Chemical relaxers historically have been associated with CCCA but have not been definitively implicated as causative.2,3,4,13 Most studies have not demonstrated a statistically significant association between chemical relaxers and CCCA because, with a few exceptions,13 studies have either been based on surveys or have not employed trichoscopy or scalp biopsy. In one of those studies, patients with CCCA were determined to be 12.37 times more likely to have used a chemical relaxer in the past (P<.001).13 In another study of 39 women in Nigeria, those who had frequent and prolonged use of a chemical relaxer developed scarring alopecia more often than those who did not use a chemical relaxer (P<.0001). However, it is now known that the pathogenesis of CCCA may be related to an upregulation in genes implicated in fibroproliferative disorders (FPDs), a group of conditions characterized by aberrant wound healing, low-grade inflammation and irritation, and excessive fibrosis.14 They include systemic sclerosis, keloids, atherosclerosis, and uterine fibroids. The risk for certain FPDs is increased in individuals of African descent, and this increased risk is thought to be secondary to the protective effect that profibrotic alleles offer against helminths found in sub-Saharan Africa. A study of 5 patients with biopsy-proven CCCA found that there was increased expression of platelet-derived growth factor gene, PDGF; collagen I gene, COL I; collagen III gene, COL III; matrix metallopeptidase 1 gene, MMP1; matrix metallopeptidase 2 gene, MMP2; matrix metallopeptidase 7 gene, MMP7; and matrix metallopeptidase 9 gene, MMP9, in an affected scalp compared with an unaffected scalp.14 Still, chemical relaxers weaken the hair shaft and follicle structure, increasing the possibility of hair breakage and allowing for inflammation and trauma to render negative follicular effects.3,13
The following interventions can be recommended to patients who thermally or chemically treat their hair to prevent hair damage:
- Decrease the frequency of thermal straightening.
- Use lower heat settings on flat irons and blow-dryers.
- Thermally straighten only clean dry hair.
- Regularly trim split ends.
- Use moisturizing shampoos and conditioners.
- Have a trained professional apply a chemical relaxer, if affordable.
- Consider decreasing (1) the frequency of chemical relaxer touch-up (to every 8 to 10 weeks) and (2) the overall manipulation of hair. There is a fine balance between not treating often enough and treating too often: The transition point between chemically processed hair and grown-out roots is a high-tension breakage point.
- Apply a thick protective emollient (known as scalp basing) to the scalp before applying a relaxer1,5; this protects the scalp from irritation.
Techniques for Braids, Weaves, and Twists
Braids and cornrows, sewn-in or glued-on extensions and weaves, and twists are popular hairstyles. When applied improperly, however, they also can lead to alopecia.1-5,11,12 When braids are too tight, the patient might complain of headache. Characteristic tenting—hair pulled so tight that the scalp is raised—might be observed.3,5 Twists are achieved by interlocking 2 pieces of hair, which are held together by styling gel.1,4 When twists remain over many months, hair eventually knots or tangles into a permanent locking pattern (also known as dreadlocks, dreads, or locs).1,2,4 In some cases, the persistent weight of dreadlocks results in hair breakage.1,3,5
The following recommendations can be made to patients who style their hair with braids or cornrows, extensions or weaves, twists, or dreadlocks:
- Apply these styles with as little traction as possible.
- Change the direction in which braids and cornrows are styled frequently to avoid constant tension over the same areas.
- Opt for larger-diameter braids and twists.
- Leave these styles in place no longer than 2 or 3 months; consider removing extensions and weaves every 3 or 4 weeks.
- Remove extensions and weaves if they cause pain or irritation.
- Avoid the use of glue; opt for loosely sewn-in extensions and weaves.
- Consider the alternative of crochet braiding; this is a protective way to apply extensions to hair and can be worn straight, curly, braided, or twisted.5,12
Techniques for Other Hairstyling Practices
Low-hanging ponytails or buns, wigs, and natural hairstyles generally are considered safe when applied correctly.1,5 The following recommendations can be made to patients who have a low-hanging ponytail, bun, wig, or other natural hairstyle:
- Before a wig is applied, hold the hair against the scalp with a cotton, nylon, or satin wig cap and with clips, tapes, or bonds. Because satin does not cause constant friction or absorb moisture, it is the safest material for a wig cap.5
- Achieve a natural hairstyle by cutting off chemically processed hair and allowing hair to grow out.5
- Hair that has not been thermally or chemically processed better withstands the stresses of traction, pulling, and brushing.5
- For women with natural hair, wash hair at least every 2 weeks and moisturize frequently.5,12
- Caution patients that adding synthetic or human hair (ie, extensions, weaves) to any hairstyle to increase volume or length using glue or sewing techniques1-4,11 can cause problems. The extra weight and tension of extensions and weaves can lead to alopecia. Glue can trigger an irritant or allergic reaction, especially in women who have a latex allergy.1,4,5,11
Practice Implications
Women of African descent might be more susceptible to alopecia because of the distinctive structural properties of their hair and the various hair treatments and styles they often employ. Physicians should be knowledgeable when counseling these patients on their hair care practices. It also is important to understand that it might not be feasible for a patient to completely discontinue a hair treatment or style. In that situation, be prepared to make recommendations for safer hairstyling practices.