Hairdressing and the prevalence of scalp disease in African adults.

BACKGROUND: Anecdotal reports suggest that certain scalp disorders are common in Africans and may be associated with hairstyles.
OBJECTIVES: This study of 874 African adults in Cape Town was performed to test this hypothesis.
METHODS: A questionnaire was administered and scalp examinations performed, after ethics approval.
RESULTS: Participants included 30.9% men and 69.1% women (median age 36.1 years, range 18-99). Most men had natural hair: 91.7% vs. 24.3% women. The majority of men had recent haircuts (< 4 weeks): 74.8% vs. 9.9% women. The overall prevalence of acne (folliculitis) keloidalis nuchae (AKN) was 3.5%: higher in men than women (10.5% vs. 0.3%). AKN prevalence was not associated with whether clippers or blades were used. However, it was associated with haircut symptoms. Haircut-associated symptoms, i.e. at least one episode of transient pimples (or crusts) and bleeding (however small) were reported in 37% and 18.9% of men, respectively. The latter may have implications for disease transmission. Most women (58.7%) had chemically treated hair (49.2% relaxed and 9.6% permed hair) vs. 2.3% men. The prevalences of traction alopecia (TA) and central centrifugal cicatricial alopecia (CCCA) were 22.6% and 1.9%: higher in women (31.7% vs. 2.2% and 2.7% vs. 0%, respectively). CCCA was highest in women > 50 years (6.7% vs. 1.2%). TA prevalence was highest if the usual hairstyle was extensions attached to relaxed hair (48%).
CONCLUSION: We found associations between specific scalp diseases, hairstyles, gender, and age. These associations need further study, better to elucidate determinants and to improve disease prevention and treatment.