What are the possible causes of hair loss in a 78-year-old woman?

Hair Loss in a 78-Year-Old Woman

In a 78-year-old woman, hair loss is most commonly due to female pattern hair loss (FPHL), which presents as diffuse thinning over the central scalp with preservation of the frontal hairline, though age-related physiological changes, nutritional deficiencies, thyroid dysfunction, and scarring alopecias like frontal fibrosing alopecia must also be considered. 1, 2, 3

Primary Causes by Pattern

Female Pattern Hair Loss (FPHL)

• Most common cause in elderly women, affecting up to 37% of women over 65 years 2
• Two typical patterns: centrifugal expansion in mid-scalp or frontal accentuation ("Christmas tree" pattern) 1
• Critical distinction: Isolated FPHL with normal androgen levels should NOT be considered a sign of hyperandrogenism 1
• Worsens after menopause due to relative androgen excess and loss of estrogen's protective effects on hair follicles 4, 3

Age-Related Physiological Changes

• Postmenopausal women experience diffuse generalized scalp hair loss (26% report this pattern) 5
• Important caveat: True "senescent alopecia" as a primary diagnosis is rare—most elderly hair loss is androgen-driven rather than purely age-related 6
• Hormonal changes during menopause lead to decreased hair density, decreased caliber, and altered texture due to estrogen-sensitive follicular changes 4

Scarring Alopecias (Higher Risk in Elderly)

• Frontal fibrosing alopecia: Predominantly affects postmenopausal women, causes progressive scarring hair loss at frontal hairline 2, 3
• Erosive pustular dermatosis of the scalp: Mainly affects elderly women, leads to scarring alopecia 3
• Central centrifugal cicatricial alopecia and fibrosing alopecia in pattern distribution 1

Telogen Effluvium

• Chronic telogen effluvium frequently superimposes on FPHL in elderly women 3
• Can be triggered by medications, nutritional deficiencies, systemic illness, or metabolic dysfunction 7

Mandatory Workup

Androgen Assessment (Required)

• Must evaluate circulating androgens in all women with FPHL 1
• Measure total testosterone using high-quality assay (preferably LC/MS) and free testosterone 1
• Red flag: Sudden exacerbation of hair loss with virilizing signs warrants evaluation for androgen-producing tumors 3

Optional but Recommended Testing

The following should be measured to identify treatable contributing factors 1:

• Thyroid function: Hypothyroidism can cause telogen effluvium and impair hair regrowth 1
• Iron studies (ferritin): 29% of FPHL patients show iron deficiency, though relationship to hair loss remains uncertain 1
• Vitamin D: 62% of FPHL patients have low 25-hydroxyvitamin D levels 1
• Zinc levels: Mean zinc levels lower in FPHL patients (15% have deficiency) 1
• Prolactin: 7.2% of FPHL patients have elevated prolactin 1

Clinical Assessment Approach

History and Examination

• Pattern recognition: Assess for central thinning vs frontal recession vs patchy loss vs diffuse thinning 1
• Look for exclamation mark hairs (broken hairs at margins) suggesting alopecia areata 7
• Examine for scalp inflammation, scaling, or scarring 1
• Document medication history (drug-induced anagen effluvium can mimic diffuse alopecia areata) 7

Dermoscopy

• Can differentiate FPHL from alopecia areata (yellow dots, dystrophic hairs) and scarring conditions 7
• Assessment is primarily clinical; biopsy reserved for diagnostic uncertainty 1

Additional Differential Considerations

Less Common but Important

• Alopecia areata: Lower prevalence of alopecia totalis/universalis in postmenopausal women compared to younger onset 3
• Tinea capitis: Increasingly observed in postmenopausal women worldwide 3
• Trichotillomania: Shows marked female predominance in elderly with higher psychopathology rates 3
• Tumor metastasis to scalp: Consider in women with underlying breast cancer or other neoplasms 3

Key Clinical Pitfalls

• Do not assume all elderly hair loss is "normal aging"—most cases are androgen-driven and potentially treatable 6
• Do not overlook the possibility of multiple concurrent causes (e.g., FPHL plus telogen effluvium plus nutritional deficiency) 3
• Do not miss frontal fibrosing alopecia, which requires early recognition to prevent irreversible scarring 2
• Do not forget the significant psychological impact—hair loss affects self-esteem, anxiety levels, and quality of life in elderly women 4