Author: Sara Sammallahti

Obesity and overweight are increasing at an alarming rate, and more and more women are entering pregnancy with obesity. Not only related to physical health, maternal early pregnancy overweight and obesity are also associated with consistently higher levels of depressive symptoms throughout and after pregnancy, as shown by psychologist Satu Kumpulainen, who is about to defend her PhD this month.

Looking beyond the immediate risks that manifest during pregnancy and childbirth, Satu also found that those young adults whose mothers had been obese or overweight during pregnancy had altered levels of cortisol – the so-called “stress hormone” – even as adults. This interesting finding supports the hypothesis that maternal overweight and obesity can alter the development of the offspring’s hypothalamic-pituitary-adrenocortical (HPA) axis, an important part of the autonomous nervous system that manages our responses to stress. This could have long-lasting consequences for the child.

Somewhat surprisingly, Satu also found evidence that  challenges the view that lower childhood cognitive functioning poses a risk for adiposity and a less physically active lifestyle in adulthood. Her work revealed that among young Finns, those who had better cognitive abilities as children tended to have lower levels of physical activity during the day and sit more as young adults – downside of being buried behind study books and office desks, perhaps?

Satu Kumpulainen is defending her doctoral dissertation entitled “Obesity and associated health risks – outcomes of maternal early pregnancy obesity and child’s cognition” in the Faculty of Medicine, University of Helsinki, on 25 January 2019 at 12:00. The event is open for anyone who wishes to hear more about the topic! The examination will take place at the following address: Päärakennus, Auditorium XV, Unioninkatu 34.  Professor Annick Bogaerts, from KU Leuven in Belgium, will serve as the opponent, and Professor Katri Räikkönen-Talvitie as the custos. The dissertation is also available in electronic form through the E-thesis service.

/Sara Sammallahti

We were very happy to welcome a long-term collaborator, Professor Rebecca Reynolds from the University of Edinburgh for a visit recently. Rebecca is an expert in the mechanisms that link prenatal development and pregnancy risk factors such as maternal obesity with offspring development across the life span. A specialist in endocrinology by background, Rebecca does both patient work and research including clinical trials, studies in the lab, and epidemiological research.

Our group first got to know Rebecca in person when she very kindly agreed to act as the official opponent for one of the PhD students in the group. Since then, we have been fortunate to work with Rebecca and her group on several projects. Most recently, this collaboration has produced articles such as those showing that

• Maternal overweight and obesity early on in pregnancy are associated with symptoms of depression during and after pregnancy (Kumpulainen et al., Psychological Medicine 2018)
• Maternal depressive symptoms during pregnancy and toddler psychiatric problems may be associated with alterations in the structure of the placenta (Lahti-Pulkkinen et al., Scientific Reports 2018)
• Maternal depressive symptoms throughout pregnancy are associated with increased symptoms of ADHD in the child (Wolford et al, Plos One 2017)

This was not the first time Rebecca visited us – and in return, members of the DePsy group have visited Edinburgh on several occasions, both for conferences and meetings and for longer research visits.

During this visit, Rebecca gave an interesting talk on the prenatal programming of the stress axis, held a journal club meeting, and worked on the several manuscripts that are being prepared together at the moment. And of course, visits like this aren’t only about the science itself: we also had the opportunity to take some time off to catch up and try some Finnish cheese and Scottish short-bread – which work together very well!

Our group leader, professor Katri Räikkönen was elected as chairman of the Helsinki University Collegium. Congratulations, Katri!

Children who are born preterm – before 37 weeks of gestation – are more likely than term-born peers to have problems in cognitive functioning and may experience more mental health problems. Then again, most preterm infants grow up to be just as happy, healthy and smart as any of their peers. Among those preterm infants, who is at risk?

