Ida Karlsson

Ida Karlsson

Assistant Professor | Docent
Visiting address: Nobels Väg 12a, 17165 Solna
Postal address: C8 Medicinsk epidemiologi och biostatistik, C8 MEB II Hägg Karlsson, 171 77 Stockholm
Part of:

About me

  • I am Assistant professor and Docent in epidemiology, and lead the research group Epidemiology of cardiometabolic and cognitive aging. My main interest is combining genetic and longitudinal designs to understand complex aging-related traits. My research centers on two themes: 1) understanding how obesity influences late-life health, viewing obesity as a complex and heterogeneous condition with different causes and consequences, and 2) how long-term genetic, biological, and lifestyle factors shape risk and resilience to dementia.

Research

  • Adiposity and the risk of age-related disease
    The project aims to leverage the heterogeneity of adiposity-related traits to understand when, how, and for whom obesity matters for late-life health. My hypothesis is that specific adiposity-related traits have different effects on the risk of age-related diseases, and that these differences are explained by e.g. metabolic factors or accelerated aging. I study adiposity in general (e.g. BMI and body fat distribution), and specific adiposity-related traits: a) metabolically unhealthy vs healthy adiposity, b) environmentally vs genetically driven adiposity, and c) adiposity measured in midlife vs late-life. These adiposity-related traits are associated with substantially increased, vs only slightly increased or even decreased risk of age-related disease (compared to having a normal weight), and by studying what differs between them, I aim to advance our understanding of both the heterogeneity of obesity and of how adiposity in general affects late-life health.


    Life-course risk factors and blood‑based biomarkers for dementia

    This project focuses on understanding how genetic, biological, and modifiable life‑course factors jointly shape risk and resilience to dementia and cognitive decline. The work builds on large, harmonized twin resources, including the Swedish Adoption/Twin Study of Aging (SATSA) and other studies in the Interplay of Genes and Environment across Multiple Studies (IGEMS) consortium. A major focus is the use of blood‑based biomarkers to study the long preclinical phase of dementia in population‑based and genetically informative cohorts. Recent advances in plasma markers of Alzheimer’s disease pathology enable investigation of preclinical disease processes, decades before clinical symptoms, overcoming key limitations of symptom‑based research. By combining repeated biomarker measurements with twin designs, multi‑omics data, and long-term cognitive follow‑up, my research aims to disentangle causal risk factors from genetic and familial confounding, identify early biological pathways leading to dementia, and develop interpretable models for individualized risk prediction and stratification of preclinical disease.

Teaching

  • Course director:

    • An introduction to genetic and molecular epidemiology, Karolinska Institutet, from 2021 (PhD course, 1.5 credits)
    • Statistical Methods, School of Health and Welfare, Jönköping University, 2020 (PhD course, 7.5 credits)

    Lecturer:
    Karolinska Institutet, from 2021:

    • Lectures on genetic epidemiology, cognition, and dementia (bachelor and master level)
    • Leader of seminars, group work, laboratory assignments in epidemiology and biostatistics

    School of Health and Welfare, Jönköping University, 2018-2020:

    • Lectures on statistical methods (doctoral level)
    • Lectures on cognition and dementia (bachelor and master level)

    Supervision/mentoring:

    Former students:

