Medicosnext
Hair loss is an increasing complaint in Dermatology OPD, and more so after the emergence of the COVID-19 pandemic. There is a huge rise in number of cases we see that comes with hair loss problems, and not to mention, the psychological impact it has on the patients. While we are aware of respiratory and cardiovascular complications during acute infection, little is talked about the post infection sequel. So, what is post-COVID hair loss, and how can we treat it?
For anyone who has been alarmed by hair loss, there is a good news. Hair loss after COVID infection is extremely common, and with time, the lost hair grows back to its normal state. Only thing we cannot do is to prevent it! But, one advise we can give is to stop worrying too much about it, since stress can negatively affect hair growth. Managing stress and eating a balanced diet is crucial to grow back healthy hair.
Before talking about how COVID infection causes hair loss, let’s take a look on the basics of hair growth cycle. Hair growth cycle consists of three phases: Anagen, Catagen, and Telogen.
• Anagen is the growth phase that lasts anywhere between 3-10 years. During this phase, rapid cell division occurs in the hair bulb and dermal papilla.
• Catagen is the transitional phase that lasts 2-3 weeks. During this phase, cell division stops and melanocytes stop producing pigment.
• Telogen is the resting phase that lasts 3-4 months, and during this phase, hairs shed from the scalp.
When body is in acute stress, which may be due to an illness like typhoid or dengue, or major surgery or pregnancy, the hair growth cycle is disturbed. Hair in anagen (growth) phase prematurely enters into telogen (shedding) phase. This causes increase in hair shedding, or hair loss. However, losing 100 hair strands per day is considered normal and shouldn’t raise any worries.
In the case of COVID-19 infection, hair loss is not seen in acute disease, but rather, a few months post infection. Patients typically notice increase in hair shedding two-three months after the disease itself. It is diagnosed as telogen effluvium (TE); it lasts for six months in the absence of any other underlying factors. New hair growth begins and it can take 9-12 months for the hair to grow back to its previous form.
Hypothesis like action of pro-inflammatory cytokines and direct viral damage on the hair follicle have been postulated as its pathogenesis. Consistent increase in pro- inflammatory cytokines like interferon type 1 and 2, TNF alpha, IL 1b and 6 have been seen in COVID-19 infection, and association with infection-related skin manifestations like urticaria, vasculopathy, morbilliform rashes, and COVID toes has been established. This cytokine-storm also causes direct damage to hair producing matrix cells, causing excessive hair shedding.
Clinically, patients come with a history of diffuse hair loss and complain of seeing clumps of hair in the shower, pillow, or comb. Some tests are performed to confirm the diagnosis of Telogen Effluvium. Hair pull test is strongly positive in these cases—50-60 strands of hair are gently pulled, if more than 10% of hairs are pulled away from the scalp, the test is regarded as positive. Trichospcopy shows the reduction in hair density.
Telogen effluvium is one of the most common causes of hair loss, particularly in women. Many triggers have been identified, such as stress, drugs, major surgery, pregnancy, crash diet, nutritional deficiencies, febrile illness like typhoid, dengue, TB, etc. Looking back at history, in 1919, the influenza epidemic caused acute TE two weeks – three months after the onset of fever. Comparably, people suffering from COVID-19 infection have similar pattern and timing of hair loss post infection. Moreover, stress related to the COVID pandemic and hair fall together have also imposed on further hair loss.
Studies have reported incidence of TE after severe COVID-19 infection, but in my practice, TE is seen with mild to moderate disease, as well. As discussed, TE cannot be prevented, but one can focus on healthy life choices. Random use of vitamin supplements is also not encouraged. In suspected case, blood tests are performed, and supplements can be given, if deficient. Consuming balanced diet, including green leafy vegetables, and fruits, lean meat and fish, egg, lentils, seeds, etc. can improve the nutritional state and help in better growth of hair. Six – eight hours of sleep, 30 minutes of exercise each day, enough hydration, and managing stress are some major life choices that can aid in healthy hair growth. In the clinic, platelet rich plasma (PRP) therapy can be done to promote hair growth.
While hair loss is a distressing process, hair loss post COVID has a good outcome if one focuses on healthy lifestyle. One shouldn’t panic, but visiting a dermatologist on time is still necessary to make a correct diagnosis, which can aid in further management. Clinicians should be aware of delayed-onset TE post-COVID as a common entity, and should be able to manage it efficiently.
