Physiological Changes in Scalp, Facial and Body Hair after the Menopause

I. Ali; F. Wojnarowska

Disclosures

The British Journal of Dermatology. 2011;14(3):508-513. 

In This Article

Discussion

This is the first epidemiological study in more than 20 years relating to facial and body hair distribution in a normal female population. The three largest studies of normal hair distribution in northern European females were conducted by Beek in 1950,[6] Ferriman and Gallwey in 1961,[1] and Lunde and Grottum in 1984,[7] only one of which combined the assessment of scalp and body hair; none divided subjects by menopausal status.

This is also the first study to assess the frequency and pattern of these hair changes specifically in normal postmenopausal women. Furthermore we have attempted to look at how these changes may develop or progress by dividing these data into age-related intervals. In this study, the most common form of hair loss was diffuse generalized hair loss, reported by over a quarter of women (26%); their mean age was 64 years compared with women with no subjective hair loss whose mean age was 59 years, suggesting that the changes are an age-related phenomenon.

The generalized scalp hair loss experienced by a large proportion of women could be explained by a telogen effluvium stimulated by falling oestrogen levels in women not taking hormone replacement therapy,[8] and would be a phenomenon of early menopausal years. However, most women reporting diffuse generalized hair loss were in the late menopause (mean time postmenopause of 15 ± 10·6 years compared with 10 ± 9·2 years for those without hair loss) and this time scale would not support telogen effluvium induced by falling oestrogen as a cause.

An alternative explanation is that diffuse generalized hair loss is an age-related process. Birch et al.[9] found an age-related decline in hair density in women but no clinical correlation was assessed. Age-related hair loss has been referred to by some as 'senescent' hair loss,[10] and several authors have described the histopathological features of senescent balding in men but evidence for this condition in females is lacking.[11] There is little reference to this classification of hair loss in the current medical literature and no information on the frequency, age of onset or pathological features of this condition in women.

In this study 9% of women described frontal hair thinning. This was a smaller proportion than in previous objective studies. Hamilton [12] found 37% (16 of 43) of women over 50 years had vertex alopecia. Norwood[13] reported a frequency of 26% (113 of 438) for vertex alopecia. Birch et al.[9] also reported a greater frequency of FPHL with age, reporting 38% of females over 70 years to have FPHL. None of these studies analysed findings in relation to menopausal status or the effect of HRT. Venning and Dawber[14] were the first to do this and found an even greater proportion (63%) of postmenopausal females had diffuse scalp vertex alopecia. The difference may reflect subjective under- or misreporting, or the major change in FHPL may occur prior to the menopause.[3]

Frontal thinning significantly correlated with temporal hair loss, suggesting a common pathology and could be related to androgen action akin to patterned balding in men. This finding differs from those in a study by Birch and Messenger[15] who found no correlation between FPHL and temporal recession in a mixed cohort of pre- and postmenopausal females. The role of androgens in this pattern of hair loss is supported by the finding that this pattern correlated with increased facial hair (discussed in detail below).

This study found facial hair gain was reported by almost half the women surveyed. The frequency of facial hair gain varied with site. Hair gain on the chin was more common than on the upper lip. These findings are similar to the clinical findings reported by Ferriman and Gallwey[1] whose data showed a 2·2-fold increase in the upper lip hair score and a 20-fold increase in chin hair score when comparing women aged 15–24 years with those aged 65–74 years. These findings suggest that the chin is a special site where endocrine changes associated with the menopause or ageing have a greater effect on hair density than elsewhere on the face.

We found that the frequency of subjective facial hair gain did not change across age groups, suggesting that the stimulus for the development of facial hirsutism does not increase incrementally with age, but occurs early in the menopause and is not a cumulative process. This may have important implications for the timing of treatment as perhaps early treatment with androgen blockers such as spironolactone or 5-alpha reductase inhibitors such as finasteride or dutasteride could arrest or decrease the frequency of facial hair gain.

The concept of the menopause being a state of relative androgen excess due to the loss of ovarian oestrogen would give rise to the hypothesis that body hair would increase after the menopause. In contrast, Ferriman and Gallwey[1] found that body hair scores were lower in older women.