Sara Sammallahti showed in her thesis that early growth during the first months of life after preterm birth predicts adult cognitive functioning. Those preterm participants who grew well during early infancy performed better in neuropsychological tests in adulthood, received higher grades in school and were less likely to have been given special education. After taking into account many potential confounders, it seemed that this association was not explained merely by prenatal factors.

Higher intakes of energy, human milk, and macronutrients were also associated with better performance in adulthood. However, the associations between these nutritional intakes and long-term cognitive outcomes seemed largely driven by early morbidity: early illnesses can interfere with nutrition, and those infants who were severely ill as neonates were also more likely to experience neurodevelopmental problems later on.

Interestingly, mental health outcomes were not associated with early growth. This could suggest that the mechanisms that underlie the increased risk of mental health problems among preterm individuals are different from the mechanisms that explain why preterm individuals have, on average, more cognitive problems than term-born peers do.

Taken together, the results encourage further research into how we could best support the optimal growth and development of preterm neonates – what we do during those precious early weeks and months may  have life-long consequences.

Sara Sammallahti, M.Psych., B.Med., will defend her doctoral dissertation entitled “Growth after preterm birth and cognitive functioning and mental health in adulthood” (“Keskosten kasvu ja aikuisiän kognitiiviset taidot ja mielenterveys”) at the Faculty of Medicine, University of Helsinki, on 7th April 2018 at 10:00. The public examination will take place at the Seth Wichmann Hall, Naistenklinikka, Haartmaninkatu 2. Professor Ken Ong from the University of Cambridge will serve as the opponent. Academy professor Katri Räikkönen, adjunct professor Eero Kajantie, and Professor Sture Andersson have supervised the thesis. The dissertation will also be available in electronic form through the E-thesis service 10 days before the defense. Contact details: sara.sammallahti@helsinki.fi .

If you have not yet heard the distinctive southern drawl of the newest member of the DEPSY research group, you soon likely will. Rachel Robinson, originally from Texas, USA, recently joined the DEPSY research group as a doctoral student and will be focusing on the RECAP Preterm project.

Rachel moved to Finland in 2013 to pursue an international Master’s degree in Public Health. When asked why she chose Finland, Rachel highlights the fact that she wanted to pursue her MPH in a program with an international focus and in a country with a different health care system than in the USA. During and after completing her MPH studies at the University of Eastern Finland, she worked at the Työterveyslaitos (Finnish Institute for Occupational Health) Cochrane Work Review group, writing Cochrane systematic reviews on occupational health interventions. Since 2015, she worked for the European Chemicals Agency, predominately tasked with developing the scientific and regulatory knowledge management wiki and helping administer the chemical substance evaluation process in collaboration with the EU member states.

Prior to moving to Finland, Rachel completed a Bachelor’s of Science in Health, with an emphasis in community health from Texas Tech University. Her desire to return to health research with an emphasis on early developmental factors stems largely from her time in Malawi with a Community Based Orphan and Widow Care agency for people impacted by HIV/AIDs, which included mobile medical clinic coordination, crisis nursery infant care, and international volunteer coordination. These experiences have fueled her passion for public health research and identifying interventions, which can improve people’s health and overall quality of life.

Rachel has a Finnish partner, two young stepdaughters (aged 6 & 9), and a dachshund. She enjoys reading a captivating book while sipping a strong cup of coffee, vintage furniture upholstery, Finnish summer cottage life and sauna, board games, and a good conversation over a delicious meal.

I’ve heard people say doing epidemiological studies must be easy, compared to lab work – you just sit on your computer and run analyses! Well, there’s a fair share of looking at the screen involved, too, but before that, you actually have to get the data. And looking at the numbers on the screen, you sort of forget all the endless hours of work by so many people that went into getting those numbers there.

Lately, we celebrated something of a milestone for the data collection phase of the ITU project: our last placenta was born. Since 2012, on every day of the year, one of the nurses, doctors, psychologists or research assistants involved in ITU has been on call. Whenever one of the moms who participate in ITU gave birth, the person on call would get to one of the maternity hospitals in the metropolitan area to take samples of the placenta. After five years and more than 500 placentas, we were quite a happy bunch, celebrating the end of this phase together.

