In general terms, risk is the probability that an event will happen. When talking about cancer, risk is most often used to describe the chance that a person will develop cancer or have a recurrence. Knowing this information not only helps the patient make more informed decisions about their health, it also helps researchers improve the health of large numbers of people. A risk factor is anything that increases a person’s likelihood of developing cancer. Although risk factors, such as smoking or a family history of cancer, often influence the development of cancer, most do not directly cause cancer.
Some people with several risk factors never develop cancer, while others with no known risk factors do. However, knowing the risk factors can help a person to make more informed lifestyle and health care choices. Now, a study from researchers at Karolinska Institutet and University of Stockholm has shown that the risk of developing cancer increases with height in both Swedish men and women. The team state that this long-term study is the largest carried out on the association between height and cancer in both genders. The findings were presented at the 54th Annual European Society for Paediatric Endocrinology Meeting.
Previous studies show that general risk factors for cancer include older age, a personal and/or family history of cancer, using tobacco, some types of viral infections such as human papillomavirus or HPV, specific chemicals, and exposure to radiation including ultraviolet radiation from sunlight. Although risk factors like using tobacco, being overweight, and getting multiple sunburns can be avoided, other risk factors cannot be controlled, such as getting older.
Earlier studies have also shown an association between height and cancer, with findings showing that taller individuals have a higher risk of developing different types of cancer, including breast cancer and melanoma. However, the team state that this association has never been studied in men and women on such a large scale before. They go on to add that to their knowledge, this is the largest study performed on linkage between height and cancer including both women and men.
The current study examined 5.5 million men and women in Sweden, born between 1938 and 1991 and with adult heights ranging between 100 cm and 225 cm. The group followed the participants from 1958, from the age of 20, until the end of 2011. The results showed that for every 10 cm of height, the risk of developing cancer increased by 18% in women and 11% in men. Additionally, data findings show that taller women had a 20% greater risk of developing breast cancer, whilst the risk of developing melanoma increased by approximately 30% per 10 cm of height in both men and women.
The lab explain that the data on adult heights was collected from the Swedish Medical Birth, the Swedish Conscription, and the Swedish Passport Registers, whereas the cancer data was retrieved from the Swedish Cancer Register. The team note that their results reflect cancer incidence on a population level. They go on to conclude that as the cause of cancer is multifactorial, it is difficult to predict what impact these results have on cancer risk at the individual level.
The researchers surmise that their study shows that taller individuals are more likely to develop cancer, however, it is unclear so far if they also have a higher risk of dying from cancer or have an increased mortality overall. For the future, the group is now planning on investigating how mortality from cancer and other causes of death are associated with height within the Swedish population.
Source: BioScientifica Limited