Abstract
Introduction: Androgenetic alopecia (AGA) is the most common type of hair loss. Platelet-rich plasma (PRP) and mesotherapy (MZT) injections of various solutions fortified with growth factors are popular treatment options for AGA. The aim of this study was to compare the efficacy of RPP and MZT products in the treatment of AGA. Methods: This retrospective study included 72 AGA patients treated with two PRP formulations and two MZT products, administered manually or with a gun injector. Hair parameters (hair thickness, hair density, and hair count) on frontal and vertex areas were measured before and after 6 months. Results: Over 6 months, trichoscopic parameters showed significant intragroup and intergroup variability. MZT1 and PRP2 groups exhibited statistically significant improvement in most parameters, while MZT2 significantly increased vertex hair density. Hair thickness changes differed significantly between PRP1 and PRP2 groups (unadjusted p value <0.001) and possibly between MZT1 and PRP1 groups (unadjusted p value = 0.049) in both regions. Discussion: Injections of PRP and MZT formulations can significantly enhance trichoscopic parameters in AGA patients within a 6-month period, but the extent of improvement varies among different PRP and MZT products.
Introduction
Androgenetic alopecia (AGA) is a type of non-scarring alopecia, which affects more than 50% of population by the age of 70 [1]. It involves the progressive miniaturization of androgen-dependent hair follicles in genetically predisposed individuals resulting in hair thinning and alopecia with a patterned distribution [1]. Despite its frequency, only oral finasteride and topical minoxidil are officially approved for the treatment of AGA worldwide [1].
Platelet-rich plasma (PRP) injections, adipose tissue-derived stem cells (ADSCs), as well as culture media containing ADSC secretions (ADSC-conditioned media or ADSC-CM) or stem cell-derived exosomes are newer regenerative options for the treatment of AGA [2]. Platelets and stem cells release several growth factors, namely, vascular endothelial growth factor (VEGF), insulin-like growth factor (IGF), epidermal growth factor (EGF), and transforming growth factor beta (TGF-beta), and other cytokines, such as phosphodiesterase 2 and prostaglandin E2 [3, 4]. They promote and support hair growth by stimulating follicular stem cells, inducing angiogenesis and regulating inflammation around hair follicles [3]. Several studies have been performed, both in vivo and ex vivo, to demonstrate the efficacy of the aforementioned regenerative modalities in hair growth with conflicting but mainly positive results [4, 5].
Mesotherapy (MZT) is the technique of injecting a product into the dermis and subcutaneous tissue in order to rejuvenate the skin, induce lipolysis, or promote hair growth [6]. Various products exist with different formulations marketed to induce hair growth and sustain hair loss. They may contain vitamins, such as biotin, minerals, such as copper, plant extracts with antiandrogenic properties (saw palmetto), and ADSC-CM fortified with recombinant growth factors. Even though these products have been used for years, clinical evidence is lacking [7].
In this retrospective study, we compare the efficacy of intradermal injections with PRP or with commercial preparations on hair growth based on phototrichographic analyses of our patients who underwent these procedures in our department between 2011 and 2020.
Materials and Methods
Study Design
This is a retrospective study based on the electronic records and the phototrichographic data of patients visiting the outpatient department of dermatolovenerology of University Hospital Kralovske Vinohrady in Prague, Czech Republic, between January 1, 2011 and December 31, 2020. The study was registered with Clinicaltrials.gov (NCT05129800). Written informed consent was obtained from all participants. The study was approved by the Ethical Review Board of our hospital (EK_VP/59l0l202I).
Study Population
We included all patients aged 18 and above visiting our clinic department from January 1, 2011 to December 31, 2020, meeting the following criteria: (1) male or female patients diagnosed clinically/histologically/trichoscopically with AGP (stage II to V per Hamilton-Norwood Scale or stage I to III according to Ludwig Classification) [8, 9]; (2) underwent either PRP or MZT injections at our dermatology department during the aforementioned period; (3) received no treatment or were treated consistently for more than 6 months for AGP without medication changes before injections (e.g., finasteride, minoxidil, antiandrogens, hormonal substitution, hormonal contraceptives, phototherapy/laser, cryotherapy, microneedling); (4) underwent trichoscopic examination and phototrichographic evaluation with our digital dermatoscope before treatment, a month after the last injection, and 3 months posttreatment. Trichoscopic photos and phototrichographic analyses were taken from the midfrontal and vertex areas – defined as the intersection of the midsagittal line and the line through the external auditory canals in the coronal plane.
