Brain Sciences


Meet the expert: Professor Mika Kivimaki

Mika Kivimaki is Professor and Chair of Social Epidemiology within the Division of Psychiatry. His research focuses on modifiable risk factors and prognostic factors for major adult-onset chronic diseases of public health relevance, including dementia.

Mika Kivimaki

What attracted you to the area of epidemiology and why is it important?

Originally from Finland, I initially studied classical music and started my working life as a violinist in the Finnish Radio Symphony Orchestra, one of the two most highly regarded orchestras in the country.

In my late 20s I moved into academia to study psychology, completing an MA, followed by a PhD, both on stress. In 1997 with Professor Jussi Vahtera I decided significantly to expand a small cohort of 800 public sector workers and recruited >10 000 new public sector workers into what would eventually become the >50,000 strong Finnish Public Sector Study.

As my interest in large, longitudinal cohort studies grew I found my initial interest in psychology and stress shifting gradually towards population health and epidemiology, in particular the aetiology of chronic diseases of major public health importance.

Epidemiology is the study of disease at the population level. In addition to investigating how and why diseases occur, it is used to plan population-level disease prevention policies and to guide the management of patients in whom disease has already developed.

Thus, epidemiology provides answers to crucial population health questions, such as what can be done to avoid disease onset and what does or doesn’t work at each stage of the disease process once it has started.

What is the Whitehall II study? 

Whitehall II is internationally recognised as a unique epidemiological resource for study of the aetiology and prognosis of mental and physical illnesses. It is an on-going cohort study of 10,308 participants aged 35-55 recruited from the British Civil Service in 1985. 

Since the baseline examination, clinical data have been collected from the cohort every two to five years with a high level of participation. The 13th data collection is now in progress and will be completed by the end of 2022. 

For those interested, Whitehall data are available via the Dementias Platform UK portal. The data cover a wide range of risk and protective factors, measures of preclinical and clinical disease and tests of cognitive, physical and mental function. Biosamples from the participants have been enriched by genotyping, metabolomic intermediates and proteomic profiling. The entire cohort has been linked to electronic health records. 

Findings from Whitehall II study publications have been included in the evidence underpinning several clinical guidelines and public health policies.

Can you tell us about your current research? 

In recent years work with my research teams and collaborators has become increasingly interdisciplinary. In addition to aetiology and prognosis we now apply epidemiological and biopsychosocial findings to co-design and test evidence-based interventions. 

One example is our Wellcome Trust funded project which aims to identify new drug targets for preventing or delaying dementia. For this, we analyse stored plasma samples drawn from Whitehall II participants when they were middle aged. Plasma is biologically informative due to the presence of protein signals. These provide imprints of subclinical dementia progression that can be identified via proteomic profiling decades before clinical symptoms. A further advantage of studying proteins for drug discovery is that they are highly modifiable and cover as much as 98% of approved medication targets.

We have also a number of projects on environmental, lifestyle, socioeconomic and psychological factors that drive the development of other major chronic conditions, such as type 2 diabetes and cardiovascular disease, and ageing outcomes, such as multimorbidity, frailty and disability. 

What aspect of your work most excites you and why?

More than any specific aspect of my work, it is the scientific process itself that most excites me. The process, familiar to all scientists, of keeping abreast of the literature, identifying the questions to be answered next, gathering and analysing the data and writing up doesn’t sound that exciting. 

However, I find orchestrating the development of a research question with colleagues and collaborators and steering it as it develops to fruition through publication and into policy and intervention enormously rewarding. 

What would you say to someone who is considering whether to study epidemiology in relation to mental health at UCL?

It is an excellent choice! Epidemiology is a fascinating discipline. It allows you to learn about factors that affect the development and progression of mental disorders and how mental and physical illnesses are related to each other. 

Furthermore, if you are interested in doing research, UCL provides excellent opportunities to integrate epidemiology with experimental, interventional, and clinical approaches. This allows you to gain a really deep understanding of your topic of interest.

What’s the best advice you would give your younger self?

Perhaps I would remind myself of this famous quote “the greatest enemy of knowledge is not ignorance; it is the illusion of knowledge.” It highlights the importance of having an open mind, but also of critical thinking, a point emphasised by the physicist Stephen Hawkins and historian Daniel J. Boorstin. 

I first heard this quote in an inspiring UCL seminar series in which Nobel laureates, Barry Marshall and Martin Evans, described the process that led to their breakthroughs. Marshall discovered the causal role of the bacterium Helicobacter pylori in peptic ulcer, a finding which led to an effective treatment of this disease. Evans, in turn, was the first scientist to identify embryonic stem cells.