Connecting the Dots With Life Course Epidemiology

By taking a long view of our health throughout our lives, scientists can spot patterns that help them break the chain of chronic illnesses. Eero Kajantie is a leading researcher in this field of study – known as life course epidemiology – and Professor of Lifecourse Medicine at the University of Oulu. He has spent his career digging into questions like how social, genetic and environmental factors can influence our health, how our births can cause ripple effects throughout our lives, and why some people suffer from multiple chronic health conditions.

Much of Eero’s work has focused on people who were born before the 37th week of pregnancy, commonly referred to as preterm. To do so, his research leverages administrative data collected by authorities, along with the Northern Finland Birth Cohorts. This is a group of 20,000 people who have been studied since birth, participating in periodic questionnaires and clinical examinations – a treasure trove for life course researchers. By tracking people’s trajectories over their entire lives (and in some cases, their children’s lives) his research has uncovered trends in people’s long-term health outcomes, from cardiovascular to mental health, as well as societal outcomes such as their level of education and quality of life. One such finding Eero’s work has captured is that people born very premature have far fewer children than those born at term – but whether this is due to them finding it biologically harder to conceive, personal choice, or difficulties finding a partner is not yet clear. “Since starting a family affects one’s life satisfaction, that’s something we really want to understand,” he says.

Overall, Eero’s research has found that “most people born preterm – even those born extremely preterm – are healthy and live normal lives. They don’t need to pay much attention to that fact as they age.” However, it has also shown that, compared to the general population, people born preterm are at a higher risk of diseases such as anxiety disorders, depression, certain types of cardiovascular disease, and type 2 diabetes. “This knowledge is helpful for physicians, who can be more vigilant and proactive when conducting assessments” – potentially stopping these diseases in their tracks.

These types of chronic conditions are also part of the multimorbidity spectrum – where “people have more than one disorder, which doesn’t occur at random.” Multimorbidity forms the focus of a new cross-disciplinary research initiative at Oulu called Health Dimensions, which Eero is leading alongside vice chair Professor Johannes Kettunen, the Scientific Director of Biocenter Oulu. By mapping the prevalence of multimorbidity across the population – in part by leveraging the Northern Finland Birth Cohort – the research initiative aims to uncover the factors that increase people’s susceptibility. It will also explore ethical ways of using AI to identify groups prone to multimorbidity, and promote impactful interventions that could save lives. Turning its immense resources towards this mission is just one example of Oulu’s commitment to promoting human health and wellbeing, alongside other Sustainable Development Goals. 

The initiative is primed for success thanks to the university’s fostering of strong connections between researchers with different areas of expertise, with molecular researchers, clinical health researchers, and population researchers channeling their energies toward a singular theme. “Health Dimensions’s scope is much broader than any single research group can attain, and targets the problem of multimorbidity from different levels.” This integrated approach is crucial given multimorbidity stems from a web of interlinked factors, from a person’s genetics, to their socioeconomic status, to their age and gender.

As well as being a world-leading institution in the field of lifelong health, Oulu has a staunchly global outlook. This is illustrated by its cross-border research, with Eero’s team collaborating with researchers in Malawi and Bangladesh, but is also apparent at its base in Finland. “My colleagues who have moved from outside Finland say it is easy to relocate here. It’s an international university which appreciates talent from wherever the talent comes from. We’re looking for talented people who can take their area of research forward, and help close certain gaps of knowledge that have been identified.” 

At Oulu, the knowledge that’s gleaned isn’t confined to labs or journals – researchers work with the real-world impacts of their studies in mind. “The Faculty of Medicine has strong connections with the university hospital. Many university researchers also hold clinical positions there, so the transition between clinical work and theory is very smooth.

“The culture at the university is very forward-looking, and it’s easy to make connections. People come together to find solutions.”