Psoriasis Podcast

When Should Phototherapy Be Used for Psoriasis?

Steven R. Feldman, MD, PhD; Joel M. Gelfand, MD


June 01, 2022

This transcript has been edited for clarity.

Steven R. Feldman, MD, PhD: Hi. Welcome to Medscape InDiscussion on psoriasis. I'm your host, Dr Steve Feldman. When psoriasis is extensive, it can have an enormous impact on patients' lives. We have many treatments now, including biologics. Before we had such revolutionary treatments, we relied on older drugs, like methotrexate and cyclosporine, and phototherapy. Does phototherapy still have a place in psoriasis treatment? It's far less costly than our biologics. To discuss the role of phototherapy in psoriasis, our guest today is among the most accomplished scientists in dermatology — perhaps the most accomplished scientist studying practical issues in dermatology. He's vice chair of clinical research and medical director of the Dermatology Clinical Studies Unit at the University of Pennsylvania, which is perhaps the leading center for clinical dermatology care and research in the United States. He's also a professor of dermatology and of epidemiology and biostatistics in epidemiology. Our guest also runs the UPenn Dermatology Phototherapy Treatment Center. I'm excited that we get to talk with Dr Joel Gelfand.

Joel M. Gelfand, MD: Thanks for having me and thank you for that kind introduction — and for triggering my rosacea; I think you have made me blush a little along the way.

Feldman: Joel, you've had such a remarkable career in dermatology, and you're not even old yet, like some of us. You're doing what's arguably the most important and cutting-edge research in our field. I don't know how I came across it, but I remember reading an article of yours on adherence to anticoagulants. What took you from there to where you are today?

Gelfand: That's a great question. I was working with a guy named Danny Singer, who's won a lot of teaching awards. He's an epidemiologist at Harvard and a physician as well. He was doing trials to prevent stroke, and adherence with [warfarin] was a really important issue. I got interested in that topic and got to work with him for a summer. That was one of my early publications as a medical student.

I thought I was going to have a career in general medicine, so I took an elective in dermatology, thinking I needed to know some dermatology. A guy named Dick Johnson, who was then at the Beth Israel Deaconess Medical Center — many people may know him; he wrote Fitzpatrick's Color Atlas and Synopsis of Clinical Dermatology. A lot of us learn the images of dermatology from his photographs. I couldn't help but fall in love with dermatology. My first day on the rotations impressed me — the variety of diseases we see and the incredible impact we can have on patients' well-being and their lives. At the time, HIV was a big issue. This was in the mid-1990s; I was really interested in HIV disease as well.

When I got interested in dermatology, there was a big controversy in those days about whether ultraviolet light would be safe for people with HIV. In those days and still today, we use it for eosinophilic pustular folliculitis, for prurigo nodularis, for psoriasis — a whole host of diseases that people with HIV are more prone to. But in those days, there was a sign from basic science models, from mouse models, that ultraviolet light could activate the promoter of the HIV virus. The worry was that if you treat people with ultraviolet light, you could rapidly progress their HIV disease, cause further immunosuppression, and have bad outcomes.

I took a year off from medical school to try to better understand my interest in dermatology and get some more experience in research. I met a guy named Mark Lebwohl, who was, at the time, the only person who said, "If you come up with a clinical idea . . . a clinical study you want to do . . . and you could design it, and figure out how to do it and fund it, go ahead and do it. In the meantime, you'll be in a lab, like most medical students were." Sure enough, I came across a woman named Mary Klotman, who was head of infectious disease at that time, and we designed a study where we followed a cohort of people with HIV disease getting phototherapy at Mount Sinai. We filed their HIV viral levels by PCR at repeated time points during the course of their treatment over several months and basically showed that their HIV viral levels didn't change at all. They were rock steady the entire time. That was one of my first main publications in the field of dermatology, back in the late '90s, and to this day, that's still the main paper we rely on for the safety of phototherapy in people with HIV disease. We still use phototherapy pretty commonly in that population.

Feldman: Medicine is such a small world. I remember Dr Klotman when I was a medical student at Duke; I think she was a medical resident.

Gelfand: That's exactly right. Yes, she's back at Duke as the dean now.

