- Allison Truong, MD, FAAD
- Comorbidities, Expert Insights, Treatment
Mark Lebwohl, MD
Icahn School of Medicine at Mount Sinai
New York, New York, United States
IPC Councilor
As Professor of Dermatology, Chairman Emeritus of the Kimberly and Eric J. Waldman Department of Dermatology, Dean for Clinical Therapeutics at the Icahn School of Medicine at Mount Sinai, past President of the American Academy of Dermatology (AAD), past Chairman of the Medical Board of the National Psoriasis Foundation (NPF), founding editor of the Journal of Psoriasis and Psoriatic Arthritis, Dr. Lebwohl is a prolific author, educator, researcher, and mentor, and considered a leading world expert on psoriasis.
In a recent interview, Dr. Lebwohl shares his expertise in caring for psoriasis patients as they age, along with some clinical pearls to consider and pitfalls to avoid in this patient population.
Older Patients May have a Higher Risk of Side Effects
Psoriasis patients of all ages may be prescribed many of the same treatments, including topicals, phototherapy, traditional oral agents (e.g., methotrexate, cyclosporine), new oral molecule inhibitors (e.g., apremilast, deucravacitinib) and biologic injectables. Approximately 15% of older psoriasis patients experience moderate to severe psoriasis, often requiring systemic treatments to maintain disease control.1 However, certain systemic agents that may be considered low risk in younger patients may have higher toxicities in older patients.
Methotrexate is a universally prescribed medication around the world for psoriasis. One of the rare side effects of methotrexate is bone marrow suppression. Studies show that the most frequent predisposing factors associated with bone marrow toxicity in methotrexate use are the concomitant use of non-steroidal anti-inflammatory drugs (NSAIDs), liver disease, immunosuppressants, underlying renal function impairment, low albumin, and dehydration.2 Many of these listed factors are commonly seen in older adults as a normal part of the aging process, thus putting this patient population at higher risk of side effects from methotrexate. “In fact, if you look at those who have died or developed pancytopenia from methotrexate, older patients are overrepresented,” says Dr. Lebwohl.
Dr. Lebwohl reminds prescribers that serum creatinine in older adults can be misleading. Serum creatine is a common marker used to assess renal function. Usually, lower levels suggest normal kidney function, whereas higher levels suggest poor kidney function. However, as creatine is a derivative of creatine phosphate, an energy source for skeletal muscles, serum creatinine levels are influenced by muscle mass. Thus, older patients with less muscle mass may have low creatinine levels, leading to overestimating their true renal function. According to Dr. Lebwohl, “an 81-year-old with a serum creatinine of 1.0 may only have a fraction of the kidney function of a 20-year-old with the same serum creatinine.” Thus, methotrexate dosing should be adjusted accordingly to reduce the risks of side effects.
Consider the Use of Comorbid Conditions as a Guide to Making Treatment Decisions
Dr. Lebwohl believes comorbid conditions should play a role in the provider’s decision on which systemic agent to start or not start in certain patients. For example, cyclosporine is not an ideal drug for someone with hypertension. Similarly, anti-TNF agents may not be a perfect treatment for someone with numerous skin cancers. In comparison, if someone has a history of a heart attack, an anti-TNF agent may help reduce the risk of subsequent heart attacks and overall mortality; if someone has psoriatic arthritis, anti-TNF or anti-IL17 agents have been shown to prevent further progression of radiographic joint damage.
Furthermore, many patients with concurrent chronic diseases are on other medications that need to be examined closely to prevent drug-drug interactions. Some patients may be taking medications that could exacerbate underlying psoriasis, such as NSAIDs, antimalarials, angiotensin-converting enzyme (ACE)-inhibitors, Inderal (and other beta blockers), interferons, lithium, and systemic steroids. A mnemonic that Dr. Lebwohl uses to remember these medications that exacerbate psoriasis is “NAILS.” Identifying these medications on a patient’s medication list and working with the prescribing providers to stop or switch to other agents may help patients improve their condition.
Older Patients with Extensive Disease can be Treated with Systemic Agents
Patients with moderate to severe psoriasis affecting more than 10% of body surface area continue to be challenging to treat with topical agents alone. Thus, phototherapy or systemic agents can be safely used in appropriately monitored older patients with psoriasis.
In the United States, insurance coverage for older adults is usually through Medicare or commercial insurance. If the medication is on the formulary, patients may have the cost fully waived or pay a portion of the cost, often referred to as a copay. Due to current government regulations, pharmaceutical companies may waive the copay costs for those with commercial insurance but not with Medicare. If a patient must pay a 20% copay of a medication, such as a biologic injectable, that may cost $100,000 USD a year, the cost may be prohibitive for this patient over time. Thus, for patients who require biologics, Dr. Lebwohl often uses agents that can be administered in the hospital or infusion center as these are usually covered through Medicare and include drugs such as intravenous (IV) infliximab, (IV) secukinumab, and tildrakizumab subcutaneous injection.
Given the availability of biologics and difficulties in transportation in older patients, phototherapy utilization has diminished dramatically over time. Yet, many centers continue to offer phototherapy as it continues to be an easy, safe, and effective treatment for widespread psoriasis.
In patients with concomitant psoriatic arthritis who have failed biologics, Dr. Lebwohl has utilized JAK-STAT inhibitors, such as tofacitinib (Xeljanz) and upadacitinib (Rinvoq), which are currently FDA-approved for psoriatic arthritis in the United States.
Treating Psoriasis in the Aging Population can be Challenging and Rewarding
Caring for older patients with psoriasis can be challenging, given the medical, financial, and social implications. As the world population ages, it is crucial to continue to include the aging patient population in clinical trials and research so that we continue to expand our understanding regarding the safety and efficacy of newer medications in older patients. Regardless of age, all patients with psoriasis deserve to live healthier, fuller lives for as long as possible.
References
- Treating Psoriasis in the Elderly: Biologics and Small Molecules. Megna M, Potestio L, Fabbrocini G, Camela E. Expert Opin Biol Ther. 2022 Dec;22(12):1503-1520.
- A Rare Case of Acute Methotrexate Toxicity Leading to Bone Marrow Suppression. Khuwaja S, Lyons M, Zulfiqar B. Case Rep Rheumatol. 2024 Mar 15;2024:7693602. doi: 10.1155/2024/7693602. PMID: 38523896; PMCID: PMC10959578.
