Understanding Light Sensitivity in Autoimmune Diseases, Lyme, and COVID-19
We’ve talked extensively about migraine light sensitivity in other articles, but the fact is, photophobia isn’t exclusive to migraineurs. Outside of migraine, it is a common symptom that occurs alongside migraine-like headache in a range of autoimmune diseases, Lyme disease, and even as a manifestation of COVID-19. In this article, we’ll shed some light on the presence of photophobia in many of these conditions and explore how narrow-band green light may be a source of soothing relief.
Light Sensitivity in Autoimmune Diseases
There are several known autoimmune diseases, and it would be nearly impossible to cover each and every one of them in this article. Below, we’ll speak to some of the most well-known conditions - fibromyalgia, multiple sclerosis, and lupus - exploring their documented associations with photophobia.
Fibromyalgia Light Sensitivity
Fibromyalgia is a well-described and common disorder that is still poorly understood at the physiological level. It is believed to reflect dysregulation in the pain-modulating systems of the brain. As with people who suffer from other pain disorders, fibromyalgia patients experience generalized sensory hypersensitivity — or to put it more simply, increased sensitivity to sights, smells, and even everyday light.
In a 2017 article published in Pain, researchers found that people with fibromyalgia express discomfort at substantially lower levels of light than a healthy population of the same age. This confirms data from an earlier study published in 2009, which found that while only 6% of healthy participants experienced photophobia, 70% of participating fibromyalgia patients reported persistent sensitivity to light.
Multiple Sclerosis Light Sensitivity
Multiple sclerosis (MS) is a chronic disease in which the immune system attacks the fatty substance insulating healthy nerve fibers, known as the myelin sheath. The resulting inflammation disrupts nerve cell processes and alters electrical messages in the brain. This can present itself in many ways, from muscle twitches and spasms to changes in vision. In fact, one of the primary ways MS presents itself in its early onset is through disruptions in vision, usually in a single eye, due to inflammation of the optic nerve, known as optic neuritis.
A 2018 study published in Multiple Sclerosis and Related Disorders found that photophobia has a higher prevalence in MS patients when compared to healthy controls. Surprisingly, previous optic neuritis or clinical disability did not predict which patients suffered from light sensitivity, indicating that a different physiological mechanism could be at play.
Lupus Light Sensitivity
Like multiple sclerosis, systemic lupus erythematosus (SLE) is a chronic autoimmune disease that impacts many systems within the body. Up to one third of SLE patients experience ocular complications; as in MS, ocular impairment can be one of the initial manifestations of lupus. These ocular complications can include skin or muscle changes around the eye, scleritis, retinal lesions, and even vision loss.
In many cases, lupus patients are negatively impacted by excessive sun exposure, which can result in skin rashes, fatigue, and even pain. This sensitivity to ultraviolet rays is known as Photosensitivity. It is more commonly documented in lupus than photophobia and is generally considered to be a direct symptom. It’s important to understand that photosensitivity is distinct and different from photophobia, which refers specifically to visual light sensitivity that is not exclusive to UV rays.
Nevertheless, many lupus patients do experience photophobia. A 2001 article published in Headache points toward one possible reason, reporting that of the 62% of participating lupus patients in the study who experienced frequent headaches, 39% met the criteria for migraine. Photophobia is all too common in migraine and is typically considered one of the most common and debilitating hallmarks of a migraine headache. This may explain why some lupus patients also experience photophobia.
Certain treatments for lupus can also contribute to photophobia: consistent, long-term treatment with hydroxychloroquine may cause adverse ocular reactions, including light sensitivity.
Is Autoimmunity on the Rise?
According to an April 2020 study published in Arthritis and Rheumatology, indicators of autoimmunity are on the rise amongst Americans. Researchers found an increase in the number of Americans with positive antinuclear antibody (ANA) blood tests over the past two decades. ANA is a type of antibody that can work against and even attack the body’s own cells, leading to autoimmunity — which in turn can result in autoimmune diseases such as lupus.
In the study, 11% of the blood samples collected between 1988 and 1991 showed a positive ANA result. However, that percentage rose to 15.9% when looking at samples collected between 2011 and 2012. Researchers suggest that environmental factors and lifestyle changes are likely driving the increase, and it’s not yet clear whether this rise in autoimmunity indicators has resulted in a similar rise in autoimmune diseases.
