What are the risk factors and complications of ALS?

What are the risk factors and complications of ALS?

ALS risk factors

The risk factors that have been established for ALS are the following:

  • Heredity – Roughly 5-10% of those who have ALS have inherited the condition, this is known as familial ALS. These people who have inherited ALS have a fifty-fifty chance of their children developing the condition.
  • Genetics – There have been some studies conducted that examined the human genome entirely (i.e. genome-wide association research), and found a number of similarities within the gene variations in those who have familial ALS as well as a few of those who have non-inherited ALS. These variations of genes may result in certain people being more at risk of developing ALS.
  • Age – The risk of ALS developing will increase with age and is most commonly seen in those who are in their 40s and older.
  • Gender – It has been noted that those who have the condition and are younger than 65 are more likely to be men than women. This sexual difference tends to disappear in patients over 70 years old.

It has also been documented that environmental factors may have a role to play in the risk factors of ALS. These risk factors include:

  • Exposure to environmental toxins – There has been some evidence that suggests the exposure to toxins such as lead in the home or workplace may have a link to the development of ALS. There have been a number of studies conducted to try and identify the exact kind of toxin exposure that increases one’s risk of ALS, but not one single chemical is yet to be identified.
  • Smoking – Smoking cigarettes is likely to be an environmental risk for ALS, this risk is especially greater for women and also increased after menopause.
  • Military service – There has been recent evidence that suggests that those who have completed military service could have an increased level of risk in developing ALS. It is still unclear as to why this link exists, although some research suggests that those in the military may be exposed to a number of chemicals, viral infections, traumatic injuries or undergo intense physical exertion that can play a role in disease development.

ALS complications

As ALS progresses, those who suffer from it may experience some of the below complications:

Breathing issues

In time, ALS will progress and paralyse the muscles needed for breathing. At this stage, the patient may require a breathing device that helps them to breathe during the night. This air can be given through a BiPAP (bi-level positive airway pressure) or via a CPAP (continuous positive airway pressure). Both of these devices are non-invasive pressure support ventilation systems that make use of a flow-cycled or time-cycled process that alternates between the two mechanically applied levels of positive airway pressure.

Patients who suffer from advanced ALS may opt for having a tracheostomy (also known as a tracheotomy) conducted, this is a surgery that will create a hole in the neck that leads to the trachea (windpipe) in order for a full-time respirator to be inserted. This respirator will inflate and deflate the lungs.

Respiratory failure is the most commonly attributed cause of ALS deaths which tend to occur between three and five years post initial symptoms onset.

Speech issues

The majority of patients who suffer firm ALS will start to have issues with their ability to speak once the condition begins to progress over time. Speech problems tend to begin as mild and occasional slurs of words, however, these can develop further to become far more severe. The patient’s speech will eventually become more and more difficult to understand which often results in the individual needing communication technologies in order for them to be understood and communicate. There are some computers and mobile phone applications that allow for patients to type in what they wish to say and the program will read it out loud. Certain phrases can also be selected in order for the patient to not have to type everything out.

More advanced programs are able to communicate with the patient without the patient having to type or try to speak, these work on Brain-Computer Interfaces that allow for the patient to control the computer through their brain waves, these require no movement and are often used for patients with advanced ALS suffering from paralysis.

Eating issues

Those with ALS may develop dehydration and malnutrition due to the damage done to the individual’s muscles needed for swallowing. These individuals also have an increased risk of developing pneumonia as liquids, food and saliva can get into their lungs as a result of their inability to swallow properly (this is known as aspiration). Thus, the introduction of a feeding tube may be necessary to aid in reducing these risks. This can also ensure that the patient does not suffer from dehydration and malnutrition.

Feeding tube


Some patients who have ALS may suffer from memory issues and battle to make decisions. This can lead to some of these individuals being diagnosed with frontotemporal dementia. Just to recap, this is a progressive disease that results in damage to the frontal lobes of the brain.

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