We excluded all patients with the following criteria: (1) patients with other types of alopecia, other than AGP; (2) patients with two or more diagnoses of hair loss, for example, AGP and telogen effluvium or alopecia areata; (3) patients who started concomitant medication for hair loss within 6 months of treatment with PRP or MZT (see previous paragraph); (4) patients who underwent hair transplantation to the vertex/midfrontal area; (5) patients with no trichoscopic examination/phototrichographic evaluation; (6) Patients lost to follow-up or opted to withdraw from the particular treatment.
Data Collection
From patient records, we extracted the following data: age, gender, type of alopecia, severity of alopecia, past and current medications, type, and duration of selected injection treatment. Severity of alopecia was classified as mild (Norwood-Hamilton I–II, Ludwig I), moderate (Norwood-Hamilton IIa–IV, Ludwig II) and severe (Norwood-Hamilton IVa–VII, Ludwig III). From our phototrichogram (VisioMed, Visiomed AG, Germany), we obtained trichoscopic images and phototrichographic evaluations, including total hair count, hair density (number of hairs per cm2), and hair thickness in μm. Trichoscopic photos were taken at ×30 magnification. Macroscopic photos were also obtained, but they were not standardized and they were not evaluated.
PRP Preparation
For PRP injections, 8–10 mL of blood was withdrawn from each patient into a tube containing either 3.8% sodium citrate together with either enoxaparin gel (Meaplasma®; Inviva-Tech LLC, Russian Federation) or thixotropic cell-separation gel (RegenBCT®; Regen Lab SA, Switzerland). The tubes were centrifuged at either 3,900 rpm for 10 min (Meaplasma) or at 1,500 g for 5 min (RegenBCT), resulting in four layers: a cell-rich layer at the bottom of the tube covered by the separating gel, a PRP layer on top of the gel, and a platelet-poor plasma (PPP) layer at the top. The tube was gently agitated in order to mix the PPP with the PRP. The solution, ca. 4–5 mL, was withdrawn with a needle and injected to the frontoparietal region of the scalp-using either a syringe and a 4 mm needle or an injector. Injections were spaced 0.5–1 cm apart. PRP was applied once every month for 3 months. Macroscopic and digital phototrichographic photos were taken before the beginning of treatment, 1 month after the last injection, and 3 months after the end of treatment.
MZT Products for Hair Loss
For MZT, 5 mL of saline solution was withdrawn using a needle and released to the selected ampule containing adipose tissue stem cell-conditioned media and mixture of recombinant growth factors, in a powder form. During the period under study, preparations from two different companies were used differing in the combination and concentration of ingredients. Active ingredients of the first preparation (DermaHeal Stem C’Rum HL®; Caregen Co., South Korea) were sh-oligopeptide-2 (IGF-1), sh-Polypeptide-1 (bFGF), sh-Polypeptide-9 (VEGF), ADSC-CM, copper tripeptide-1, and biotin. Concentrations of each recombinant growth factor (peptide) were stated to be 10 ppm. The second preparation (allstem.®; Scimed Pharma CY Ltd, Cyprus) contained rh-Oligopeptide-1 (EGF), rh-Polypeptide-19 (TGFa), rh-Polypeptide-9 (VEGF), ADSC-CM, niacinamide, and biotin. ADSC-CM concentration was 6% w/v but concentrations of peptides were not provided.
After the injection of normal saline, the ampule was gently agitated in order to disperse the powder and injected to the scalp-frontoparietal region using either a syringe and a 4 mm needle or a gun injector. The injections were spaced 0.5–1 cm apart.
MZT was repeated every 2 weeks for 6 times (allstem.) or every 1 or 2 weeks for 8 times (DermaHeal Stem C’Rum HL) times according to the protocol recommended by each company. Macroscopic and phototrichographic photos were taken before the beginning of treatment, a month after the last injection and 3 months after the end of treatment.
Data Analysis
Patients were divided into four groups based on type of treatment: PRP1, PRP2, MZT1, and MZT2 for patients treated with Meaplasma, RegenBCT, DermaHeal Stem C’Rum HL or allstem., respectively. Descriptive statistics were used to describe patient characteristics; frequencies and percentages were provided for categorical variables. Quantitative variables were represented as mean and standard deviation (SD) for continuous variables or median and interquartile range for nonparametric continuous variables. Concerning age stratification, agreement between the study groups was checked using two sample Kolmogorov-Smirnov test. For the analysis of observed data, t-test for two independent or dependent means were used as well as, Mann-Whitney U test when needed [10]. The statistical significance level was set to 0.05. All statistical analyses were performed using Microsoft Excel (version 2010; Microsoft Corp, Redmond, WA, USA) and IBM SPSS Statistics (Version 24.0: IBM Corp, Armonk, NY, USA).
