Prevalence of cutaneous adverse effects of hairdressing: a systematic review.
OBJECTIVE
To identify studies of the prevalence of cutaneous complications of hairdressing in (1) hairdressers and the general population and (2) those more common in people of African ancestry.


METHODS
Three versions of MEDLINE were searched from January 1966 through December 2004 and with a repeated search in August 2005 using 2 groups of search terms: group 1, terms used for hair care and specific study designs: survey, cross-sectional study, and cohort study; group 2, the terms African hair, Afro-Caribbean hair, African American hair, central centrifugal cicatricial alopecia, acne keloidalis nuchae, traction alopecia, and synonyms for each.


METHODS
All identified cross-sectional and cohort studies of cutaneous adverse effects were included and their quality assessed using criteria developed by Radulescu et al.


RESULTS
Four studies used either questionnaires or patch testing to estimate the prevalence of cutaneous adverse effects of hair chemicals in the general population and found a prevalence of contact dermatitis, secondary to use of hair dye, of 5.3% and of allergy to paraphenylenediamine of 0.1% to 2.3%. Working as a hairdresser is associated with a prevalence of contact dermatitis ranging from 16.4% in larger cohort studies that included a clinical examination to 80% in the smaller, questionnaire-based studies. Three studies of people of African ancestry found a prevalence of acne keloidalis nuchae ranging from 1.3% to 13.7% and of traction alopecia of 1%. None of these were in the general population.


CONCLUSIONS
Working as a hairdresser is associated with an increased risk of contact allergy and/or hand dermatitis. Studies of skin disorders of individuals of African ancestry are needed to quantify the health burden and clarify causal variables of these disorders. It is not clear how much the unique shape of the African hair follicle contributes to the development of these conditions.
Khumalo
Nonhlanhla P
NP
Division of Dermatology and School of Public Health and Family Medicine, Groote Schuur Hospital and University of Cape Town, Cape Town, South Africa.
Jessop
Susan
S
Ehrlich
Rodney
R
D001505:Beauty Culture; D044383:Black People; D017449:Dermatitis, Allergic Contact / Q000453:epidemiology / Q000209:etiology; D009783:Dermatitis, Occupational / Q000453:epidemiology / Q000209:etiology; D006203:Hair Preparations / Q000009:adverse effects; D006229:Hand Dermatoses / Q000209:etiology; D006801:Humans; D001741:Black or African American
D006203:Hair Preparations