Who is the most commonly affected by alopecia areata ?
Research into the demographics of AA suggest that 0.05%-0.1% of the population will be affected with AA at any one time (Rook 1991, Gollinck 1990, Safavi 1992). On this basis, it can be estimated there are between 30 and 60 thousand sufferers in the UK, between 112 and 224 thousand in the USA and worldwide – between 2.25 and 4.5 million! Of course, these figures are only estimates based on regional studies, and cover all forms of AA from small patches of hair loss through to alopecia universalis. The actual expression of AA in a population probably varies from region to region. Information on how AA affects different groups of people is lacking but, as an example, it is believed that AA is slightly more common in Japanese people – particularly people of Japanese decent living in Hawaii (Arnold 1952). A recent study has put the average lifetime risk of experiencing AA at 1.7%, considerably higher than most previous estimates at around 1% (Safavi 1995). There are two schools of thought a
