Objectives: Various studies described the psychological impact of the mandatory preventive social isolation (lockdown) caused by COVID-19 across different age groups. However, no research had specifically analyzed the effects of lockdown on the cognitive performance of older adults with preexisting cognitive decline. This study aimed to determine the impact of lockdown on the cognitive functions of individuals with cognitive decline.

Methods: Argentina was one of the countries with the longest lockdown periods. Older adults in Argentina experienced extended lockdowns lasting several months, significantly limiting their social interactions and routine activities. Cognitive reevaluations were conducted on 16 patients who had attended a memory clinic with cognitive complaints and were evaluated before the lockdown (group 1). Their progression was compared with 16 patients evaluated and reevaluated over a similar period but without undergoing a lockdown (group 2). To compared the progression of both groups a “change index” (CI) were calculated for each test ((score assessment 1 – score assessment 2)/number of months between assessment 1 and assessment 2))

Results: Patient from group 1 and 2 were paired by age (M group 1 = 77.2, DS group 1 = 6.2, M group2 = 77.3 DS group2 = 6.6, p=.98), yearsof education (M group 1 = 13.6, DS group 1 = 2.8, M group2 = 13.9 DS group2 = 3.0, p=.81), Beck depression inventory score (M group 1 = 12.2, DS group 1 = 7.2, M group2 = 13.9 DS group2 = 7.4, p = .54) and Addenbrooke’s Cognitive Examination (ACE. M group 1 = 76.2, DS group 1 = 14.4, M group2 = 76.0 DS group2 = 20.7, p = .97) score at the first assessment. Group 1 showed a significant and greater increased of false positive than group 2 in Rey Auditory Verbal Learning Test recognition (M CIgroup 1 = –.31, DS CIgroup 1 = .38, M CIgroup 2 = –.1, DS CIgroup 2 = .44, p < .05). Results indicated that patients who experienced the lockdown exhibited a greater cognitive decline compared to the control group.

Conclusions: The findings suggest that the lockdown accelerated cognitive deterioration in individuals with memory complaints.