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When addressing hair loss, a systematic approach can minimize frustrations for physicians and patients alike.
San Francisco - Simple tools and a straightforward approach can help dermatologists address the frustrating problem of hair loss, an expert says.
When such a patient presents, she says, "We are concerned that we will not know what to do with the big bag of hair the patient brings, and that we may not have anything to offer."
Dr. Price adds that she finds a hair card indispensable when examining the hair and scalp. The card is white on one side - to contrast with dark hair - and black on the other - to contrast with white or blonde hair - and it is the easiest way to distinguish hair tips that are broken; or tips that are tapered, as with new growth; or miniaturized hairs, as occur in androgenetic alopecia (AGA), she says. A piece of white paper can also be used.
Dr. Price says patients commonly use the term "hair loss," and dermatologists must determine if the main issue is widespread thinning or less hair on the scalp, or whether profuse shedding or dropout is the main concern.
In AGA, she says, "There typically is no associated profuse shedding, although an episode of telogen effluvium - for example, post-partum effluvium - may uncover a latent AGA when the hair does not fully return to its previous density."
The pathophysiology of AGA involves increased 5 alpha reduction of testosterone to DHT in the genetically susceptible hair follicles, Dr. Price says.
"DHT activates the genes that are responsible for miniaturization of the follicles. Miniaturization represents two processes: shortening of the anagen phase, so that the hair becomes increasingly shorter, and does not grow as long; it also represents the hair matrix becoming smaller, so hair becomes finer."
When examining women with hair loss, Dr. Price says, "Women with AGA don't lose their frontal hairline, even if the hair is very thin behind the hairline."
In addition, she says women with AGA may note that their ponytails have become smaller, that their distal ends have become wispy, or that they are cutting their hair shorter to make it look fuller.
When working up new patients, "I check their TSH, CBC, ferritin, TIBC and iron levels to make sure I haven't missed something." Having normal ferritin levels won't grow more hair, "But the consensus is that patients will respond better to treatment for their hair loss."
It is also important that patients consume adequate protein, she says - "real food, not protein powders. We also ask what medicines they are taking, because some medications can cause hair loss."
Differential diagnosis
Dr. Price says it is important to differentiate AGA from senescent alopecia - she prefers the term "age-related thinning" - because this will help guide treatment (Price VH, Sawaya ME, Headington JT, Kibarian-Skelsey MK. J Invest Dermatol. 2001;117:434(Abs)).
"While AGA can develop from the teen years onward and occurs more in the frontal and temporal regions, senescent thinning begins generally after age 60. The pattern may be more diffuse, but there also may be somewhat greater thinning over the frontal/temporal scalp compared to the occipital scalp."
The reason there is controversy about whether AGA and age-related thinning are indeed separate entities is that, histopathologically, "They look identical, with follicular downsizing in both conditions (Price VH, Sawaya ME, Headington JT, Kibarian-Skelsey MK. J Invest Dermatol. 2001;117:434(Abs)).
"When gene array studies of scalp biopsies from patients with AGA and with age-related thinning are compared, the gene expression profiles are totally different (Mirmirani P, Karnik P et al. J Invest Dermatol. 2006;126:81(Abs))," Dr. Price says.