The natural history of alopecia areata is unpredictable. Extreme variations in duration and extent of the disease occur from patient to patient. Alopecia areata most often is asymptomatic, but some patients (14%) experience a burning sensation or pruritus in the affected area. The condition usually is localized when it first appears. Of patients with alopecia areata, 80% have only a single patch, 12.5% have 2 patches, and 7.7% have multiple patches. No correlation exists between the number of patches at onset and subsequent severity. Alopecia areata most often affects the scalp (66.8-95%); however, it can affect any hair-bearing area.
The beard is affected in 28% of males (see image below), eyebrows in 3.8%, and extremities in 1.3% of patients (see second image below). More than one area can be affected at once.
Localized alopecia areata
Episodes of localized (<50% involvement) patchy alopecia areata usually are self-limited; spontaneous regrowth occurs in most patients within a few months, with or without treatment.
Extensive alopecia areata
Extensive (>50% involvement) forms of alopecia areata are less common. Alopecia totalis or alopecia universalis are reported to occur at some point in 7% of patients; alopecia areata involving more than 40% hair loss is seen in 11%. The proportion of patients with alopecia totalis appears to decrease with every decade of life.
In 30% of patients with alopecia totalis, complete hair loss occurred within 6 months after onset of disease. Sharma et al reported a mean progression period to alopecia totalis of 4 months after onset. The natural evolution of alopecia totalis is unpredictable, but recurrences of alopecia areata (not necessarily alopecia totalis) are expected.
In a study involving 736 patients, the relapse rate was 90% over 5 years. One percent of children and 10% of adults can experience long-lasting regrowth. Forty-four percent of children and 34% of adults experience a significant period of normal or near-normal hair growth. Twenty-two percent of children and 34% of adults do not experience regrowth.
- Sharma VK, Dawn G, Kumar B. Profile of alopecia areata in Northern India. Int J Dermatol. 1996 Jan. 35(1):22-7. [Abstract].
- Muller SA, Winkelmann RK. Alopecia areata. An evaluation of 736 patients. Arch Dermatol. 1963 Sep. 88:290-7. [Abstract].