Early Trichoscopic Changes of Minoxidil Therapy in Male Pattern Hair Loss: A Prospective Cohort Study

Abstract

Background:

Minoxidil 5% is a primary treatment for male pattern hair loss, but initial increased shedding can reduce compliance. While effective, early changes are not visible to the naked eye. Trichoscopy is a rapid, cost-effective tool for diagnosing hair disorders, yet no studies have examined its role in assessing early minoxidil effects. This study aims to evaluate trichoscopic changes in early minoxidil therapy to improve patient compliance.

Methodology:

A prospective cohort study was conducted from February 2019 to August 2020 at MGM Medical College and MY Hospital, Indore. Male patients with hair loss were evaluated using trichoscopy by a single observer. Other causes of hair loss were excluded.

Results:

Minor adverse effects were reported in 45.5% of subjects, with 20% experiencing scalp dryness, 11% increased shedding, and 14% both. Overall, 70% of patients were satisfied with minoxidil therapy. The mean hair loss duration was 13 months, and the most common presentation was N-H grade III. Family history was positive in 78 subjects.

Conclusion:

Trichoscopy enhances early assessment of minoxidil therapy in male pattern hair loss, improving satisfaction and compliance. Positive changes can be observed within one month, encouraging continued treatment adherence.

INTRODUCTION

Androgenetic alopecia or patterned hair loss is most common type of hair loss seen in both men and women[1] characterized by stepwise miniaturization of hair follicle starting from midfrontal and temporal scalp and reaching to posterior scalp. Miniaturization of hair follicles is due to alteration in hair cycle dynamics leading to transformation of terminal hair follicle into vellus one.[2] In men, pattern hair loss occur as a result of combination of genetic predisposition and the effect of androgens; hence, the term androgenetic alopecia (AGA) is often applied.[3] A significant impairment in quantity of life is seen in patients suffering from AGA and is known to affect >50% of them over 50 years of age. Due to progressive nature of the disease, treatment should be started early and extended to maintain efficacy.[4,5,6] The Food and Drug Administration (FDA) approved treatment for AGA are minoxidil and oral finasteride;[3] however, compliance to treatment is not good and dropouts are common because therapy takes longer duration to produce noticeable results. Rudnicka et al.[7] established dermoscopic criteria for diagnosis of androgenic alopecia and also suggested the term trichoscopy (for dermoscopy of hair and scalp). Trichoscopy allows visualization of hair and scalp structures at a 20-100 fold magnification and sometimes higher up to 160 fold. Recently, trichoscopy has shown to be a rapid, easy, low cost, novel, and efficient method to screen and diagnose hair disorders, including patterned hair loss.[8,9] Dermatoscopy can be a useful tool to demonstrate hair diameter diversity due to progressive miniaturization before clinical baldness is visible and is characteristic of androgenetic alopecia. However, in spite of theoretical possibilities, the role of trichoscopy in monitoring disease progression or effect of therapy has not been utilized. Therefore, a systematic study is required to determine the early trichoscopic changes in variables associated with minoxidil therapy so that minoxidil recipients can appreciate changes of therapy and compliance could be improved.

Objectives

1. To measure the trichoscopy-related variables of male pattern hair loss.

2. To assess the trichoscopy-related variables of male pattern hair loss during follow up visits.

3. To compare the changes in trichoscopy-related variables of male pattern hair loss before and after minoxidil therapy.

MATERIAL AND METHODS

This prospective cohort study (Feb 2019–Aug 2020) included male patients (18–40 years) with trichoscopic-confirmed MPHL at MGM Medical College. Patients with systemic illness, inconclusive diagnosis, or medication history were excluded.

METHODOLOGY

This study, approved by the ethics committee, included 200 males with hair loss at MY Hospital, Indore. After consent, patients were assessed using the Modified Norwood-Hamilton criteria, and trichoscopy ruled out other causes.

