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Published on: March 9, 2015
Prevalence of male pattern hair loss in 18-49 year old men
T Rhodes1, C J Girman, R C Savin
1Department of Epidemiology, Merck Research Laboratories, West Point, PA 19486, USA.
Background:
Previous studies investigating the prevalence of male pattern hair loss (MPHL) typically used biased samples of men recruited from clinical populations which may limit generalizability of findings to broader populations.
Objective:
To obtain an updated and improved estimate of the occurrence of MPHL in healthy men residing in the community.
Methods:
Community-based sample of healthy men aged 18-49 years participated in a study investigating the effects of MPHL. Participants completed a brief questionnaire self reporting degree of hair loss, general health-related quality of life (HRQL) and hair-loss-specific measures. A trained observer also rated each participant using standardized classification for MPHL.
Results:
The proportion of men with moderate to extensive hair loss (type III or greater) was 42%. The proportion of men with moderate to extensive hair loss increased with increasing age, ranging from 16% for men 18-29 years of age to 53% of men 40-49. Twelve percent of the men were classified as having predominantly frontal baldness (type A variants).
Conclusions:
MPHL, especially frontal baldness, may be more common than previously reported.
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