Articles

All other publications

Grants

  • Blood-based biomarkers and molecular changes in preclinical dementia
    The SciLifeLab and Wallenberg National Program for Data-Driven Life Science (DDLS), Academic PhD project 2025
    1 October 2026 - 30 September 2026
  • Improving Dementia Screening with Longitudinal Biomarkers and Twin Designs: Evidence from the SATSA Cohort
    Alzheimerfonden
    1 January 2026 - 31 December 2026
  • The heterogeneity of obesity subtypes: From body mass index towards precision medicine
    Karolinska Institutet Research Grants
    1 November 2024 - 31 October 2026
  • National Institute on Aging
    1 August 2024 - 30 April 2030
  • National Institute on Aging
    15 May 2024 - 28 February 2029
  • Overweight as a heterogenous phenotype - Leveraging differences to understand effects on age-related diseases
    The Strategic Research Program in Epidemiology at Karolinska Institutet
    1 November 2023 - 31 December 2023
  • Swedish Research Council for Health Working Life and Welfare
    1 January 2023 - 31 December 2026
    Research problem and specific questions The purpose of this project is to leverage the heterogeneity of overweight to understand how overweight increases the risk of cardiovascular disease, type 2 diabetes, and dementia. We will study adiposity in general and specific adiposity-related traits:Metabolically unhealthy vs healthy adiposityEnvironmentally vs genetically driven adiposityAdiposity measured in midlife vs late-lifeThus, we can study differences in how the adiposity-related traits associate with the age-related diseases, and if these differences are explained by mediating factors or by an acceleration of aging. We will study:Overweight in general, to highlight genes and biological pathways shared between adiposity and the age-related diseases, and seek to identify factors driving the associations.How metabolic biomarkers (e.g. cholesterol levels, inflammatory markers) and other potential mediators (e.g. depressive symptoms) differ among the adiposity-related traits, and if these factors influence the associations with the age-related diseases.If cellular or multisystem aging (telomere length, epigenetic clocks, and frailty) differ among the adiposity-related traits, and influence the association with the age-related diseases.Data and methodAim 1 uses genetic designs and public data. Aim 2-3 applies advanced epidemiological designs to large longitudinal data from the Health and Retirement Study (USA
    n=37,494) and twin cohorts in the IGEMS consortium (Australia, Denmark, Sweden, and USA
    n=89-136).Plan for project realizationThe data are already available, and the realization and costs concern analyses to answer the research questions. The project is led by an interdisciplinary team of researchers in Sweden, China, and the USA. We will recruit a PhD student, who will conduct four studies within the project, and budget for partial financing of a present PhD student, whose work falls within the proposed project.RelevancePreliminary analyses indicate important differences among the adiposity-related traits, and by examining these differences the project will advance our understanding of the heterogeneity of overweight, and of what drives the negative health effects of adiposity in general. It thereby has the potential to identify preventive strategies reducing the risk of several of our most common causes of morbidity and mortality, and promote a healthier aging.
  • Overweight as a heterogeneous phenotype: Leveraging differences among adiposity-related traits to understand effects on age-related disease
    Foundation for Geriatric Diseases at Karolinska Institutet
    1 October 2022 - 30 September 2025
  • Overweight as a heterogeneous phenotype - Leveraging differences to understand effects on age-related diseases
    Karolinska Institutet’s Research Foundation
    1 October 2022 - 30 September 2024
  • Overweight as a heterogeneous phenotype: Leveraging differences among adiposity-related traits to understand effects on age-related disease
    Loo and Hans Osterman Foundation for Medical Research
    1 July 2022 - 30 June 2025
  • Overweight as a heterogeneous phenotype: Leveraging differences in adiposity-related traits to understand effects on age-related disease
    The Strategic Research Program in Epidemiology at Karolinska Institutet
    1 November 2021 - 31 December 2023
  • Council for International Exchange of Scholars
    1 August 2019 - 29 February 2020
  • Swedish Research Council for Health Working Life and Welfare
    1 January 2019 - 31 December 2021

Employments

  • Assistant Professor, Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, 2022-2028
  • Postdoctoral Researcher, Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, 2021-2022
  • Postdoctoral Researcher, School of Health and Welfare, Institute of Gerontology, Jönköping University, 2017-2020
  • Phd Student, Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, 2012-2017
  • R&D Trainee, Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, 2011-2012

Degrees and Education

  • Docent, Karolinska Institutet, 2024
  • Degree Of Doctor Of Philosophy, Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, 2017
  • Master Of Medical Science, Karolinska Institutet, 2010

Leadership and responsibility assignments

Committee work

  • Member, Junior Faculty Steering Group, Karolinska Institutet, 2024-
  • Member, MEB Work Environment Group, Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, 2021-

Visiting research fellowships

Editorial work

News from KI

Events from KI