Feldman: I'm old enough to have started taking care of psoriasis patients before we had drugs that just quickly clear it up. We relied heavily on phototherapy. Today, what makes somebody a good candidate for phototherapy?

Gelfand: It's true. We've made a lot of advances in the field of dermatology — psoriasis in particular. It's such a pleasure to be able to help take care of these patients, because having people who struggle with their disease for so long and then — in some cases, within 2-4 weeks — they are completely clear is an amazing clinical experience with a patient and always incredibly gratifying for us as clinicians. None of our therapies are perfect. Patients often lose response to treatment over time.

Having the availability of phototherapy to help bridge patients when they're not potentially doing well on a biologic or for a substantial number of patients who are just concerned about using systemic agents for a disease is so important. Many people are looking for what they consider to be a natural alternative way to manage their psoriasis. This is obviously something that's very patient-centered, very popular with patients, because they feel they could do something to manage their disease without having to use pharmaceutical interventions. It's remarkable; the efficacy of phototherapy is quite high when it comes down to it.

We did one clinical trial where we compared phototherapy to adalimumab — one of our TNF inhibitors — to look at its cardiovascular effects. Interestingly, the first thing we saw was that phototherapy had some important benefits in the cardiovascular realm. It lowered C-reactive protein and lowered IL-6, which are both important inflammatory biomarkers for cardiovascular disease; it did that compared with placebo. It also improved HDL-p [high-density lipoprotein particle size] — the so-called good cholesterol. Of all the drugs we've studied, only phototherapy had that benefit. It's interesting, but there's not a ton of research out there about what ultraviolet light does to the cardiovascular system. The little bit that's been done generally suggests that it has a favorable outcome, and I think there's more work that needs to be done there. But coming back to efficacy, what really surprised us — this wasn't the point of study, it was just a secondary thing that we looked at — was that the PASI-75s [≥ 75% reduction in Psoriasis Area and Severity Index scores] was the same with phototherapy compared with adalimumab, and this was a trial targeting people who wanted to be on biologics. Ultimately, they all received open-label adalimumab.

A lot of them had bad scalp disease, bad nail disease, or genital disease — not the kind of people you may treat with phototherapy. The other thing is the PROs, the patient-reported outcomes. Both groups did very well on the patient-reported outcomes, but in general, the phototherapy people tended to do better than the adalimumab people, including on the EQ-5D [European Quality of Life (EuroQoL) 5 Dimensions] — a measure of overall health and wellness — particularly when it came to pain. People receiving ultraviolet light had a statistically significant improvement in their overall feeling of pain compared with placebo, and that was better than what was seen in people receiving adalimumab. This is a kind of striking finding, and I think it comes back to some of your own work, Steve, from years ago, which demonstrates that phototherapy does have some salutary effects on people. People feel well on it; it increases endorphins.

The other thing we can't disentangle, of course, is the impact of our staff. What does it mean to a patient with a chronic, stigmatizing, isolating disease to come to a place on a regular basis and interact with people who understand what's going on . . . who are empathetic and supportive of them? That may also have a major benefit on what's going on, from what we observed.

As a treatment, phototherapy still has a lot to offer for patients. In my own practice, I'm pretty practical with people. I basically lay out what their options are. I say, "We're lucky we have a lot of good choices for you; let's discuss what your options are." Generally, I'm going to try to avoid letting a patient choose something that's definitely not in their best interest. So, maybe someone who had a lot of skin cancer in the past, who has some signs of psoriatic arthritis and a lot of nail disease or scalp disease or genital disease . . . I'm going to try to shift them away from trying phototherapy. But these modalities are still very valuable in our armamentarium.

Feldman: I get the sense that the dogma is if you have a patient with psoriasis and arthritis, the phototherapy can help the skin but it won't help the joints. I hear you saying that phototherapy lowers CRP. It's lowering systemic levels of cytokines. Might phototherapy improve the psoriatic arthritis, too?

Gelfand: We don't know. Certainly, at this stage, we consider it not to be our main understanding of the effects of phototherapy. It could be studied in people with psoriatic arthritis. Occasionally, patients with psoriatic arthritis are doing well on their biologics or their other DMARDs [disease-modifying antirheumatic drugs] that the rheumatologist has them on, and phototherapy is a good option if they're not doing that well [with psoriasis lesions]. They've finally gotten their joints under control, but they may still have residual skin disease. An ultraviolet light may be something that could be beneficial to help them get full control of their disease without having to worry about changing their regimen and losing response in their joints. It's another situation in which one might want to consider phototherapy.