Trichoscopic examination

Trichoscopy is an easy, rapid, noninvasive, and reliable tool for the diagnosis of hair disorder. All patients were explained about the trichoscopy before the examination. A midline partition was done by separating the hairs from midline, trichoscope was put in midline 3 cm above the anterior hair line in the frontal area, and three images were captured in personal computer by putting the trichoscope in three different sites in midline, and similarly the occipital area was examined 3 cm above posterior hair line. We counted trichoscopic variables of male pattern hair loss in all three images of the frontal and occipital area, respectively. Trichoscopic analysis of hair related variables showing more pronounced changes on frontal scalp compared to occipital scalp suggest patterned hair loss.[10]

Trichoscopic criteria of pattern hair loss

In 2009, Rakowska and Rudnicka et al. proposed videodermoscopic criteria for pattern hair loss. The major and minor criteria are as follows:

Major criteria

1. More than four yellow dots in four images at a 70-fold magnification in the frontal area;

2. Lower average hair shaft thickness in the frontal area as compared to occiput;

3. More than 10% thin hairs (<0.03 mm) in the frontal area.

Minor criteria

1. Ratio of number of vellus hairs in frontal to occipital area >1.5:1;

2. Ratio of the number of single hair pilosebaceous units of frontal to occipital area >2:1;

3. Ratio of hair follicles with perifollicular discoloration in frontal to occipital area >3:1.

Fulfillment of two major criteria or one major and two minor criteria is required for the diagnosis of pattern hair loss.[11]

However, in our study, these above criteria have been modified to be accessible in resource-poor settings. These modifications are as follows:

Changes in hairs

• Vellus-like hairs—thin miniaturized hair.

• Anisotrichosis—heterogeneity in hair shaft thickness.

Changes around follicles

• Peripilar sign: brown discoloration from lymphocytic infiltrates.

• Yellow dots: follicular openings with keratotic material or sebum.

• Single hair follicular unit: a unit with only one emerging hair.

Overview of dermoscope used in our study

We used a digital nonpolarized dermoscope with a USB connection (compatible with USB 2.0 and 1.1), a color CMOS sensor, and a 24-bit DSP for high-speed processing. It offers a resolution of 640 × 480, magnification from 50× to 500×, and an adjustable white LED light source with eight LEDs.

Statistical analysis

Data were analyzed using SPSS v20.0. Categorical variables were in numbers (%), and continuous variables as mean ± SD and median. Repeated measures ANOVA was used, with P < 0.05 as significant.

OBSERVATION AND RESULTS

We recruited male patients aged 18-40 years, with 70% in the 20-30 age group and a mean age of 27.19 years. The mean hair loss duration was 13 months, with grade III N-H being the most common. Family history was positive in 78 cases. Significant trichoscopic improvements were observed, especially in the frontal area. Of 200 subjects, 70% were satisfied with minoxidil therapy. Minor adverse effects occurred in 45.5%, including scalp dryness (20%) and increased shedding (11%), while 54.5% reported no side effects [Tables 1-3].

Table 1.

Baseline characteristics of study subjects (n=200)

Characteristics	Range
Age range	18 − 40 years
Mean age	27.19 years±5.24SD
Mean duration of illness	11.6 months±5.02SD
Norwood-Hamilton grading	Grade I: 1 Grade II: 50 Grade III: 93 Grade IV: 45 Grade V: 11
Family history of pattern hair loss	Positive: 78 Negative: 122

Table 3.

Effect and patient satisfaction rate of minoxidil therapy (n=200)

	Minoxidil effect seen	Minoxidil effect not seen
Therapy satisfied subjects	140	0
Therapy unsatisfied subjects	60	0

Table 2.

