When you are living with multiple sclerosis (MS), you may deal with other conditions as well. These are known as comorbidities. A comorbidity refers to a situation when two or more health conditions are present in the same individual at the same time. Neurological conditions, such as MS, are considered a heavy burden on a person. In particular, MS may be even more challenging given that it is often a relapsing disease. This makes understanding and dealing with the risks of MS-related illnesses all the more challenging.

What Conditions Are Comorbid With MS?

According to a systematic review that analyzed 249 articles and research papers, it is estimated that the most prevalent comorbidities in people living with MS are depression (23.7 percent), anxiety (21.9 percent), high blood pressure (18.6 percent), high cholesterol (10.9 percent), and chronic lung disease (10 percent).

Furthermore, it is estimated that approximately 30 percent of people with MS have autoimmune comorbidities. In one study, the most common autoimmune diseases in people with MS were thyroid disease (11.9 percent), asthma (5 percent), type 2 diabetes mellitus (4.9 percent), psoriasis (4 percent), and rheumatoid arthritis (2.7 percent). If you have an autoimmune disease such as one listed above, there is a slightly higher chance of developing MS. Additionally, it is thought that having MS also puts a person at increased risk of developing other autoimmune conditions.

In a 2016 report published in Neurology, one research team has outlined several guidelines to better understand MS comorbidities and increase the number of effective treatment options. First, the researchers recommend that incidence and prevalence rates be firmly established. Incidence relates to the number of new diagnoses of a specific comorbidity within a given time period. In contrast, prevalence refers to the number of people who have a specific comorbidity during a specific time period. More studies are needed to get a better picture of how many people with MS have new comorbidities or are living with them already.

Additionally, the prevalence of MS should be broken down by age and sex for comorbidities associated with the disease. Understanding these features is important in depression, anxiety, high blood pressure, high cholesterol, and diabetes. This research team also suggests that physicians and researchers evaluate the effect of MS comorbidities, such as the diseases listed above, on a variety of variables. These variables should include disability, quality of life, neurological outcomes, and mortality. Lastly, study designs should be more consistent in their methodology, and should include details about people living with MS from around the world. The ultimate goal of guidelines such as these is to increase the number of clinical trials aimed at treating comorbidities associated with MS.

The Burden and Impact of MS Comorbidities

Having both MS and a comorbid condition can greatly impact a person’s well-being and quality of life. It’s important to understand how these comorbidities affect treatment options and life span in those with MS, and whether they can worsen MS symptoms.

Cardiovascular Disease and Vascular Comorbidities

One study showed that participants with MS who had at least one comorbid cardiovascular risk factor (such as high blood pressure) had an increased number of brain lesions and more severe decreases in brain volume. Several factors play into cardiovascular disease risk, especially obesity. In this case, having comorbid cardiovascular issues worsened the outcomes of the MS population.

In another study, physical comorbidities such as ischemic heart disease and epilepsy were also associated with an increase in MS disability progression. In this same study, these relationships were also found to be linear. This means that with each additional comorbidity that the same person had in addition to their MS diagnosis, the greater the score they had on the Expanded Disability Status Scale (EDSS).

Another study conducted over a period of three years found that high blood pressure, diabetes, and obstructive lung disease (but not high cholesterol) impacted outcomes related to MS. Outcomes that were affected by these comorbidities included walking speed, self-reported disability, and depression.

Learn more about the connection between heart disease and MS.

Autoimmune Comorbidities

Autoimmune disorders also have their own complications when comorbid with MS. Research suggests that Graves’ disease, a hyperthyroidism disorder, significantly co-occurs with MS compared to the general population. Hasimoto’s disease, a hypothyroidism disorder, also has a relationship with MS. In another study of 286 participants, people who had MS and type 1 diabetes were more likely to have reductions in brain size or volume compared to people who had MS and another autoimmune disorder. These other autoimmune disorders included autoimmune thyroiditis and celiac disease.

Mental Health Comorbidities

Mental health comorbidities complicate MS just as much as physical comorbidities do. Some researchers assert that the treatment of anxiety and depression is actually an unmet need in people living with MS. A systematic review of many studies found that mental health disorder comorbidities (depression and anxiety disorders) remain undertreated in people with MS. They also found that psychiatric comorbidities, such as bipolar disorder, also went underrecognized in the health care setting.

Depression and anxiety are particularly underdiagnosed in people with MS. This may be because depression or anxiety can be symptoms of MS itself. MS and depression also share several symptoms, such as fatigue, poor concentration, and sleep problems, which makes it even harder to disentangle these disorders from one another.

Read more about depression and MS.

Sleep Disorder Comorbidities

Sleep disorders are diagnosed more frequently in people with MS compared to those in the general population. The matter is further complicated by the fact that the association between MS, poor sleep, fatigue, depression, and anxiety goes both ways. This means that while MS can lead to poor sleep, for example, poor sleep increases other symptoms of MS.

Obstructive sleep apnea is another disease for which people living with MS are at higher risk. Further, obstructive sleep apnea leads to increased fatigue, increased MS-related disability, and other health problems.

In short, comorbidities negatively affect outcomes throughout the disease course in MS. These negative outcomes include a delay in diagnosis from the time of symptom onset and increased disability at diagnosis. Comorbidities also affect cognitive abilities, mortality risk, and overall quality of life. Regular follow-up with your doctor or neurologist is necessary, and it is important to share with them whether you are experiencing any other health-related issues.

Read more about sleep disorders and MS.

Talk With Others Who Understand

MyMSTeam is the social network for people with multiple sclerosis and their loved ones. On MyMSTeam, more than 167,000 members come together to ask questions, give advice, and share their stories with others who understand life with multiple sclerosis.

Are you living with multiple sclerosis? Did any of these conditions come up as possible comorbidities on your path to diagnosis? Share your experience in the comments below, or start a conversation by posting on MyMSTeam.