A unique study using epigenetic markers to track biological aging has found prematurely born males, of extremely low birth weight, seem to age more rapidly than prematurely born females with similar birth weight. Why this is the case is unclear but the research suggests the health of male preterm survivors should be closely monitored across their life.
For several decades scientists have noted premature low birthweight boys have significantly more postnatal complications than girls. This new research investigates the phenomenon by analyzing data from the world’s longest running study of extremely low birth weight (ELBW) babies. The cohort includes 45 ELBW babies, tracked up to the age of 30 to 35, compared to a similarly aged control group born with normal birth weight.
To measure aging the researchers utilized a recently developed technique that analyzes DNA methylation, genetic markers than accumulate as we get older. This kind of epigenetic clock has been found to offer a biologically meaningful and objective measure of aging.
The research found those premature males in their mid-30s were 4.6 years older than similarly aged males born with normal birth weight. No difference in biological aging between ELBW and normal weight babies, according to the epigenetic measures, was detected in the female cohorts.
"Although it is unclear why accelerated biological aging is seen in the ELBW men, this suggests that prenatal exposures play an important role in aging," notes first author Ryan Van Lieshout.
This is the first study to look at this kind of accelerated aging measure in prematurely born subjects and in some ways it raises more questions than it answers. It is unknown exactly what environmental triggers could be influencing these epigenetic markers and it is even more unclear why it seems to affect men more than women.
As this is a single, relatively small observational study the researchers do call for larger investigations into the possibility of accelerated biological aging in prematurely born males. In the short term, however, Van Lieshout says these findings affirm the importance of ELBW males adopting lifestyles that accentuate healthy aging. He notes good diet, exercise and proper sleep can all reduce some of the risks of accelerated aging.
"This certainly highlights the need to monitor the health of preterm survivors across their lifespan, and more research needs to be done," says Van Lieshout. "This also emphasizes the need to forewarn the ELBW men and promote healthy aging so they may proactively mitigate these risks."
The new study was published in the journal Pediatrics.
Source: McMaster University