Brian Keith Fisher

Hair Growth Parameters in Pre- and Postmenopausal Women

Women who undergo menopause have a cessation of ovarian estrogen production. This dramatic hormonal alteration is known to have significant effects on the skin and cutaneous appendages. As our understanding of the molecular and hormonal controls on the folliculo-sebaceous unit has grown, there has been renewed interest in the role of estrogens in modulating hair growth. Specifically, the relatively recent discovery of estrogen receptor beta has broadened and redefined prior concepts of estrogen activity and signaling. In a cohort of pre- and postmenopausal women without alopecia, a modified phototrichogram was used to measure hair density, growth rate, and percentage anagen. Optical fiber diameter analysis (OFDA) was used to determine hair diameters. Our aim was to determine whether there are any changes in hair characteristics and hair growth parameters that correlate with menopausal status. Postmenopausal women had significant changes, mainly in the frontal scalp as compared to premenopausal women. These changes included lower frontal scalp percent anagen hairs, growth rates, and hair diameters. Further study of hair changes in response to menopause provides an important opportunity for identification of treatments, targets, and strategies that may significantly benefit women.

Hair care practices and structural evaluation of scalp and hair shaft parameters in African American and Caucasian women

How African American hair fragility relates to hair care practices and biologic differences between races is not well understood. To assess the differences between perceptions of hair health, hair care practices, and several biologic hair parameters between Caucasian and African American women. A questionnaire on perceptions of hair health and hair care practices was administered. Biological and structural parameters of hair shaft and scalp, including growth, density, diameter, cycle, breakage, and scalp blood flow were also assessed in this case–control study. Significant differences between the Caucasian and African American women were observed in the questionnaire and biologic study data. Regarding self‐reported perceptions of hair health, there were differences in the following: hair shaft type (P < 0.001), hair breakage (P = 0.040), and desire to change hair (P = 0.001). Regarding self‐reported hair care practices, there were differences in the following: location of haircutting (P = 0.002) and washing (P = 0.010), washing frequency (P < 0.001), chemical relaxer use (P < 0.001), hooded hair dryer use (P < 0.001), and hair shaft conditioner use (P = 0.005). The two groups had similar practices in regard to the use of hair color, frequency of hair color use, chemical curling agents, and handheld blow dryer use. Regarding biological and structural parameters, there were differences in the following: hair growth rate (P < 0.001), density (P = 0.0016), diameter (P = 0.01), number of broken hairs (P < 0.001), and blood flow (P = 0.03). There was no significant difference in hair cycle parameters.The differences in hair care practices and hair fiber morphology among African American women may contribute to clinically observed variation in hair fragility and growth.