Well-known risk factors for asthma development include a family history of the disease, other allergic conditions, obesity, and smoking.

However, pharmacists should also be aware of the following lesser-known factors, which can increase patients’ likelihood of developing asthma or exacerbate their symptoms. 

1. Grandma’s smoking status
A grandmother’s smoking habits can contribute to her grandchild’s asthma risk, regardless of whether the mother smoked.

Recent research found that if grandmothers smoked while they were pregnant, the risk of asthma increased in grandchildren by 10% to 22%, even if the child’s mother did not smoke while she was pregnant.

The researchers said their next step is to determine whether the risk of asthma can also be inherited through the male family line.

2. Traffic pollution and smoke from fires
Asthma patients who are frequently exposed to heavy traffic pollution or smoke produced from wood fire heaters experience aggravated asthma symptoms, researchers have determined.

In their study, nearly 1500 asthma patients rated their exposure to wood fire smoke and heavy traffic pollution over the winter months. Those with higher exposure reported about 2 to 3 asthma flare-ups per week, while low-exposure patients reported about one flare-up per week.

Study author John Burgess noted in a press release that asthma patients should avoid living on busy urban streets.

3. Anxiety
In a study that mimicked asthma symptoms in patients, researchers from the University of Cincinnati determined that anxiety may aggravate symptoms of the disease.

The patients were instructed to breathe in and out through a coffee stirrer or narrow straw to imitate asthma attacks.

The participants with higher anxiety sensitivity reported greater anxiety during the straw-breathing tasks. The same population experienced greater asthma symptoms and decreased lung function during the tasks.

Based on these results, the researchers recommended anxiety sensitivity interventions like exposure therapy to reduce anxiety symptoms in asthma patients.

4. Exposure to drug problems or domestic violence
Children who are exposed to even just one adverse childhood experience face a 28% greater likelihood of developing asthma than peers who do not experience an adverse event in childhood.

Examples of adverse childhood events are domestic violence, drug problems, divorced or separated parents, the death of a parent, parents’ drug or alcohol dependence, or parents’ depression or mental illness.

Children exposed to 5 or more adverse childhood experiences had an asthma incidence rate of 25%, compared with 12% of children who were exposed to no adverse events.