Now, of course, begins another exciting phase: boiling all that work down to numbers, and then, to new information about well-being during pregnancy, and the long-term effects of prenatal factors on the developing child. First, lab time, and then – computer time!

/Sara Sammallahti

In a cohort of Finnish 25-year-olds, those who had higher cognitive ability in early childhood were more inactive physically in young adulthood, as shown in a study by Kumpulainen et al., published in Health Psychology.

Physical inactivity means both low levels of moderate-to-vigorous physical activity (such as brisk walking and running), and high levels of sedentary behaviours (such as reading, TV viewing and computer use, while sitting or laying down). Both of these factors independently predict adverse health-related outcomes. One proposed factor underlying individual differences in health related behaviours, including physical activity, is early life cognitive ability. In our study, we examined whether cognitive ability in childhood predicts physical activity and inactivity in young adulthood.

The study sample comprised 500 participants of the Arvo Ylppö Longitudinal Study (AYLS). In childhood, at an average of 4.5 years, the participants underwent neurocognitive testing. In adulthood, at the mean age of 25 years, they wore a wrist-worn accelerometer for a week, to provide data on physical activity. They also self-reported their level of physical activity during occupational and leisure-time.

Results showed that in young adulthood, higher cognitive ability in childhood was associated with more sedentary time and less time spent in light physical activity such as slow walking. It was also associated with lower intensity of daily physical activity, and decreased odds of having a physically demanding job in young adulthood.

It may seem surprising that those children with high cognitive ability were physically less active in adulthood: in many cases, high cognitive ability is associated with positive health-related behaviours. In our study, however, the associations seemed (partly) explained by differences in the educational level that the participants had attained or were pursuing. This would suggest that lower physical activity and more time spent in sedentary behaviours may reflect the lower strenuousness of daily activities in those with a higher educational level.

Physical activity patterns are moderately stable across adulthood and physical inactivity tends to increase with age. Increasing awareness of the benefits of physical activity-related health promotion should be targeted at young adults whose daily activities include a lot of sedentary behaviours.

In one of our previous posts, we wrote about the Helsinki Birth Cohort – one of the cohorts Developmental Psychology group is working with – which includes information about men and women who were separated temporarily from their biological parents in childhood due to evacuation to Sweden or Denmark from the strains of World War II. In that post, we shared findings from the study by Jari Lahti and colleagues, who found that variants of the FKBP5 gene interacted with this objectively recorded early life stress in predicting moderate to severe levels of depressive symptoms in midlife.

Recently, Anna Suarez and colleagues extended these findings further in a paper published in Psychosomatic Medicine journal by exploring whether FKBP5 single-nucleotide polymorphisms (SNPs) interacted with early separation from parents on physical health, namely on type 2 diabetes, cardiovascular disease, and quantitative glycemic traits.

FKBP5 gene plays an important role in regulating our stress reaction system – the hypothalamic-pituitary-adrenal axis (HPA axis). Dozens of studies have found that variants, or SNPs, of this gene interact with stress experienced early in life (e.g. neglect, abuse, or separation from parents) in predicting mental health problems in adulthood. This means that people who share the same stressful childhood experience but have different versions of FKBP5 gene, have different probability of developing psychiatric problems that are related to dysregulation of the HPA axis.

The study by Suarez and colleagues shows a similar effect for physical health: those who were separated from parents during war and had at least one “vulnerable” copy of the FKBP5 SNPs (rs1360780, rs9394309, rs9470080) had higher levels of blood glucose when measured with oral glucose tolerance test. While there was no significant interaction of FKBP5 and early life stress on type 2 diabetes and cardiovascular disease, high levels of glucose predict increased risk of developing these conditions in the future. As Depsy continues to follow-up the participants from Helsinki Birth Cohort, future studies will tell if the increased risk in the genetically vulnerable individuals exposed to early life stress will translate into manifest disease as the participants of the cohort age.

