Premature graying of hair

Abstract

Premature graying is an important cause of low self-esteem, often interfering with socio-cultural adjustment. The onset and progression of graying or canities correlate very closely with chronological aging, and occur in varying degrees in all individuals eventually, regardless of gender or race. Premature canities may occur alone as an autosomal dominant condition or in association with various autoimmune or premature aging syndromes. It needs to be differentiated from various genetic hypomelanotic hair disorders. Reduction in melanogenically active melanocytes in the hair bulb of gray anagen hair follicles with resultant pigment loss is central to the pathogenesis of graying. Defective melanosomal transfers to cortical keratinocytes and melanin incontinence due to melanocyte degeneration are also believed to contribute to this. The white color of canities is an optical effect; the reflection of incident light masks the intrinsic pale yellow color of hair keratin. Full range of color from normal to white can be seen both along individual hair and from hair to hair, and admixture of pigmented and white hair is believed to give the appearance of gray. Graying of hair is usually progressive and permanent, but there are occasional reports of spontaneous repigmentation of gray hair. Studies evaluating the association of canities with osteopenia and cardiovascular disease have revealed mixed results. Despite the extensive molecular research being carried out to understand the pathogenesis of canities, there is paucity of effective evidence-based treatment options. Reports of repigmentation of previously white hair following certain inflammatory processes and use of drugs have suggested the possibility of cytokine-induced recruitment of outer sheath melanocytes to the hair bulb and rekindled the hope for finding an effective drug for treatment of premature canities. In the end, camouflage techniques using hair colorants are outlined.

Premature Hair Graying: Profiling the Scalp Anatomical Patterns of Occurrence in Tanzania

“…While the onset, pattern and progression are random and diverse there are notable differences between and within gender and age categories. Studies have shown a sex dimorphic pattern of premature hair graying-with males depicting temporal scalp region initially followed by the vertex of the scalp while in women graying starts with the perimeter of the hair line and affecting all scalp regions equally [2]. Other studies reports different patterns of onset with men's first onset involving the temporal and occipital regions while women's initial onset involving the frontal region.…”

“…PHG is defined as the first appearance of several gray hairs before the age of 20 among Caucasians, 25 years among Asian races, 30 years among people of the black race or when an individual acquires 50% of gray scalp hair before age 50 year irrespective of the race [3]. Following the onset of PHG the graying tends to be progressive and permanent but spontaneous re-pigmentation in the early stages of canities can occur due to melanogenesis in the deactivated bulbar melanocytes [2]. The process leading to normal hair graying may include irreversible defects in the self renewal and/ or development of follicular melanocyte stem cells gradual decrease of melanin production in the affected hair follicle over time and a drop in the catalase enzyme which stops hydrogen peroxide from breaking down melanin [4].…”

“…The exact etiology and pathophysiology is unknown. But the role of genetics via autosomal dominant pattern, autoimmune disorders, smoking and trace element deficiencies have all been implicated [2,5].…”

“…Hair plays a vital role in the physical appearance and identity and has a further covert role in social communication. Studies have shown that PHG has adverse effects on self-esteem, socio-cultural acceptance, appearance of the affected individual and other subtle social consequences [1,2]. Extreme cases of PHG have been linked with social stigma, discrimination, difficulties in marriage, perception of one being older of their age and loss of health and vigor.…”

“…overt health effects, sufferers often report an enormous social and emotional burden [1,2]. PHG is defined as the first appearance of several gray hairs before the age of 20 among Caucasians, 25 years among Asian races, 30 years among people of the black race or when an individual acquires 50% of gray scalp hair before age 50 year irrespective of the race [3].…”