Childhood Adversity Increases Risk of Adult Type 2 Diabetes

A new study published in Diabetologia (the journal of the European Association for the Study of Diabetes [EASD]) finds that people who experienced adversity in childhood have a higher risk of developing type 2 diabetes (T2D) in early adulthood .

The research was conducted by Assistant Professor Leonie K. Elsenburg and colleagues in the Section of Epidemiology, Department of Public Health, University of Copenhagen, Copenhagen, Denmark, and aimed to determine whether there was a link between childhood adversity and development of T2D in early adulthood (16-38 years) among men and women.

The global prevalence of T2D among adolescents and young adults has increased substantially over the last century, driven primarily by changes in lifestyles and obesity rates. This is particularly concerning because early onset of the disease (before age 40) appears to have more aggressive pathology, and affected individuals are of working age, may require lifelong treatment, and face a higher risk of complications. These factors combined make the identification of risk factors for T2D in early adulthood an issue of crucial public health importance.

Childhood adversity can involve experiences such as maltreatment, physical or mental illness in the family, and poverty and has been associated with the development of diabetes even in young adults.

Adverse events and circumstances can trigger physiological stress responses and affect the behavior of the nervous system, hormones, and the body’s immune response. They can also affect mental well-being and lead to behavioral changes that negatively affect health, such as poor sleep, smoking, reduced physical activity and sedentary behavior, increased alcohol consumption and unhealthy eating, which can lead to obesity and a high risk of developing T2D.

Previous research has revealed an association between childhood maltreatment and the development of T2D in young adulthood, but evidence for a link with other types of adversity is scarce and sex-specific estimates are lacking. The authors also note: "There is a need for methodological improvements in this area of ​​research, including the need for prospective studies using objective, more comprehensive measures of childhood adversity."

The researchers used data from the Danish Life Course Cohort Study (DANLIFE) which includes the childhood history and adversities of children born in Denmark since January 1, 1980. To allow follow-up from age 16 onwards, the The study sample was limited to those individuals born through December 31, 2001 and excluded people diagnosed with diabetes in childhood, those with insufficient data on covariates, and anyone who emigrated or died before age 16.

This study population was divided into five childhood adversity groups based on annual counts of exposure (ages 0 to 15 years) to adversities in each of three dimensions: material deprivation (family poverty and long-term unemployment of parents), loss or threat of loss (somatic illness of parents, somatic illness of siblings, death of parents, death of siblings), and family dynamics (foster placement, psychiatric illness of parents, illness sibling psychiatric disorder, parental alcohol abuse, parental drug abuse, and maternal separation).

In these five groups, children experienced: 1. relatively low levels of childhood adversity (54%); 2. material deprivation specifically in early childhood (20%); 3. material deprivation throughout childhood and adolescence (13%); 4. relatively high levels of somatic illness or death in the family (9%); and 5. relatively high levels of adversity in all three dimensions (3%).

Of the study population of 1,277,429, a total of 2,560 women and 2,300 men developed T2D during follow-up, which lasted an average of 10.8 years. The authors found that, compared to the "Low Adversity" group, the risk of developing T2D in early adulthood was higher in all other adversity groups, for both men and women. In the “High Adversity” group, which was characterized by high rates of adversity in all three dimensions, the risk of developing diabetes was 141% higher in men and 58% higher in women, which translates by 36.2 and 18.6 additional cases per 100,0000 person-years among men and women, respectively.

After adjusting for parental education level, size for gestational age, and preterm birth, effect estimates were reduced, particularly for women in the "High Adversity" group. Compared to their counterparts who experienced little adversity during childhood, their additional risk of developing T2D was reduced from 58% to 23%, translating to 6.4 additional cases per 100,000 person-years instead of 18.6 per 100,000 person-years. Most of the reduction in estimated risk was the result of adjustment for parental education level.

The authors found that the relative risks of developing T2D due to childhood adversity were lower among women than among men in all groups. Furthermore, the absolute effects (in terms of the number of additional cases of diabetes per 100,000 person-years) were also smaller among women than among men, except for experiencing material deprivation in childhood, where the absolute effect was comparable between men and women.

The study reveals that people exposed to childhood adversity, such as poverty, illness or death in the family, and dysfunctional homes have a higher risk of developing type 2 diabetes in young adulthood compared to those who experience low levels of adversity in childhood. These findings are reinforced by the large size of this population-based study, as well as its absence of selection or recall bias. Furthermore, the authors point out that there is a close relationship between parents’ education levels and their children’s experience of adversity, which explains part of the observed association.

The researchers conclude that a portion of T2D cases arising in adulthood could likely be prevented through early interventions that address the root causes of childhood adversity, to reduce or even eliminate its negative impact on children’s lives.