Awareness of vulnerability to certain conditions based on genetic makeup and childhood experience pose a great potential for timely prediction and prevention.

/ Anna Suarez

We are continuously involved in large international collaborative projects. This year, as before, our group has contributed to several genome-wide association studies (GWAS), projects that demand a huge number of participants to identify variation in the genome that is associated with a specific trait.

One of these studies was just published in Nature Communications (Zillikens et al. (2017). Large meta-analysis of genome-wide association studies identifies five loci for lean body mass). It was found that lean body mass (which consists mainly of muscle mass), was associated with a number of single-nucleotide polymorphisms. These associations were discovered in a sample of 38,292 people from 20 cohorts, and subjects from 33 additional studies were used to replicate the findings (with a total sample of 63,475 people).

Another GWAS meta-analysis was recently published in Molecular Psychiatry (Trampush et al (2017). GWAS meta-analysis reveals novel loci and genetic correlates for general cognitive function: a report from the COGENT consortium). In this study, general cognitive functioning was found to be associated with new loci, based on data from 24 cohorts (enrolling 35,298 individuals). However, the effects of any individual single-nucleotide polymorphisms were very small: in other words, small differences in the genome each accounted only for a very small portion of the variance in cognitive performance – as tends to be the case with psychological traits.

/Sara Sammallahti

Preterm birth may have long-term consequences on emotional wellbeing and behaviour lasting into adulthood. This was found by Pyhälä, Wolford and others and published earlier this year in Pediatrics. In more detail, adults born preterm at very low birth weight reported more internalizing and socially avoidant personality problems, as well as less externalizing problems than those born full term. The results indicate that former severely preterm infants are on average more withdrawn and experience more emotional problems which often manifest as depressive or anxiety symptoms. Also, they express less socially unacceptable behavior such as rule-breaking or intrusive behavior.

The study was carried out as an individual participant data meta-analysis within our international research network called Adults Born Preterm International Collaboration (APIC). APIC is a group of researchers around the world who aim to combine their forces to answer questions related to preterm birth that cannot be answered in any one single cohort study alone.

Now, for the first time, it enabled us to combine adulthood follow-up data on self-reported mental health problems from six preterm cohort studies from five different countries including USA, Canada, Germany, Norway and Finland. The final study sample included altogether 747 adults born preterm and 1512 born at term.

Collaboration and data pooling across several studies offers us an opportunity to overcome some of the limitations that previous studies have had. For example, we have already learned from earlier studies based on nationwide registries that the risk for diagnosed psychiatric disorders is higher among adults born preterm in comparison to those born at full term. Further, a few original cohort studies have indicated that adults born preterm may also themselves report more mental health problems. But registries only include severe disorders diagnosed by medical doctors, and individual cohort studies, in turn, are relatively small which makes it difficult to detect all group differences, for example, whether the effects of preterm birth are different in men and women.

Therefore, this new study specifically adds to our knowledge of those subjective symptoms that may not exceed the clinical threshold or may not have been diagnosed, but may still impair psychological wellbeing, social life and normal everyday functioning. It was also possible to show that these effects of preterm birth were fairly similar among women and men, and among those who were born small in relation to the duration of pregnancy.

Given the emotional and social problems that adults born preterm may experience, supporting their coping skills and peer relationship skills already in childhood may be warranted in addition to the early support for parents. But simultaneously, it is important to note that not all adults born preterm experience mental health problems and most of them do well. Besides being a vulnerability factor, preterm birth may in fact serve as a protective factor in some respect as was demonstrated in their lesser amount of externalizing problems in our study. Therefore, finding the key features to plan timely and targeted preventive interventions to promote long-term resilience in all areas of psychological wellbeing among preterm individuals is an important goal for future research.

/ Elina Wolford & Riikka Pyhälä