In recent years, scientists have realized that there is a need for more diversity in research. Studies are often conducted on male animal models, for example. New work has shown that gender disparities extend to the clinic as well. Women tend to get diagnosed for a particular disease later in life than men with the same disease do. This work, which used data from Danish people, showed that women not only get their diagnosis later than men, the care they receive is different. The findings have been reported in Nature Communications.
“When we look across all diseases, we see a tendency that women on average are diagnosed later than men. We have looked not just at diseases, but also at the course of the patient care. Our study zooms in on the areas where the differences are most pronounced - both for the individual diseases and for the course of the patient care. The message is that the national strategies that are established need to take a difference into account. We can no longer use the 'one size fits all' model. We are already heading in that direction with respect to personalized medicine,” explained the senior author of the work, Professor Søren Brunak of the Novo Nordisk Foundation Center for Protein Research.
Data from 6.9 million people, collected from 1994 to 2015, was utilized in this work. The scientists looked at the diagnosis of disease or diseases in patients, and the care they got. For 770 disorders, women were diagnosed four years later than men on average. Women got cancer, substance abuse, and metabolic disorder diagnoses later. These differences were not explained by direct anatomical or genetic factors.
With ADHD, boys were diagnosed around age 14 while it wasn’t until age 20 that women were diagnosed. The investigators note that this highlights the need for research that looks at disease subtypes affecting different genders; women tend to have a different subtype of ADHD that manifests as a solitary, quiet manner, unlike boys. One exception in which men were the ones diagnosed late was osteoporosis; men often didn't know they had the illness until they got a fracture.
There may be many reasons for these differences that include environmental, genetic, or diagnostic factors. The researchers are looking at these influences as a next step.
“It has been surprising to see that there is such a big difference between the diseases that affect men and women and between their patient care courses in a society where otherwise, we have equal and uniform access to the healthcare system. Now we are trying to map out what really lies behind the differences we see. Can they, e.g., be attributed to genetics or environment and culture?” Suggested the first author of the study, postdoctoral fellow David Westergaard of Novo Nordisk Foundation Center for Protein Research.
This work has illustrated the importance of gender variability in research studies, though it presents many challenges.
“But we need to think about the fact that there may be a sex difference right from the beginning at the hospitals and in the research. Traditionally, e.g. 50 men and women will be recruited for clinical trials. Afterwards, you look at the overall effect for the test participants. But you forget to make a subanalysis, where you look at the groups separately to see if there are differences. This has only been done during recent years,” added Westergaard.
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