The results of this study have shown that subjective hair loss is significantly more common than hair gain. The frequency of hair loss increased incrementally with age. These findings confirm those of previous observational studies that have shown a decrease in body hair scores with increasing age in older women.[1,6]

The incremental decrease in body hair score with age suggests that this is not solely related to endocrine changes of the menopause. If this were the case, we would expect to observe a sharp decline in body hair score in the immediate period postmenopause followed by a plateau. We observed a decrease in body hair score decades beyond the average age of menopause, which suggests that ageing influences hair density independent of the endocrine changes relating to the menopause.

Some have alluded to an evolutionary process in which body hair as a symbol of sexual maturity is redundant after the reproductive years and therefore the ageing adult human loses body hair. Hair can be divided into two populations, sexual and nonsexual. Sexual and nonsexual hair growth are both influenced by a range of steroid hormones; however, androgens are the principle effectors for sexual hair.[2]

Sexual hair responds to androgen excess with facial and especially chin and upper lip hair. This androgen excess is also responsible for the FPHL that can develop on a background of nonsexual diffuse scalp hair loss. It is possible that other endocrine factors may influence body hair as levels of growth hormone and both adrenal and ovarian androgens decrease with age. The age-related decline of endocrine hormones such as testosterone can take effect over several decades and could explain the gradual age-related loss of body hair observed in this study. This study does demonstrate that body hair gain in postmenopausal women is uncommon and therefore should prompt further investigation.

This is the first study to correlate information on the pattern of scalp, facial and body hair in postmenopausal women. We have been able to demonstrate two distinct patterns of hair loss in the postmenopausal female with different possible mechanisms and implications for general health and treatment.

Firstly, we noted a pattern of diffuse generalized hair loss in which diffuse generalized scalp hair loss significantly correlates with body hair loss (P < 0·001) and increasing age (P < 0·001). The pattern of generalized scalp and body hair loss with age suggests a common aetiological factor that affects all hair as opposed to targeting androgen-sensitive sites. Theoretically this may be an age-related factor(s) that induces hair loss or the loss of function of a factor(s) that maintains hair density. There may be a combination of factors activated by the process of ageing and/or influenced by the loss of ovarian oestrogen and androgen as a result of the menopause. It is unclear if this pattern of hair loss represents a clinical sign of age-related endocrine failure (with adrenal androgen or growth hormone being potential candidates), as levels decrease incrementally with age and hair follicles bear receptors for both. In contrast body hair gain was rare, suggesting that this should be investigated further to ascertain a cause, particularly in older menopausal females.

Secondly, we noted that patterned scalp hair loss (frontal loss and temporal recession) was associated with increased facial hair (P < 0·05). These women had relatively higher body hair scores and were younger than women with diffuse hair loss (P < 0·05).

This suggests that this pattern is the female correlate of male-pattern balding. In men, dihydrotestosterone is a key factor in the stimulation of beard growth and the development of male-pattern balding.[16] The correlation between patterned forms of hair loss and facial hair gain in postmenopausal women suggests that a similar process may occur in females. This could have important implications for potential therapeutic options in the form of 5-alpha reductase inhibitors. Their role in the treatment of FPHL is controversial[17] and our findings suggest that females with facial hair gain in association with FPHL could benefit from this treatment.

This study does have limitations including the fact that as a subjective record of hair change, variation will exist between individuals and their perceptions of change. The ideal study would be a long-term cross-sectional observational study through the menopausal years to older age. The advantage of our study is that it relates changes to premenopausal hair density and therefore may be a more sensitive measure of change.

In conclusion, this study has highlighted two distinct patterns of hair change in the postmenopausal female. Generalized scalp and body hair loss significantly correlated with age. Patterned forms of scalp hair loss were associated with facial hair gain suggesting that androgens may play an aetiological role.

Considering the changes in body mass ratio and in the shape of women in the last four decades it is possible that both may impact on hair. These patterns of scalp, facial and body hair distribution provide initial insights into the aetiological factors involved in inducing these changes and may be relevant in identifying therapeutic agents to prevent and reverse unwanted hair changes. In addition, as hair changes reflect a multitude of endocrine influences further study in this area may help us understand how these changes may act as indicators of health or susceptibility to disease.

Comments

3090D553-9492-4563-8681-AD288FA52ACE
Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as:

processing....