Cardiovascular disease in individuals with a history of out-of-home care: a Swedish national cohort study
Authors: Hjern Anders , Brännström Lars , Vinnerljung Bo , Frank Philipp , Batty G. David 
Published: January 2023

Background

Individuals with a history of out-of-home care in childhood experience elevated rates of mortality from all-causes and suicide in adulthood but the relationship with chronic disease is unknown. We examined the association between out-of-home care and cardiovascular disease (CVD) in a large cohort study and, in the women, explored how care is embodied to give rise to CVD.

Methods

This is a cohort study generated from linkage of a range of Swedish national registers. Born 1972-1981, 447,516 men (12711 with a care background) and 415,910 women (11926 with a care background) were followed between care graduation at age 18 and up to age 48 years for hospitalisations and death. A subgroup of 377,500 women (87% of the birth cohort) were linked to a maternity database which yielded data on adult cigarette smoking and metabolic risk factors.

Results

A maximum of 30 years of health surveillance gave rise to 5519 CVD events (2049 in women). After adjusting for the confounding factors of year of birth and maternal education, men (hazard ratio 1.95 [95% CI 1.68-2.25]) and women (1.80 [1.48-2.18]) with a history of out-of-home care in childhood had around a doubling of CVD risk in adulthood compared with general population controls. Separate presentations of CVD, such as myocardial infarction and stroke, revealed similar magnitudes of association with care. In women who had given birth, adjustment for the mediating variables of adult smoking status (1.41 [1.12-1.78]) and educational performance (1.57 [1.25-1.98]), but not metabolic risk factors (1.98 [1.24-3.15]), led to marked attenuation in CVD risk.

Conclusion

In the present study, men and women separated from their family of origin in early life experienced an increased burden of CVD as adults. Results for women suggest that targeting health behaviours, teenage pregnancy, and educational performance in these groups may potentially mitigate risk. These findings add to the array of adverse adult health outcomes seemingly experienced following care graduation.

Results in Context

Evidence before this study

It is becoming increasingly well established that people who experience periods of state (out-of-home) care in childhood have an elevated risk of unfavourable social, economic, and psychological outcomes in adult life, some of which are themselves known risk factors for CVD. Moreover, higher rates of mortality from all-causes relative to general population controls have also been reported, so raising the suggestion that care is linked to later chronic disease. A search of PubMed and Embase using a variety of terms for out-of-home care (e.g., state care, public care, looked-after) and chronic disease (cardiovascular disease, heart disease, stroke, cancer) did not identify any relevant studies.

Added value of the study

For the first time to our knowledge, we examined the association between a history of out-of-home care in early life and adult CVD. In a large cohort of men and women generated from a series of linkages to administrative datasets, after taking into account confounding factors, we found that those with a history of childhood out-of-home care experienced a doubling of the risk of adult CVD. For women for whom we had mediating data from adulthood, there was a suggestion that this effect was explained by low maternal age at birth of offspring, cigarette smoking, and socioeconomic disadvantage in later life.

Implications of all the available evidence

Interventions designed to target the prevention of smoking, teenage pregnancy, and sub-optimal educational achievement might have potential for CVD risk reduction in women with a pre-adult record of out-of-home care.