Lyme Disease Light Sensitivity
Lyme disease is caused by bacteria (Borrelia burgdorferi and Borrelia mayonii) that are spread through the bite of an infected tick. If left untreated, Lyme can spread to joints, the heart, and the nervous system in the second (early disseminated) and third (late disseminated) stages. In these later stages, Lyme is able to affect the central nervous system in multiple ways, including Lyme meningitis, causing a variety of neurological symptoms which range from memory impairment to photophobia.
One paper estimates that while photophobia only occurs in about 5% of early Lyme disease cases, it is a symptom for almost 40% of patients who develop Lyme meningitis. In a separate study, 70% of patients who reported Lyme-related neurological disturbances experienced photophobia, with severity ranging from uncomfortable to debilitating. Several patients reported feeling faint or dizzy when exposed to bright light, while others even noted that bright light triggered panic attacks.
Photophobia and COVID-19
In addition to the symptoms we most often associate with COVID-19 (headache, fever, and persistent cough), the virus can cause several other more unusual symptoms, including eye irritation and light sensitivity. One study, published in October of 2020, reported that 68 out of 144 survey respondents who tested positive for COVID-19 also experienced at least one overlapping eye symptom. Of those respondents, 13.9% experienced photophobia and 26.5% reported persistent eye symptoms beyond the course of the illness. Does this mean that COVID-19 could lead to long-term photophobia for certain people?
With the virus being so new, we simply don’t have the data we need to truly understand the long-term impacts of COVID-19 and draw such a conclusion. In the interim, sources such as case studies from physicians can point us toward what those answers may be.
Headache expert Dr. Robert Belvis suggests that COVID-19 consists of two phases, each of which is associated with a different type of headache. In the second phase, some patients may experience a migraine-like headache due to a cytokine storm. During a cytokine storm, too many cytokines (proteins that prompt cells to communicate) are released into the bloodstream when the immune system “overshoots” a healthy response. The overabundance of cytokines can lead to an overactive system, resulting in symptoms such as inflammation, fever, and migraine-like headaches. One case study even suggests that, in rare cases, migraine-like headache and photophobia may persist beyond the course of the virus.
The Soothing Effects of Narrow-Band Green Light
Why does photophobia occur in migraine and migraine-like headache? The answer eluded researchers until 2010, when Dr. Rami Burstein led a pinnacle study. By studying blind patients with migraine, he and his team realized that participants could be split into two groups: those who could still sense light and those who couldn’t. Surprisingly, for those who could still sense light, its presence made their migraines more painful during an attack. This pointed the team toward a previously undiscovered pathway connecting the retina to the area of the brain that interacts with those neurons that are most active during migraines.
Encouraged by this discovery, Dr. Burstein and his team set out to better understand how different colors of light interact with the migraine experience. They found that white, blue, amber, and red lights exacerbated not only photophobia, but other symptoms of an attack as well. Perhaps more interesting, however, was the discovery that a single, narrow band of green light interacted differently. It actually soothed the intensity of the headache, including photophobia and related symptoms.
This discovery gave rise to the concept of narrow band green light therapy, which has shown promise in a number of applications — some of which expand beyond migraine. Notably, in one study published in November of 2020, researchers found that fibromyalgia patients exposed to green light-emitting diodes reported a significant reduction in average pain intensity.
Similar studies are needed to confirm how green light may help those who suffer from non-migraine conditions beyond photophobia. However, if you are one of the many who suffer from migraine-like headache or light sensitivity, narrow-band green light can help soothe those symptoms without any side effects. A portable, affordable solution such as the Allay Lamp puts the power of narrow-band green light in the palm of your hands, offering a source of relief when it’s needed most.
The future gets brighter everyday.
We still have much to learn about the treatment of autoimmunity, Lyme, and the novel COVID-19 virus. However, thanks to increasingly sophisticated research, important solutions such as narrow-band green light therapy are becoming available directly to those who need them. Today, there is relief from photophobia at long last. Tomorrow, we’ll learn what new discoveries and new science will bring.