Photosensitivity, UV Light, and Lupus

brett — Tue, 11 Jul 2017 08:15:51 +0000

Having lupus means protecting yourself from dangers. But, photosensitivity presents a unique challenge and is often misunderstood.

You’ve read it before: People with lupus should limit their sun exposure. A study by Vila, L., et. al. published over 20 years ago, in 1999, reported that 98.3% of people with lupus understood that sunlight effects lupus disease activity. However, reports on photosensitivity, when covered by health outlets like WebMD and Healthline, have a tendency to oversimplify how the body reacts to sunlight. And, it is this simplification that may cause you to under-protect yourself.

Before we can see how ultraviolet light impacts people with lupus, and what to do about it, we need to do a quick physics lesson. To help out, we got some insights from Dr. Emmanuel Dumont. Dr. Dumont received his PhD in biophysics from Columbia University before conducting research at the Jacobs Technion-Cornell Institute on UV light measurement. This expertise led him to develop Shade, a smartphone-connected and affordable UV sensor specifically designed for Lupus Warriors. Used by Olympian Shannon Boxx, Shade has transformed the way people with lupus approach sun exposure and UV light awareness.

Ultraviolet (UV) Light and Photosensitivity

Photosensitivity is how much an object (in health, we are typically looking at the skin) reacts when it is hit by photons. Understanding photons requires some knowledge of quantum mechanics — but essentially photons can be thought of as the physical particles/waves that make up light. The human eye can only see wavelengths within a certain range.

The colors of light that are visible are the portion of light that have a wavelength within the visible light spectrum which ranges from roughly 390 to 700 nanometers. Wavelengths outside of the visible spectrum, both with longer and shorter wavelengths, can have huge impact on people. UV light falls into this category as do x-rays and gamma rays. As Dr. Dumont shares, “UV is invisible and it is less than 5% of sunlight; yet it is responsible for 100% of sunlight’s impact on health.”

And, UV light doesn’t only come from the sun. The lightbulbs in your office, the fire in your fireplace, and a hot coal in a barbecue all emit UV light. This is because UV light is a form of electromagnetic radiation.

UV Light and Lupus

A study by Wysenbeek, A., et. al, 1989 found that 73% of people with systemic lupus erythematosus (SLE) reported being photosensitive. And, further study by Sanders, C.J.G., et. al, 2003 found that 93% of participants with lupus experienced an abnormal reaction to UV light.

These abnormal reactions can vary by person and vary by location on the body. Rashes and skin lesions are common reactions to UV light, including hives and the butterfly rash on the face. Additionally, there is some evidence that UV light exposure may increase other systemic flare factors, such as fatigue and weakness.

Strategies to avoid receiving too much UV light vary, but include wearing long sleeves and pants, even on the hottest days, and use of broad-spectrum sun screens. However, these approaches do not allow for accurate self-analysis or tracking of your personal UV light exposure. This is a big problem, and one that Dr. Dumont has focused on with the creation of Shade.

“Today, there is a large gap in terms of reliability and accuracy between affordable consumer devices and expensive scientific laboratory equipment,” said Dr. Dumont. “Shade’s technology bridges this gap.”

Development of Shade

Dr. Dumont teamed up with Dr. Shayak Banerjee, who is an expert on UV lithography, to bring the accuracy of the lab to everyday life. The pair created a proprietary technology that uses a silicon diode and advanced calibration to measure UV. This technology allows them to measure UV 25 times more accurately than other UV sensors which estimate UV based on brightness.

Following the development of the technology, Shade worked with IDEO, the global design and innovation firm, to create a stylish and elegant body for the sensor that looks as great as the science inside it. Moreover, it uses a clever and versatile magnetic clasp that fits all types of clothing while keeping the sensor securely in place.

Shade connects wirelessly to your smartphone (iPhone or Android). The app provides a dashboard of your current level of UV exposure for a given day and helps you understand how increased UV exposure impacts you personally. Everybody is different so Shade can help you establish daily limits so you don’t push beyond what works for your body.

Dr. Dumont adds: “Patients need to keep track of their cumulative UV exposure over the day, an arduous task given the high variations of UV exposure inside a car, in the shade, in direct sunlight.” It has never been easier or more accurate than with Shade.