Sara Garcia-Ptacek

I am a Senior Lecturer, docent in neuroscience and research group leader at Karolinska Institutet, and a specialist in neurology at Karolinska University Hospital. I combine clinical work with people living with cognitive disorders with research on personalized prevention and treatment of dementia.

I lead the Personalized Diet and Medications for Cognition research group within the Division of Clinical Geriatrics, Department of Neurobiology, Care Sciences and Society. We investigate whether existing medicines and dietary approaches can help preserve cognition, prevent dementia or slow its progression, and why their effects may differ between individuals. A particular focus is APOE genotype and its interaction with medication use, diet and lipid metabolism.

Our work connects population-based epidemiology, clinical registries and studies of blood and cerebrospinal fluid. My clinical experience informs the questions we ask, including how to improve prescribing for people with dementia and how to identify interventions worth testing in clinical trials.

My research aims to identify accessible approaches to preventing and treating dementia, and to establish which individuals might benefit from them. The programme brings together medication repurposing, personalized nutrition and biomarker research, with a particular interest in Alzheimer’s disease and Lewy body dementia.

Medication repurposing and personalized prescribing

We investigate whether medicines already used for other conditions could help prevent dementia or slow cognitive decline. Current research includes lipid-lowering drugs and medicines targeting the renin–angiotensin system, alongside broader investigation of commonly prescribed medications.

A complementary goal is to improve prescribing for people already living with dementia. We study associations between medication use, cognition, survival and other clinically relevant outcomes, considering both potential benefits and harms. We examine whether these relationships differ by APOE genotype, dementia subtype, sex, comorbidities and disease stage.

APOE, diet and cognitive ageing

We investigate how genetic variation, particularly APOE genotype, modifies the relationship between diet and cognitive health. Our work examines foods, dietary patterns and the balance between macronutrients, asking whether dietary approaches may have different implications for different genetic groups.

We use longitudinal population studies and international collaborations to assess the reproducibility of gene–diet interactions. These findings inform hypotheses for intervention studies and the selection of cognitive and biological outcomes. The longer-term aim is to establish whether dietary strategies can be tailored to support dementia prevention and treatment.

Biomarkers and biological mechanisms

We combine epidemiological research with studies of blood and cerebrospinal fluid to investigate biological differences that may help explain variation in outcomes. This includes measuring medications and their metabolites in paired samples, and examining markers of lipid metabolism, blood–brain barrier function and neurodegeneration.

These studies help us investigate how systemic medication exposure relates to cerebrospinal fluid concentrations and whether biological characteristics can inform patient stratification and the selection of interventions for further testing.

Study designs and translation

Our research draws on the Swedish registry for cognitive/dementia disorders (SveDem), population cohorts and international datasets. We use causal inference methods, including target trial emulation, to address specific treatment questions in observational data. Complementary statistical and machine learning approaches help identify patterns and generate hypotheses.

We assess findings through replication across populations and triangulation across study designs and analytical approaches. This work helps distinguish promising candidates from associations that do not withstand more rigorous evaluation, with the aim of guiding the development of clinical trials.

I teach dementia, neurology, epidemiology and research methods at undergraduate, postgraduate and specialist-training levels. My teaching includes medical and physiotherapy students, doctors in clinical training and participants in specialist courses on dementia and old-age psychiatry.

I connect research evidence with clinical decision-making through lectures, seminars, case discussions, team-based learning and bedside teaching. My aim is to help learners assess evidence critically and apply it to the needs of individual patients.

I supervise students undertaking research projects and theses, doctoral students as main and co-supervisor, and postdoctoral researchers. My supervision emphasizes clinically meaningful questions, rigorous study design, transparent analysis and the development of scientific independence.