Impact of early psychosocial factors (childhood socioeconomic factors and adversities) on future risk of type 2 diabetes, metabolic disturbances and obesity: a systematic review

Abstract

Background: Psychological factors and socioeconomic status (SES) have a notable impact on health disparities, including type 2 diabetes risk. However, the link between childhood psychosocial factors, such as childhood adversities or parental SES, and metabolic disturbances is less well established. In addition, the lifetime perspective including adult socioeconomic factors remains of further interest.We carried out a systematic review with the main question if there is evidence in population- or community-based studies that childhood adversities (like neglect, traumata and deprivation) have considerable impact on type 2 diabetes incidence and other metabolic disturbances. Also, parental SES was included in the search as risk factor for both, diabetes and adverse childhood experiences. Finally, we assumed that obesity might be a mediator for the association of childhood adversities with diabetes incidence. Therefore, we carried out a second review on obesity, applying a similar search strategy.

Methods: Two systematic reviews were carried out. Longitudinal, population- or community-based studies were included if they contained data on psychosocial factors in childhood and either diabetes incidence or obesity risk.

Results: We included ten studies comprising a total of 200,381 individuals. Eight out of ten studies indicated that low parental status was associated with type 2 diabetes incidence or the development of metabolic abnormalities. Adjustment for adult SES and obesity tended to attenuate the childhood SES-attributable risk but the association remained. For obesity, eleven studies were included with a total sample size of 70,420 participants. Four out of eleven studies observed an independent association of low childhood SES on the risk for overweight and obesity later in life.

Conclusions: Taken together, there is evidence that childhood SES is associated with type 2 diabetes and obesity in later life. The database on the role of psychological factors such as traumata and childhood adversities for the future risk of type 2 diabetes or obesity is too small to draw conclusions. Thus, more population-based longitudinal studies and international standards to assess psychosocial factors are needed to clarify the mechanisms leading to the observed health disparities.

Figure 1

Flow diagram of systematic review on type 2 diabetes incidence and on obesity.

Figure 2

Impact of low SES influencing the incidence of type 2 diabetes. Effect sizes given as OR, HR or RR (central point) flanked by lower and upper 95% CI (results of high SES have been inverted, x-axis ends with 8, end points of higher results are not shown). Results of D8 and D9 are given as β-coefficients and are not included in Figure 2. D8 shows no effect of low SES; in D9 a considerably higher risk for type 2 diabetes incidence in the low SES group can be concluded.

Figure 3

Impact of low SES influencing overweight and obesity. Effect sizes given as OR, HR or RR (central point) flanked by lower and upper 95% CI. Results of O6, O7, and O12 are given as β-coefficients and are not included in Figure 3. In O6 a limited effect of low SES is seen; in O7 and O12 a considerably higher risk for type 2 diabetes incidence in the low SES group can be concluded.