Causes and risk factors
We don’t know what causes CLL, but in recent years, many researchers have devoted themselves to the study of CLL to understand the causes of this form of leukemia.
Numerous studies have made it possible to understand some of the altered biological mechanisms that lead the CLL's lymphocytes to proliferate and live longer. Today it is known that some factors, in particular, some genetic alterations, all contribute together to ensure that these lymphocytes live longer and proliferate without there being a "right" reason. There are a number of factors that may increase the risk of developing it:
● Age. The risk of developing CLL increases with age. Most people with CLL are older than 60. It's rare in people under 40. The incidence of the disease increases from less than one per 100,000 in individuals aged 40 to 44 years to more than 30 per 100,000 in individuals aged 80 and older. Older patients tend to have a worse outcome due to being diagnosed with a more aggressive CLL and the inability to tolerate treatment and symptoms of the disease.
● Gender. CLL is more common in men than women.
● Family history. Most people with CLL have no family history of it. First-degree relatives of patients with CLL are three to four times more likely to develop CLL than people who do not have first-degree relatives with the disease. However, the risk is still small. For example, the 60-year-old sibling or child of someone with CLL would have three to four chances in 10,000 of developing the disease, compared with the one chance in 10,000 for a 60-year-old person without a family history of the disease.
● Ethnicity. CLL is most common in people of European origin.