As the days shorten in the Northern Hemisphere, the prevalence of influenza and the common cold increase. There are some interesting relationships between these winter illnesses and chronic dermatological conditions. This is a relatively broad topic that touches on both common causation and issues of vaccination recommendations.
It has been known for some 40 years that physiological and psychological stress tends to increase susceptibility to rhinoviruses and other viral upper respiratory illnesses. (1) Likewise, we have more recently seen evidence that chronic dermatological conditions are aggravated by stress as well. (2) On a practical level, a number of stress responses are likely involved in both, such as chronic desensitization of cortisol receptors and a shift towards TH2 adaptive immune response. Those would both lead to an increased susceptibility to new viral and bacterial infections as well as increased autoimmune disease and allergy activity.
Of course, some of these can be vicious cycles of increased stress, whether from a viral cold which increases the overall chronic stress response, which then increases psoriatic disease activity, or the converse, where psychological stress over a skin condition causes increased susceptibility to the common cold. (2)
From a patient counseling point of view, it is worth mentioning these relationships to patients. Practicing good handwashing will help them avoid colds and influenza, but can worsen their skin condition. Also, trying to manage stress is good for both dermatologic and general health reasons.
Considering the many immunomodulatory and immunosuppressant treatments used in dermatological practice, the question of how to vaccinate patients is common. As mentioned above, we know that a bad bout of influenza is likely to exacerbate many dermatoses by increasing overall stress response. Also, the course of common winter illnesses in the immunosuppressed is likely to be more severe with increased morbidity and mortality.
A recently published international review of 15 vaccination guidelines concluded that inactivated pneumococcal and injectable influenza are the two essential vaccines recommended in all immunocompromised patients. (3) Although there have been isolated case reports of increased psoriasis activities following influenza vaccination, they are extremely rare. In a French study of the 2009-10 influenza vaccine, only 10 cases of increased psoriasis activities were reported by 6 dermatologists (out of approximately 3000 dermatologists and 2 million psoriasis patients). Of note in the same French study, only about 20% of psoriasis patients were vaccinated, which is far less than is ideal. (4)
In conclusion, appropriate patient counseling on links between dermatological disease and common winter illnesses, including vaccination recommendations is an important topic as winter approaches.
