Biological and psychological protective factors against the intergenerational transmission of criminal convictions: A total population, sibling comparison study

Parental criminality is a risk factor for crime, but little is known about why some individuals exposed to this risk refrain from crime. We explored associations of resting heart rate (RHR), systolic blood pressure (SBP), cognitive ability (CA), and psychological functioning (PF) with criminal convictions among men with a convicted parent, accounting for unmeasured familial factors in sibling analyses. Data were obtained from Swedish registers, including all men born in Sweden between 1958 and 1992 with a convicted parent (<i>N</i> = 495,109), followed for up to 48 years. The potential protective factors were measured at mandatory conscription. Outcomes were conviction of any, violent, and non-violent crime. Survival analyses were used to test for associations, adjusting for measured covariates and unmeasured familial factors. Higher levels of RHR, SBP, CA, and PF were associated with reduced risk of criminality after adjusting for covariates. RHR associations were largely explained by familial factors. CA and PF associations were not due to sibling-shared confounders, in line with a causal interpretation. SBP results, indicating a protective effect against non-violent crime, warrant further investigation.