Evaluation of Scalp Hair Density and Diameter in the Arab Population: Clinical Office-Based Phototrichogram Analysis

Abstract

Background Knowing normal values of scalp hair thickness and density is beneficial for diagnosing hair disorders, monitoring responses to therapy, performing hair transplants, and conducting relevant research. Such normal values have not yet been studied for Arabs. Objective To assess the hair density and diameter of the Arab population at different scalp sites using phototrichogram. Methods A cross-sectional descriptive study was performed at King Saud University Medical City from December 2021 to August 2022. The study was conducted on Arab adults who were not suffering from any hair disorder. The study was conducted using a questionnaire and clinical examination by phototrichogram. Results A total of 120 participants were enrolled in this study. The mean hair density was 147.1± 7.8 hairs/cm2, and the mean hair diameter was 87±4.9 μm. There were significant differences between hair density (P=0.0001) and diameter (P=0.0001) in different regions of the scalp. Females had higher hair density than males at occiput (P=0.038). Conclusion Arab hair has a higher thickness and lower density than hair of other ethnicities. This needs to be considered when diagnosing and/or treating hair problems in Arabs.

AP collagen peptides (APCPs) promote hair growth by activating the GSK‐3β/β‐catenin pathway and improve hair condition

“…Phototrichogram studies have confirmed that the density and diameter of hair decrease with chronological aging 26 . To investigate the effect of APCPs on hair thickness, the diameter of hair in mice was measured.…”

“…Phototrichogram studies have confirmed that the density and diameter of hair decrease with chronological aging. 26 To investigate the effect of APCPs on hair thickness, the diameter of hair in mice was measured. The thickness of hair from the APCPs600 and APCPs900 groups of mice was increased compared with the vehicle group (Figure 6A,C).…”

Quantitative measurement of hair diameter diversity as a diagnostic indicator of androgenetic alopecia in Korean males: A cross-sectional study

“…This is particularly relevant considering that Korean individuals typically have thicker hair compared to those of Caucasian ethnicity. 14 , 15 , 16 , 17 , 18 , 19 Additional analysis, not limited to the fixed HDD cutoff, involving receiver operating characteristic curve evaluation for various hair diameter thresholds, indicated that the 45-μm threshold not only provides the highest AUC of 0.884, suggesting enhanced diagnostic accuracy for AGA, but also attains a peak Youden index at an optimal cutoff ratio of 21.65%. This finding closely aligns with the conventional 20% threshold, underscoring that the established HDD ≥20% remains a valid benchmark even in a different ethnicity.…”

“…However, since the study was based on Caucasians, the 40-μm criterion may not be appropriate for Asians, who typically have thicker hair compared to Caucasians. 14 , 15 , 16 , 17 , 18 , 19 Therefore, our study aims to reevaluate the HDD ≥20% criteria through quantitative measurement of hair thickness and, moreover, to refine the criteria to be more appropriate for Koreans.…”