The other thing is people who are extremely medically complex. I just saw a patient the other day who has lupus. She's on a whole host of immunosuppressants. She has some localized, stubborn lesions of psoriasis. I offered her external laser; focal use of UVB is not going to trigger her lupus. I'm not giving it to her entire body, and she did not want to go on biologics and add additional immunosuppression to the already immunosuppressive medicine she's on. These are modalities that can be used by those of us who treat complicated patients — or even not necessarily complicated patients — to center around what the patient's preferences are. It's something that is important to have in our armamentarium to offer people.

Feldman: What are the various options for phototherapy? What kinds of phototherapy do we have, and how do we decide which to use?

Gelfand: We certainly have a variety of modalities in my program. We offer narrowband phototherapy for the total body — a unit that surrounds the patient. We have hand-foot phototherapy, for which we use, in our office, mainly UVA, and we've added psoralen to that.

We treat a lot of patients with difficult palmoplantar pustulosis. As much progress as we've made with biologics, it's sort of trial and error trying to help people with palmoplantar pustulosis, but they do pretty well with topical PUVA [psoralen ultraviolet A]. That's an option we frequently use for those patients.

There's excimer laser — concentrated UV light to the individual lesions — which can be very helpful. Sometimes patients get really long remissions, particularly with excimer laser treatment. Another reason why I use phototherapy in some patients is that for people who are worried about being on long-term therapy or feel like they don't want to take a treatment for the rest of their life, you could try phototherapy. Occasionally, I have people who have a home run: They go into remission and they're fine for a couple of years. Now, that's not the typical experience, but it does happen; and that's another reason to give these things a try.

The other option, and really the biggest challenge to administering phototherapy, is being able to get people into the office. So, home phototherapy is certainly an option. There are multiple vendors who make these devices. They come in different shapes and sizes — for example, things that are 4 feet high and just treat part of the body. I personally don't like to use those; they seem to be difficult to use. I tend to use something that's sort of like the size of a door — an exam room door — so they can treat one entire side of the body, and then they could turn around and get a dose on the other side of the body.

The last thing I would add is that Penn is one of the few centers that still uses the Goeckerman regimen — day care, we call it. Patients will come in and spend a couple of hours in tar. They'll get a little dose of UV light. They'll get maybe some anthralin cream. That's a therapy that can be helpful for people who are running out of biologic options, who may have unusual contraindications to biologics or other reasons that they can't go on them. It's a remarkably effective therapy. You have people come in who have this very severe psoriasis — their PASI is in the 30s or 40s — and in 3 days, they can be close to clear. Almost nothing works as fast as good old Goeckerman. It's just that these days, logistically, it's so hard to do, and it's rather unpleasant for a lot of patients. It's certainly not very popular now.

Feldman: My enthusiasm for offering patient tar as a treatment increased after many years of disuse, when we learned that aryl hydrocarbon receptors were mediating how it worked.

Gelfand: Yes, it's fascinating. We know that patients using tar tend to get remissions, so it will be interesting to see, with the new topicals targeting that mechanism, whether they're more likely to get remittive effects from it, whether they have more remittive effects with phototherapy. We have a lot to learn with these new [mechanisms of action] coming to use with topicals and psoriasis, which is exciting.

Feldman: I don't think you mentioned sun exposure. Do you consider that a form of phototherapy?

Gelfand: I certainly do. For many of my patients, the strategy may be all right. We're going to treat you intermittently. My patients who really just don't want to be on pharmaceutical medications — they may be on biologics over the winter, when things are bad — but then when the sun's coming out, they can often keep themselves in remission with natural sunlight. I usually tell people that they should go out as close to noon as possible, because that's when you have the most UVB coming out of the sun, in terms of what's going to hit the skin. You try to give it an estimate based on their skin type. Very fair-skinned people may want to start with 5-10 minutes maximum. If they're very dark-skinned, they might be able to do half an hour to an hour without much concern. I often tell them to put a little baby oil on the psoriasis itself, because you want to improve the optical properties of the skin, so the UV can penetrate better. Most patients will know this. They tell you, "In the summer, Doc, it clears up." So, it's certainly useful for the appropriate patient. Of course, I usually try to encourage people by saying, "We know what areas are not involved, like your face; cover that area up. You don't want to accumulate too much photo damage or sun damage. It's going to be a problem for you in the longer term."

