Cohort profile: Genetic data in the German Socio-Economic Panel Innovation Sample (SOEP-G)

by Philipp D. Koellinger, Aysu Okbay, Hyeokmoon Kweon, Annemarie Schweinert, Richard Karlsson Linnér, Jan Goebel, David Richte, Lisa Reiber, Bettina Maria Zweck, Daniel W. Belsky, Pietro Biroli, Rui Mata, Elliot M. Tucker-Drob, K. Paige Harden, Gert Wagner, Ralph Hertwig

The German Socio-Economic Panel (SOEP) serves a global research community by providing representative annual longitudinal data of respondents living in private households in Germany. The dataset offers a valuable life course panorama, encompassing living conditions, socioeconomic status, familial connections, personality traits, values, preferences, health, and well-being. To amplify research opportunities further, we have extended the SOEP Innovation Sample (SOEP-IS) by collecting genetic data from 2,598 participants, yielding the first genotyped dataset for Germany based on a representative population sample (SOEP-G). The sample includes 107 full-sibling pairs, 501 parent-offspring pairs, and 152 triads, which overlap with the parent-offspring pairs. Leveraging the results from well-powered genome-wide association studies, we created a repository comprising 66 polygenic indices (PGIs) in the SOEP-G sample. We show that the PGIs for height, BMI, and educational attainment capture 22∼24%, 12∼13%, and 9% of the variance in the respective phenotypes. Using the PGIs for height and BMI, we demonstrate that the considerable increase in average height and the decrease in average BMI in more recent birth cohorts cannot be attributed to genetic shifts within the German population or to age effects alone. These findings suggest an important role of improved environmental conditions in driving these changes. Furthermore, we show that higher values in the PGIs for educational attainment and the highest math class are associated with better self-rated health, illustrating complex relationships between genetics, cognition, behavior, socio-economic status, and health. In summary, the SOEP-G data and the PGI repository we created provide a valuable resource for studying individual differences, inequalities, life-course development, health, and interactions between genetic predispositions and the environment.

Metformin in the prevention of type 2 diabetes after gestational diabetes in postnatal women (OMAhA): a UK multicentre randomised, placebo-controlled, double-blind feasibility trial with nested qualitative study

Objective

To determine the feasibility of a definitive trial of metformin to prevent type 2 diabetes in the postnatal period in women with gestational diabetes.

Design

A multicentre, placebo-controlled, double-blind randomised feasibility trial with qualitative evaluation.

Setting

Three inner-city UK National Health Service hospitals in London.

Participants

Pregnant women with gestational diabetes treated with medication.

Interventions

2 g of metformin (intervention) or placebo (control) from delivery until 1 year postnatally.

Primary outcome measures

Rates of recruitment, randomisation, follow-up, attrition and adherence to the intervention.

Secondary outcome measures

Preliminary estimates of glycaemic effects, qualitative exploration, acceptability of the intervention and costs.

Results

Out of 302 eligible women, 57.9% (175/302) were recruited. We randomised 82.3% (144/175) of those recruited, with 71 women in the metformin group and 73 women in the placebo group. Of the participants remaining in the study and providing any adherence information, 54.1% (59/109) took at least 75% of the target intervention dose; the overall mean adherence was 64% (SD 33.6). Study procedures were found to be acceptable to women and healthcare professionals. An increased perceived risk of developing type 2 diabetes, or a positive experience of taking metformin during pregnancy, encouraged participation and adherence to the intervention. Barriers to adherence included disruption to the medication schedule caused by the washout periods ahead of each study visit or having insufficient daily reminders.

Conclusions

It is feasible to run a full-scale definitive trial on the effectiveness of metformin to prevent type 2 diabetes in women with gestational diabetes, during the early postnatal period. Adherence and engagement with the study could be improved with more regular reminders and potentially the addition of ongoing educational or peer support to reinforce messages around type 2 diabetes prevention.

Trial registration number

ISRCTN20930880.

Project 20: Midwives’ insight into continuity of care models for women with social risk factors: What works, for whom, in what circumstances, and how

Women with social risk factors such as those living in poverty and social isolation, seeking asylum or refugee status, experiencing domestic abuse, mental illness, learning difficulties, and substance abuse problems, have significantly higher rates of poor birth outcomes compared to their more advantaged counterparts (Draper, 2019, Biro, 2017, Lindquist, 2015, Blumenshine, 2010, Smith 2009). In both the UK and the US women from black and minority ethnic backgrounds [BME] also experience unacceptably high rates of morbidity and mortality compared to their white counterparts, regardless of their socio-economic status (Knight et al, 2018).