This month's news from across the specialty
What's hot
May 1, 2020
In this monthly column, members of Dermatology World's Editorial Advisory Workgroup identify exciting news from across the specialty.
Hair color is a result of melanin pigment produced by melanocytes at the base of the hair follicle. The pigment producing melanocytes differentiate from melanocyte stem cells found in the bulge area of the follicle. Depletion of these stem cells leads to "salt and pepper" hair color and eventually to gray hair. Stress has been associated with early graying (compare images of President Obama before and after his presidency, as one example), but biologic evidence supporting the link between stress and gray hair is lacking.
In the Jan. 22 issue of Nature, Zhang and colleagues reported a variety of stress models in mice to better understand the mechanisms by which stressful stimuli may induce early graying (Nature. 2020; 577: 676-81). They found that noradrenaline release by sympathetic nerves (which incidentally terminate near the bulge of the follicle) led to graying by non-reversible depletion of melanocyte stem cells. Conversely, blocking sympathetic activity prevented stress-induced graying in mice.
The evolutionary advantage of graying in humans in response to the sympathetic "fight or flight" response is unclear. In an accompanying editorial, Clark and Deppmann suggest that an animal that has earned grey hair through sufficient stress may lead to a higher place in the social order normally occupied by older animals (e.g., silverback gorilla) (Nature. 2020; 577(7792):623-624). Anecdotally, several reports in the literature describe unilateral "lack of graying" in humans on the side of the body that has undergone sympathectomy (Arch Dermatol. 1982; 118(11): 876-7).
The moral of this story is: don’t panic about gray hair — it may only make matters worse.
Climate change is causing a significant impact on our environment and health. Dermatologists should be aware of the ways climate change affects the skin, patients, and our well-being (JAMA Dermatol. 2019; 155(4): 415-416). Particulate matter smaller than 2.5μm (PM 2.5) has the ability to penetrate the body, carrying in pathogens and toxins. A recent research letter in the JAAD (https://doi.org/10.1016/j.jaad.2019.04.069) showed an increase in queries related to itch when there was an increase in fine atmospheric particulate matter. These findings may be explained by the fact that pollutants can activate cutaneous nerve endings mediated through release of neurotrophin and cause epidermal keratinocytes to release proinflammatory cytokines, which play a central role in itch. Furthermore, in animal models of atopic dermatitis, the binding of particulate matter to the aryl hydrocarbon receptor induces itch. This is supported by a growing body of evidence linking flares of atopic dermatitis to fossil fuel emissions and wildfires. Pollutants also lead to oxidative damage in the skin, this combined with higher temperatures, can lead to increased skin aging and risk of skin cancer. These environmental triggers are important to recognize for our patients. As individuals, and as a specialty, we should make efforts toward reducing carbon emissions, decreasing waste, and helping raise awareness to halt the effects of climate change.
How do patients perceive the use of artificial intelligence (AI) for skin cancer screening? The answer may not be clear. In a recent study in JAMA Dermatology, 69% of patents perceived that the greatest benefit of AI is allowing a more accurate diagnosis, and 85% perceived less accurate diagnosis to be the greatest weakness of AI (doi:10.1001/jamadermatol.2019.5014). How did they explain this contradiction? Patients recognize that AI could draw on more data than humans and evolve rapidly. At the same time, they were also concerned that a lack of context that could be gleaned from a physician-patient relationship or a limited training set would be problematic. Patients were excited about increased access with AI but were concerned about losing human communication. They placed a high value on AI assisting or augmenting a physician rather than replacing the physician. Patients are receptive to AI tools achieving the diagnosis but not as comfortable with the delivery of that diagnosis occurring without physician involvement. In an era of increasing efficiency and rapid diagnoses, human social interaction in the medical setting is still highly valued and desired.
On Dec. 18, 2018, HHS and the FDA issued a notice of proposed rulemaking (NPRM) and a draft guidance with the intent of lowering the cost and increasing access of certain prescription drugs by allowing for importation. The proposals detailed two pathways: (1) the importation from Canada by states, wholesalers, or pharmacists; and (2) manufacturers of FDA-approved drug products would be able to import the versions that they sell in foreign countries into the U.S.
The AADA Regulatory Policy Committee and Drug Pricing and Transparency Task Force discussed how these proposals would affect patient access. The AADA submitted comment letters on both proposed pathways. While the AADA is generally supportive of importation, the letters expressed concerns about the drug safety and patient cost. The AADA position statement on Patient Access to Affordable Treatments is in line with American Medical Association importation policies including requiring a closed distribution chain, and electronic track-and-trace technology to ensure the safety of drugs. The AADA asked the FDA, HHS, and CMS to ensure that patients realize the cost savings of importation should the proposals be finalized.
Dermatology has dealt with drug shortages and price spikes particularly for doxycycline, clobetasol, and lidocaine with epinephrine. Should any importation proposals be finalized, the AADA would educate member dermatologists about the process including benefits and risks for patients.
