Tweet
Alzheimers Dement
. 2026 Mar;22(3):e71237.
doi: 10.1002/alz.71237.
Increased incidence of mild cognitive impairment in long COVID patients
Jennifer A Frontera 1 , Arjun V Masurkar 1 , Rebecca A Betensky 2 , Zariya Alvarez 1 , Allal Boutajangout 1 , Joshua Chodosh 1 , Salma Hammam 1 , Jessica Hunter 1 , Li Jiang 1 , Melanie Li 1 , Jon Links 1 , Karyn Marsh 1 , Huize Pang 1 , Floyd Silva 1 , Sujata Thawani 1 , Daria Vasilchenko 1 , Alok Vedvyas 1 , Amin Yakubov 3 , Yulin Ge 1 , Thomas Wisniewski 1
Affiliations
Introduction: Though brain fog is common in Long-coronavirus disease 2019 (Long-COVID), the incidence of mild cognitive impairment (MCI) is unknown.
Methods: In an observational cohort study, recovered COVID-positive, Long-COVID, and COVID-negative subjects underwent blinded evaluation using National Alzheimer's Coordinating Center (NACC) and National Institute on Aging (NIA) -Alzheimer's Association diagnostic criteria for dementia and MCI. The cumulative incidence of MCI was calculated for each group, and the hazard of MCI was compared between groups.
Results: Among 260 subjects, the cumulative incidence of MCI over 4.4 years was higher with Long-COVID (27%) versus recovered-COVID (5%) or COVID-negative status (1%). There was a higher hazard of MCI for patients with Long-COVID compared to those without (hazard ratio [HR] 3.93, 95% confidence interval [CI] 1.86-8.31, p < 0.001), and specifically for the Alzheimer's disease (AD) -related MCI subtype (HR 3.20, 95% confidence interval [CI] 1.14-9.00, p = 0.027).
Discussion: The cumulative incidence and adjusted hazard of MCI (and specifically AD-related MCI) at 4.4 years was significantly higher among Long-COVID patients compared to recovered-COVID and COVID-negative controls.
Keywords: Alzheimer's disease; COVID‐19; MCI; SARS‐CoV‐2; cognition; cumulative incidence; dementia; incidence; long‐COVID; long‐hauler; mild cognitive impairment; post‐COVID syndrome; post‐acute sequelae of COVID.
. 2026 Mar;22(3):e71237.
doi: 10.1002/alz.71237.
Increased incidence of mild cognitive impairment in long COVID patients
Jennifer A Frontera 1 , Arjun V Masurkar 1 , Rebecca A Betensky 2 , Zariya Alvarez 1 , Allal Boutajangout 1 , Joshua Chodosh 1 , Salma Hammam 1 , Jessica Hunter 1 , Li Jiang 1 , Melanie Li 1 , Jon Links 1 , Karyn Marsh 1 , Huize Pang 1 , Floyd Silva 1 , Sujata Thawani 1 , Daria Vasilchenko 1 , Alok Vedvyas 1 , Amin Yakubov 3 , Yulin Ge 1 , Thomas Wisniewski 1
Affiliations
- PMID: 41772376
- DOI: 10.1002/alz.71237
Introduction: Though brain fog is common in Long-coronavirus disease 2019 (Long-COVID), the incidence of mild cognitive impairment (MCI) is unknown.
Methods: In an observational cohort study, recovered COVID-positive, Long-COVID, and COVID-negative subjects underwent blinded evaluation using National Alzheimer's Coordinating Center (NACC) and National Institute on Aging (NIA) -Alzheimer's Association diagnostic criteria for dementia and MCI. The cumulative incidence of MCI was calculated for each group, and the hazard of MCI was compared between groups.
Results: Among 260 subjects, the cumulative incidence of MCI over 4.4 years was higher with Long-COVID (27%) versus recovered-COVID (5%) or COVID-negative status (1%). There was a higher hazard of MCI for patients with Long-COVID compared to those without (hazard ratio [HR] 3.93, 95% confidence interval [CI] 1.86-8.31, p < 0.001), and specifically for the Alzheimer's disease (AD) -related MCI subtype (HR 3.20, 95% confidence interval [CI] 1.14-9.00, p = 0.027).
Discussion: The cumulative incidence and adjusted hazard of MCI (and specifically AD-related MCI) at 4.4 years was significantly higher among Long-COVID patients compared to recovered-COVID and COVID-negative controls.
Keywords: Alzheimer's disease; COVID‐19; MCI; SARS‐CoV‐2; cognition; cumulative incidence; dementia; incidence; long‐COVID; long‐hauler; mild cognitive impairment; post‐COVID syndrome; post‐acute sequelae of COVID.