Data or Diamonds?
Danish health is unique. It covers the entire population on an individual level; it can be traced back to the 1960s, is extremely detailed, and covers many different types of health data from population surveys to laboratory data, to electronic patient records, and to structured national register data. For researchers, the possibility to study a certain illness, medication, or treatment is one of the reasons why Denmark also attracts the largest amount of clinical trials per capita in Europe.
In Denmark, we keep a register of information on all of our citizens – from education, civil status, to births and surgeries, to prescription medicine and hospital stays. Because every citizen has a personal and unique identification number, all this information from hundreds of different registers can be linked together on an individual level.
For Dr. Amani Meaidi, the high quality, the linkability, and the high level of detail of Danish health data became the ultimate companion for her Ph.D. thesis.
With the help from Danish health data registers, she was able to follow women in Denmark between 1996 and 2017 to see, who was prescribed a certain drug to prevent heavy menstrual bleeding, and where the risk of thrombosis with this specific treatment was not studied to a large extend.
By using nationwide Danish health data registers, she was able to investigate the associations between use of the drug and the risk of deep-vein thrombosis or pulmonary embolism and arterial thrombosis in the heart or brain. The research cohort consisted of Danish women aged 15 to 49 in the period of 1996 to 2017, which resulted in the possibility to follow around 2 million Danish women in 14 million person-years. Because of the large empirical foundation, her sample consisted of more than 60,000 women, who had been prescribed the drug and more than 7,000 cases of thrombosis during the period.
Video Watch Amani explain how you can use Danish health data for your clinical trials
Faster, cheaper and more ethical
Prior to this study, Dr. Meaidi had discovered that previous randomized controlled trials, studying the effect of the drug on heavy menstrual bleeding, had only been completed with just a few hundred women. Dr. Meaidi agreed that a randomized controlled trial on the risk of thrombosis from the use of the drug would be unethical, if it meant exposing otherwise healthy women to the possibility of thrombosis, and altogether very costly and time consuming. With the use of already existing Danish health data registers, Dr. Meaidi and her team was able to examine the same research question approximately as well as with a randomized controlled trial, but more ethically sensible, cheaper, faster, and with a much larger cohort.
“In Denmark, we don’t have diamonds in the ground. We have data in the cloud”
With the completion of the study, it became the first nationwide cohort study on the influence of the drug for heavy menstrual bleeding on the risk of thrombosis. Besides the extensive health data, they were able to link each individual in the study to other socioeconomic characteristics such as educational level and smoking status, and hereby accounting for a wealth of possible confounding factors.
The study by Dr. Meaidi and her team is a textbook example of how Danish health data can be applied to develop and optimize the field of medicine, not just for Danes, but for every citizen of the world.