International Journal of Drug Delivery Technology
Volume 15, Issue 3

Assessment of Cognitive Function in Type 2 Diabetes Mellitus: A Cohort Study Comparing Patients with and without a History of COVID-19 Infection

Anand Vijaya Kumar Palur Ramakrishnan1*, Vijay Kumar Putta1, Rihana Begum Patnool2 

1Department of Pharmacology (DST -FIST Sponsored Department) JSS College of Pharmacy, JSS Academy of Higher Education & Research, Ooty, Nilgiris, Tamil Nadu, India

2 Department of Pharmacy Practice, Chettinad School of Pharmaceutical Sciences, Chettinad Hospital and Research

Institute, Chettinad Academy of Research and Education, Kelambakkam - 603103, Tamil Nadu, India. 

Received: 25th Jun, 2025; Revised: 14th Aug, 2025; Accepted: 5th Sep, 2025; Available Online: 25th Sep, 2025 

ABSTRACT

This cohort study investigates the association between COVID-19 infection and cognitive function in patients with Type 2 Diabetes Mellitus (T2DM), a population inherently at risk for neurocognitive impairment. A total of 1,769 T2DM patients were evaluated, comprising 1,356 individuals with a confirmed history of COVID-19 and 413 without. Standardized cognitive assessments using the Mini-Mental State Examination (MMSE), along with psychosocial (PHQ-9, GAD-7), functional (ADL), and inflammatory parameters (CRP, D-Dimer), were used to quantify outcomes. Patients with a history of COVID-19 exhibited significantly lower global MMSE scores and higher rates of mild and moderate-to-severe cognitive impairment compared to their non-infected counterparts. Additionally, they demonstrated elevated depressive and anxiety symptoms, poorer sleep quality, and increased inflammatory burden. Multivariate regression analysis identified COVID-19 severity, systemic inflammation, and depression scores as significant independent predictors of cognitive decline. These findings highlight a clear relationship between COVID-19 infection and accelerated cognitive deterioration in T2DM patients and underscore the need for integrated post-COVID cognitive screening and multidisciplinary management strategies tailored for this high-risk population.

Keywords: COVID-19, T2DM, Cohort Study, MMSE.

How to cite this article: Anand Vijaya Kumar Palur Ramakrishnan, Vijay Kumar Putta, Rihana Begum Patnool. Assessment of Cognitive Function in Type 2 Diabetes Mellitus: A Cohort Study Comparing Patients with and without a History of COVID-19 Infection. International Journal of Drug Delivery Technology. 2025;15(3):1154-61. doi: 10.25258/ijddt.15.3.34

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