What to know about potential risk factors for AML

AML can happen at any age. However, it is more common in adults aged 60 and above, with AML having a median age of 70 years old. With increasing age, people are more likely to experience gene changes, which may explain why AML usually occurs in older adults.

AML is more common in males, regardless of age. However, the reason for this is not clear. A 2017 study suggests that many gene mutations occur on the X chromosome, damaging genes that can stop cell overproduction that may result in cancer. Women may have more protection from developing AML because they typically have two functioning copies of these genes, while men usually only have one copy.

Smoking is a known risk factor for several types of cancer. Not only does it affect cells that come in direct contact with smoke, causing lung and mouth cancers, but cancer-causing substances absorbed by the lungs can also spread through the bloodstream and reach other parts of the body.

A 2014 study found that current smokers have a 40% increased chance of developing AML, while people who have ever smoked in the past have a 25% increased chance, when compared with non-smokers.

Exposure to certain chemicals, like benzene, also increases a person’s risk of AML. According to the Centers for Disease Control and Prevention (CDC), benzene is a commonly used industrial chemical in the United States. that is present in cigarette smoke, rubbers, dyes, and pesticides. Evidence indicates that long-term exposure can cause leukemia.

Benzene is known to alter cell function and induce blood cancers. A 2020 study found that benzene exposure has a 7-fold risk for developing leukemia and benzene poisoning has a 71-fold risk of causing AML. Researchers also found that prolonged benzene exposure led to a rapid leukemic mutation of cells in mice.

Many individuals with other cancers, such as solid tumors, who receive treatment with certain chemotherapy drugs, like alkylating agents, may be more likely to develop AML years after their initial treatment. Likewise, a 2021 study says that people may not detect secondary AML during some treatments, but it may appear after a person starts receiving chemotherapy.

People who have chemotherapy are also at risk of having clonal hematopoiesis, an age-related disease that can cause an overproduction of blood precursor cells.

Exposure to high doses of radiation, including radiation therapy for cancer, increases a person’s risk of AML.

A 2020 study states that radiation exposure causes gene abnormalities similar to alkylating agents, most commonly in chromosomes 5 and 7. The study also notes that people who acquire therapy-related cancers from radiation exposure have poorer outcomes, despite intensive treatments.

Other conditions, especially blood disorders, including myeloproliferative disorders (MPD) and myelodysplastic syndromes (MDS), tend to develop into AML. Chronic MPDs include idiopathic myelofibrosis, essential thrombocytopenia, and polycythemia vera.

An older review also suggests an association between AML and autoimmune diseases, like rheumatoid arthritis, systemic lupus erythematosus, and polymyalgia rheumatica. Autoimmune diseases may increase the risk of developing AML due to the conditions having similar medications, shared genetic susceptibilities, and intrusion to the bone marrow.

The 2016 World Health Organization (WHO) classification of myeloid and acute leukemia recognizes AML as a condition with a hereditary predisposition. A person with a twin, sibling, or parents with AML has an increased chance of developing the condition.

Several genetic conditions may also increase the risk of developing AML:

• Down syndrome
• trisomy 8
• Fanconi anemia
• Bloom syndrome
• ataxia-telangiectasia (AT)
• neurofibromatosis type 1
• Kostmann syndrome, also called severe congenital neutropenia
• Diamond-Blackfan anemia
• Shwachman-Diamond syndrome
• Li-Fraumeni syndrome

Obesity is a known risk factor linked with many cancers, including blood cancers. This is because obesity creates a cellular environment that promotes accelerated cancer growth.

A 2017 meta-analysis found that people who are overweight or obese have a higher chance of developing AML. The article also mentions that high body mass index (BMI) can predict poorer outcomes in acute promyelocytic leukemia (APL), a subtype of AML.

A 2015 study states that obesity is a risk regardless of the timing of obesity.

Researchers continue to investigate other possible factors that may link to AML. While there are already several studies available, there is not yet sufficient evidence to suggest the factors studied may cause AML.

A 2017 study found that children who live near gasoline stations and have parents exposed to benzene are more likely to develop childhood leukemia. Both associations relate to the benzene content of these chemicals.

An older study found that exposure to extremely low-frequency electromagnetic fields (ELF-EMF) can increase the risk for childhood leukemia. Similarly, a 2018 meta-analysis notes that workers exposed to high levels of ELF-EMF for a longer duration had an increased risk of AML.

Pesticide exposure is also associated with childhood leukemia, especially AML.

A 2021 meta-analysis indicates that occupational pesticide exposure can increase the risk of AML.

AML is a bone marrow and blood cancer. While the exact cause of AML is unknown, evidence suggests there are multiple factors that can cause genetic changes and increase a person’s risk of developing AML. There are some risk factors that people cannot change, such as age and family history. However, people can try to reduce other risk factors, such as exposure to smoking and certain chemicals.