Birth Month and Disease Risk
A fascinating new report by Columbia University Medical Center scientists has concluded that the month of one’s birth—at least in the New York City area, where patient’s records were examined—is weakly linked to one’s risk of developing various diseases later in life. It sounds like a modern version of astrology—the ancient practice that seeks to find order and patterns in life based on the configuration of the stars and planets in the heavens at the time of one’s birth. But the present findings were generated using powerful computers. Using a special algorithm, computers sifted through New York-area medical databases looking for patterns. Apparent associations between birth month and one’s risk of developing certain diseases emerged.
Researches think these associations may be due to seasonal changes in sunlight or temperature, which somehow affect a developing baby’s longterm health risks. So which month is fairest of them all in terms of future health risk? May. And worst? October. At New York’s latitude, May is the month when sunlight is finally growing stronger after a long winter. Since sunlight affects the production of vitamin D, and vitamin D affects multiple systems in the body, it’s conceivable that a mother’s and/or her fetus’ vitamin D status near the time of birth may somehow affect the baby’s developing immune system. In the Northern Hemisphere, October is the month when sunlight becomes too weak to spark the generation of vitamin D in the body. Production remains low to nonexistent throughout the winter.
Although it sounds too fantastical to believe, researchers believe they’ve uncovered evidence of genuine associations between birth month and future disease risk. But don’t put too much stock in something you can’t change anyway, investigators caution. "It's important not to get overly nervous about these results because even though we found significant associations the overall disease risk is not that great," notes senior author Nicholas Tatonetti, PhD. "The risk related to birth month is relatively minor when compared to more influential variables like diet and exercise."
According to the study’s findings, being born in late winter (March) puts you at risk for the heart rhythm abnormality, atrial fibrillation, and the cardiovascular disease process, atherosclerosis. Those born in September are more susceptible to asthma, and a November birth is linked to greater risks of viral infection and acute bronchiolitis (inflammation of the airways). Remarkably, some of the associations identified have previously been reported by other researchers. for example, both this study and an earlier Swedish study concluded that an ADHD diagnosis correlates with a November birth.
M. R. Boland, Z. Shahn, D. Madigan, G. Hripcsak, N. P. Tatonetti. Birth Month Affects Lifetime Disease Risk: A Phenome-Wide Method. Journal of the American Medical Informatics Association, 2015; DOI: 10.1093/jamia/ocv046