.653) relationships with the patient leads to a decrease in the compliance of the caregiver.

It was revealed that the formation of cognitive impairment is caused by biological factors, their severity depends on the severity of dementia. The mechanism of psychopathological symptoms, functional disorders is heterogeneous, depending on the biological causes and psychosocial conditions of functioning of patients.