Public Health

Cognitive loss following COVID-19 has been recognized as an acute and long-term sequela of the disease, with deficits in attention, executive functioning, and memory (Panagea et al., 2024; Hampshire et al., 2021). Older adults from racial and ethnic minority backgrounds face heightened risks of severe COVID-19 outcomes due to aging-related vulnerabilities and a higher prevalence of comorbidities, yet post-infection cognitive impairment in these populations remains unexplored. Prior studies have been limited by suboptimal assessments, and recruitment of predominantly non-Hispanic White adults. Our pilot study, therefore, aims to address this gap by examining the relationship between persistent COVID-19 symptoms, and cognitive outcomes in a small sample of racially/ethnically diverse older adults.

20 participants were engaged from Mount Sinai's COVID-19 Biobank (mean age 63.4 ± 4.9 years; 14.6 ± 3.9 years of education; 55% male; race/ethnicity: 45% Black, 15% Hispanic, 5% Asian, 35% non-Hispanic White), and hospitalized in 2020. Inclusion criteria were: (1) History of SARS-CoV-2 infection or serum antibody positive (2) age ≥55, and (3) English-speaking. Participants were remotely administered the NACC UDS 3.0 and several questionnaires, including one assessing persistent COVID-19 symptoms. Univariate analyses were used to compare demographic characteristics between groups.

No group differences were found between participants with and without loss of smell/taste during infection. However, those with long-term loss of smell/taste (>4 weeks) scored significantly lower on CERAD total, delay, and recognition (p = 0.016, 0.042). Additionally, longer hospitalization durations were significantly associated with poorer global cognition (p = 0.001), verbal memory (p = 0.014), auditory working memory (p = 0.043), simple attention and processing speed (p < 0.001), as well as verbal fluency (p = 0.009).

Participants with long-term loss of smell/taste and longer hospitalization had persistent cognitive impairment approximately 2.9 years post COVID-19 infection. Therefore, findings suggest the importance of studying the long-term role of infections similar to COVID-19 on Alzheimer's Disease and Related-Dementias (AD/ADRD) risk, particularly in a diverse sample of older populations. Further research with larger, longitudinal samples is needed to clarify the underlying mechanisms and inform cognitive rehabilitation strategies.