Feldman: Dermatologists tend not to like tanning beds. I believe tanning beds are the most widely used form of phototherapy by people who have psoriasis. Is that something you ever encourage a patient to do?

Gelfand: That's a great question, Steve. I think it'd be a great thing to test because I think you're probably right. I'm involved in a number of social media platforms, including one called KOPA. Patients talk about tanning beds a lot and find them helpful.

It's ironic, for me as a person who's an academician, who tries to do things by the book and tries to follow the science. We think that tanning beds these days are mainly UVA, right? They don't have that much UVB in them; it's the goal of tanning beds to tan people, not burn them. Of course, UVA gives you immediate pigment darkening, so that's really gratifying for someone using a tanning bed. They come out of the tanning bed, and a few hours later their skin looks a little bit tan. It's that UVA effect, right?

In theory, it shouldn't be that beneficial, but patients tell us all the time that they find it helpful. I generally don't recommend it. But if my patients want to do it and they think it's helpful for them, I don't say no; I just explain what the potential issues are.

Feldman: I practice in a relatively rural area. People are very spread out. It's cumbersome for people to drive the distance they have to drive to come for phototherapy in my office. In contrast, you work in a high-density area where people are much closer; on the other hand, the traffic is much worse, too. I know a dermatologist who's got a light box in his office. He has psoriasis. He has a home light unit. He does his own light therapy at home. What are some of the advantages and disadvantages of home light?

Gelfand: This is a great part of the discussion. As physicians, we often forget how much we're asking people to do, whether it be complicated topical regimens we're asking them to use or other treatments. One of my patients wanted to do phototherapy for years, and he would do well — not usually clear; it would come back. I was trying to convince him that he should go on a biologic instead, because at this stage, he just wasn't having as good a response as he could have. But he was uncomfortable with that approach. I calculated the number of hours he had spent coming to and from phototherapy, even though we're a high-population-density area. Someone may be walking from only four or five blocks away, but that's still at least anywhere from a half hour to an hour out of your life by the time you get from point A to point B. The treatment is just a few minutes — very quick — but with the time to go from point A to point B, it could set people back.

Certainly, when you survey patients, treatment at home is highly popular; it's highly preferred for many reasons. Home phototherapy also avoids a lot of the discomfort patients may feel about disrobing in a public place; they have privacy and the doors are closed. It just often feels uncomfortable to people; they'd rather do it in their own home.

We're doing the LITE study right now — the Light Treatment Effectiveness study — which you're a part of. When I offer this study to patients, in which we explain, "It's just routine care and if you're willing to do phototherapy at home, we'll flip a coin and send you a machine if it comes up one way, or you just do phototherapy in the office a great deal if it comes up the other way." Their eyes often get really big and excited because of the power of being able to decide when you're getting your treatment done and not focusing your whole day on needing to get to the doctor's office by 2:00 on Monday — to know, if I can't do it at 6:00 PM, then I'll do it at 7:00 PM. I'll get to it when I can fit it into my day, or during a weekend or if traveling or things of that nature. Home phototherapy gives patients an enormous sense of control over their own disease management. It's really empowering for them. To me, it's one of the gratifying parts of research, to see how happy patients are when they're doing well with home phototherapy, because then they feel that they have more control of their disease.

Feldman: When patients are on home phototherapy, can you manage them using teledermatology services?

Gelfand: With the pandemic, if there was ever a silver lining, it's been the rapid adaptation of teledermatology. In March 2020, I was doing approximately 0% teledermatology, and then in April 2020, I was doing 100%. I do manage a lot of patients with teledermatology on phototherapy. I do the counseling, the initial assessment, determining whether they're appropriate. Certainly, we do want to see these people in person at least once a year, to do a thorough skin examination, a skin check. Telemedicine is very helpful for counseling, for managing well-controlled chronic conditions, maybe for looking at a couple of things. But for doing a good, detailed skin check, teledermatology is more challenging.