Changes in trichoscopic variables in the frontal and occipital area (n=200)

Variables	Frontal			Occipital
	Baseline (mean value)	Follow-up 2 (mean value)	P	Baseline (mean value)	Follow-up 2 (mean value)	P
Anisotrichosis	23.035	34.005	0.001*	11.29	17.73	0.001*
Vellus-like hairs	12.41	22.61	0.001*	6.73	10.72	0.005*
Peripilar sign	7.175	0.985	0.001*	3.49	0.385	0.001*
Yellow dots	2.105	0.365	0.001*	0.43	0.205	0.003*
Single hair follicular unit	13.105	7.4	0.001*	6.645	4.395	0.005*
Mean hair count	22.579	26.865	0.001*	23.219	26.184	0.001*

P value was calculated using repeated measure ANOVA test, and P<0.05 was considered statistically significant. Statistically significant P values have been marked with *

DISCUSSION

Androgenetic alopecia is one of the most common hereditary androgen dependent hair disorder, induced by androgens in genetically predisposed individual. It is characterized by progressive diffuse thinning of hairs, recession of hairline and balding of vertex.[12] There is growing importance of treating this condition, as it has a significant psychological impact on affected patients and because of emphasis that modern society lays on looking good.[13] Till now, minoxidil and finasteride are only FDA-approved therapeutic modalities available for treatment of androgenetic alopecia, and so treating AGA has always been challenging.[3,14] There is limited literature available showing implication of dermoscopy in monitoring the response of early minoxidil therapy. In our study, we recruited male patients presenting with complaints of hair loss in the age group of 18-40 years with maximum patients (37.5%) in the age group of 20-25 years. Mean age of patient was 27.19, which was comparable with 27.5 years and 30.6 years in studies by Prachi Chandankumar Gjjar et al.[13] We wanted to assess the trichoscopic capabilities in early disease and early therapy. The mean duration of illness in our study was 11.6 months. We also assessed patient satisfaction rate with effect of minoxidil therapy at the end of 2 months and found that 140 (70%) patients were satisfied with the therapy and 60 (30%) were not satisfied. We found that satisfaction rates of minoxidil therapy decreases if subjects were not analyzed with trichoscope. In the present study, mean hair count increased significantly at the end of 2 months with mean values 22.57 at baseline to 26.86 at second follow up (P = 0.001).[15] We found significant increase in anisotrichosis in our study with mean 23.035 at baseline to 34.005 at the end of 2 months (P = 0.001). Comparable results were found in study by Prachi Chandankumar Gajjar et al.[13] with a significant increase in hair diameter diversity (P = 0.01) at the end of 4 months of 5% minoxidil therapy. This may be due to the growth of new hairs, which are sometimes not perceived by naked eye, but can only be visualized by a dermoscope. The number of vellus-like hair increased significantly with a mean value of 12.41 at baseline to 22.65 at second follow-up after 2 months of therapy (P = 0.000), which is due to the growth of new hairs. After a thorough review, we were unable to find any study in previous literature comparing the number of vellus-like hairs before and after 5% minoxidil therapy in patients with male AGA. There was 86.27% reduction in peripilar sign with mean 7.175 at baseline to 0.985 at the end of 2 months (P = 0.00); this was comparable to the study in which 95% reduction in PPS was seen after 6 months of 2% minoxidil therapy in patients with FPHL. However, noncomparable results were found in the study by Prachi Chandankumar Gjjar et al.[13] in which no significant reduction (P = 0.96) in peripilar sign was seen after 4 months of 5% minoxidil therapy in patients with MPHL. Our study showed an 82.66% reduction in yellow dots after 2 months (mean: 2.105 to 0.365, P = 0.00), comparable to Ahmed EI-Garf et al.’s 75% reduction (P = 0.001).

We found a 43.87% reduction in the number of single hair follicular unit with a mean value of 13.105 at baseline and 7.4 after 2 months of minoxidil therapy (P = 0.001). We did not recruit female subjects in our study because telogen effluvium is difficult to differentiate from pattern hair loss by trichoscopy in females.

CONCLUSION

Trichoscopy aids early assessment of minoxidil therapy in young males with pattern hair loss, enhancing satisfaction and compliance as early as one month.

Conflicts of interest

There are no conflicts of interest.

Funding Statement

Nil.