Browsing by Subject "early life stress"

Goals As the proportion of the elderly population increases, studying biomarkers of cellular aging have become an important focus of research. However, these risk factors of age-related diseases have been difficult to identify. Recently an estimator of cellular aging, based on DNA methylation levels, the DNAm age, has been developed, and it has been linked to risk for both greater mortality and physical and mental health diseases. Effects of early life stress and later health on DNAm age have not yet been studied together. We set out to study, if early life stress and later quality of life and depression each separately or in combination associate with DNAm age. Methods The participants comprised Finnish males, of which 83 were separated from their families during the World War 2, and 83 non-separated controls belonging to the Helsinki Birth Cohort Study. Genome-wide methylation profiles, Rand-36 quality of life and BDI-1 depression inventory were assessed during years 2001-2004. DNAm age was estimated using the Horvath procedure. Associations of separation status, Rand-36 scores and BDI scores on DNAm age were studied with linear regression after adjusting for chronological age, cell type counts, tobacco smoking and frequency of alcohol consumption. Results and conclusions The separation status did not associate with the DNAm age. The Rand-36 Bodily Pain –scale associated differently with DNAm age in the separated group compared to the non-separated group. In analyses stratified for separation status, mild-severe depressive symptoms associated with lower DNAm age in the separated group. Similarly, lower quality of life on Rand-36 Role Functioning-scale and Emotional and Role Functioning Physical -scale associated with lower DNAm age in the separated group. Results are in line with previous studies, which have shown that early life stress doesn't associate with the DNAm age, but the cumulative total life stress and later adulthood diseases do associate with the DNAm age. This study brings novel information of the associations of early life stress and later depression symptomatology and psychosocial quality of life on the DNAm age, and suggests the early life stress and later depression and poorer psychosocial quality of life to have a cumulative effect on the DNAm age. More studies and longitudinal follow-up is needed to clarify the role of DNAm age as a biomarker of cellular aging, especially when examining the effects of early life stress exposure and later health together.