Feldman: While I've got you here, you're the leading epidemiologist I know of in the world of dermatology. You mentioned that phototherapy seemed like it was having a positive benefit from cardiovascular markers. Do you think it's possible that the net effect of dermatologists telling people to stay out of the sun, which has its benefits of reducing skin cancer risk, is overall having a negative effect on mortality? Because if you're having even a small positive effect with sun exposure on cardiovascular risk, it potentially could swamp all the mortality benefits of skin cancer reduction.

Gelfand: That's right. For example, thinking about psoriasis as a model: The excess risk of a person with psoriasis experiencing a cardiovascular event that we think is above and beyond a traditional cardiovascular risk factor far outweighs their risk of ever having melanoma by logarithms. I don't think we know the answer to it. There are some studies showing that epidemiologically, people who get more sun exposure tend to have lower rates of cardiovascular disease.

It's really hard to tease out cause and effect, because getting sun exposure may be related to other behaviors that allow you to be in good health, regardless of whether you have the economic wherewithal, for example, to do these things. There are some experimental studies in the dermatology literature showing that ultraviolet light lowers blood pressure through increasing nitric oxide; there is a mechanistic component there. I think the reason why we haven't sorted this out is the reason that a lot of things in medicine don't get sorted out: You don't have the right brains coming together. The people who know about cardiovascular disease know nothing about photobiology, and the people who know a lot about photobiology don't know anything about cardiovascular disease. It's very hard to bring these two disciplines together — a ripe area for research, in my opinion.

Feldman: What's one thing you want to pass on to the listeners before we wrap up?

Gelfand: With all the progress we're making in the field of psoriasis and having more options available, the more options we have, the more options we're going to need. As more and more patients are coming in for treatment, that means more and more patients will do well but will lose response or will have preferences for different things. To really be able to completely manage this disease, you must have phototherapy available to your armamentarium. You want be able to offer both narrowband phototherapy, excimer laser, and topical PUVA, because invariably, you're going to have patients come in who will need those types of treatment options. It's a great way to help our patients.

Feldman: With the availability of home phototherapy, I think, in theory, even if you didn't have the office phototherapy as an option, physicians can be offering people ways of getting home phototherapy.

Gelfand: One of the goals of the LITE study of about 1050 people with psoriasis — we've already enrolled more than 600 individuals — [is to test the hypothesis] that home treatment will be just as effective as office treatment. The challenge patients and providers have is that it's very difficult to get insurance approval for a home phototherapy machine. Oftentimes, insurance companies are aligned by durable medical goods. So, you prescribe a machine that may cost $4000, and the insurance company will say, "Wait a second; I don't want this on my budget. Have the pharmaceutical side spend $80,000 a year for life for this patient — or whatever that biologic is going to cost — because that helps the bottom line of durable medical goods." Home phototherapy is actually covered by Medicare. Certainly, a lot of the systems, such as Kaiser Permanente and the ones in which the insurers are also delivering the care, often make phototherapy available to patients. Hopefully, the work we're doing now will improve that access as well.

Feldman: Joel, thank you so much for taking time out of your extraordinarily busy and productive schedule to talk to me today. For our listeners, be sure to look for our next episode, where Dr Bruce Strober will talk with me about oral agents for psoriasis. I'm Dr Steven Feldman, and this has been Medscape InDiscussion on psoriasis. See you soon.


Plaque Psoriasis Treatment & Management

Eosinophilic Pustular Folliculitis

Prurigo Nodularis

Ultraviolet Radiation

Effect of UV-B Phototherapy on Plasma HIV Type 1 RNA Viral Level: A Self-Controlled Prospective Study

Effect of Two Psoriasis Treatments on Vascular Inflammation and Novel Inflammatory Cardiovascular Biomarkers: A Randomized Placebo-Controlled Trial

Sunlight Has Cardiovascular Benefits Independently of Vitamin D

Palmoplantar Pustulosis

Topical PUVA

308nm Excimer Laser in Dermatology

The Goeckerman Regimen for the Treatment of Moderate to Severe Psoriasis

Light Treatment Effectiveness (LITE) Study

Teledermatology: Idea, Benefits and Risks of Modern Age – A Systematic Review Based on Melanoma

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