Glucose metabolism disorders and cognitive performance in ageing. A prospective study of middle-aged and elderly individuals
Thesis event information
Date and time of the thesis defence
Place of the thesis defence
Markku Larmas auditorium (H1091)
Topic of the dissertation
Glucose metabolism disorders and cognitive performance in ageing. A prospective study of middle-aged and elderly individuals
Doctoral candidate
M.D. Sanna Rotonen
Faculty and unit
University of Oulu Graduate School, Faculty of Medicine, Research Unit of Population Health
Subject of study
Medicine
Opponent
Associate Professor Merja Laine, University of Helsinki
Custos
Professor Sirkka Keinänen-Kiukaanniemi, University of Oulu
Prediabetes and insulin resistance predict memory problems before the onset of diabetes
The doctoral research of M.D. Sanna Rotonen demonstrates that cognitive decline may begin already in the early stages of impaired glucose metabolism—before the development of type 2 diabetes. The findings highlight the importance of midlife lifestyle factors for brain health and suggest that reducing insulin resistance and disturbances in glucose metabolism may influence the risk of memory problems later in life.
The study examined the associations between impaired glucose metabolism and cognitive performance from two perspectives: through existing research evidence and through long term follow up in the Oulu 45 cohort, which consists of individuals born in 1945 and followed from age 57 to age 69.
A systematic literature review confirmed that type 2 diabetes accelerates age related cognitive decline. In addition, some studies showed that even prediabetes was associated with an increased risk of mild cognitive impairment and its progression toward dementia (Substudy 1).
The findings from the Oulu 45 cohort supported these observations. Long standing prediabetes or its development during follow up was a clear risk factor for declining cognitive performance (Substudy 2). Worsening insulin resistance during follow up also increased the risk of mild cognitive impairment. Furthermore, participants with low levels of physical activity had a higher risk of memory decline, underscoring the importance of everyday physical activity in maintaining brain health (Substudy 3).
The study also found that decline in cognitive functioning is reflected in health related quality of life. Thus, early disturbances in glucose metabolism are not only markers of future diabetes risk but are also linked to brain health and functional capacity (Substudy 3).
The doctoral research of MD Sanna Rotonen emphasizes the need for early identification and management of impaired glucose metabolism. Early lifestyle changes may help prevent or slow the development of memory problems and support good cognitive functioning as people age.
The study examined the associations between impaired glucose metabolism and cognitive performance from two perspectives: through existing research evidence and through long term follow up in the Oulu 45 cohort, which consists of individuals born in 1945 and followed from age 57 to age 69.
A systematic literature review confirmed that type 2 diabetes accelerates age related cognitive decline. In addition, some studies showed that even prediabetes was associated with an increased risk of mild cognitive impairment and its progression toward dementia (Substudy 1).
The findings from the Oulu 45 cohort supported these observations. Long standing prediabetes or its development during follow up was a clear risk factor for declining cognitive performance (Substudy 2). Worsening insulin resistance during follow up also increased the risk of mild cognitive impairment. Furthermore, participants with low levels of physical activity had a higher risk of memory decline, underscoring the importance of everyday physical activity in maintaining brain health (Substudy 3).
The study also found that decline in cognitive functioning is reflected in health related quality of life. Thus, early disturbances in glucose metabolism are not only markers of future diabetes risk but are also linked to brain health and functional capacity (Substudy 3).
The doctoral research of MD Sanna Rotonen emphasizes the need for early identification and management of impaired glucose metabolism. Early lifestyle changes may help prevent or slow the development of memory problems and support good cognitive functioning as people age.
Created 11.2.2026 | Updated 13.2.2026