Results
We identified 752 patients who underwent PRP or other MZT injections in our clinic during the study period. Based on our exclusion criteria, 681 patients were not considered eligible for the study, and the remaining 72 were divided into four groups according to the type of treatment they received (online suppl. Fig. 1; for all online suppl. material, see https://doi.org/10.1159/000539105). Data used in this study are provided in an online supplementary file (online suppl. Dataset).
Demographics
Out of 72 patients, 51 were females and 21 males (Table 1). The average age on treatment was 41.11 ±11.42 years. Patients on MZT2 were on average the youngest and those under MZT1 were the oldest (32.13 ± 4.21 years vs. 49.95 ± 9.56 years, respectively). Almost all patients (91.7%) were diagnosed with mild-to-moderate alopecia according to Norwood-Hamilton or Ludwig scales.
Demographic data of participants included in the study
Variable . | MZT1 (n = 22) . | MZT2 (n = 16) . | PRP1 (n = 20) . | PRP2 (n = 14) . | Total (n = 72) . | p value . |
---|---|---|---|---|---|---|
Age at treatment initiation, years | <0.001 | |||||
Mean±SD | 49.95±9.56 | 32.13±4.21 | 39.93±10.68 | 39.4±11.48 | 41.11±11.42 | |
Median (range) | 50.5 (37–72) | 33.0 (23–38) | 41.0 (18–55) | 38.5 (21–73) | 40.0 (18–73) | |
Gender, n (%) | 0.208 | |||||
Females | 19 (86.4) | 9 (56.3) | 13 (65.0) | 10 (71.4) | 51 (70.8) | |
Males | 3 (13.6) | 7 (43.8) | 7 (35.0) | 4 (28.6) | 21 (29.2) | |
Clinical severity, n (%) | 0.865 | |||||
Mild | 9 (40.9) | 6 (37.5) | 12 (60.0) | 7 (50.0) | 34 (47.2) | |
Moderate | 11 (50.0) | 8 (50.0) | 7 (35.0) | 6 (42.9) | 32 (44.4) | |
Severe | 2 (9.1) | 2 (12.5) | 1 (5.0) | 1 (7.1) | 6 (8.3) |
Variable . | MZT1 (n = 22) . | MZT2 (n = 16) . | PRP1 (n = 20) . | PRP2 (n = 14) . | Total (n = 72) . | p value . |
---|---|---|---|---|---|---|
Age at treatment initiation, years | <0.001 | |||||
Mean±SD | 49.95±9.56 | 32.13±4.21 | 39.93±10.68 | 39.4±11.48 | 41.11±11.42 | |
Median (range) | 50.5 (37–72) | 33.0 (23–38) | 41.0 (18–55) | 38.5 (21–73) | 40.0 (18–73) | |
Gender, n (%) | 0.208 | |||||
Females | 19 (86.4) | 9 (56.3) | 13 (65.0) | 10 (71.4) | 51 (70.8) | |
Males | 3 (13.6) | 7 (43.8) | 7 (35.0) | 4 (28.6) | 21 (29.2) | |
Clinical severity, n (%) | 0.865 | |||||
Mild | 9 (40.9) | 6 (37.5) | 12 (60.0) | 7 (50.0) | 34 (47.2) | |
Moderate | 11 (50.0) | 8 (50.0) | 7 (35.0) | 6 (42.9) | 32 (44.4) | |
Severe | 2 (9.1) | 2 (12.5) | 1 (5.0) | 1 (7.1) | 6 (8.3) |
p < 0.05 is statistically significant.
SD, standard deviation; n, number.
Efficacy of MZT Injections
A total of 38 patients were injected MZT products. Twenty-two patients were treated with the MZT1 formulation and 16 with the MZT2 formulation. The mean values in hair count, thickness, and density in both frontal and vertex areas before treatment initiation and after 6 months are shown in Table 2. A statistically significant increase in all trichoscopic variables was observed in MZT1, particularly in the frontal region (p < 0.05). In MZT2 group, significant improvement in hair thickness was noted in the vertex area (p < 0.01) but not in the other parameters. An example is provided in online supplementary Figure 2.
Trichoscopic features from the frontal and vertex areas of patients from MZT1 and MZT2 groups before treatment and after 6 months
Variable . | MZT1 (n = 22) . | p value . | MZT2 (n = 16) . | p value . | ||
---|---|---|---|---|---|---|
Time point, month . | 0 . | 6 . | 0 . | 6 . | ||
Frontal area | ||||||
Hair count, mean±SD | 241.86±83.76 | 286.23±78.92 | 0.0071 | 255.56±70.21 | 260.38±73.13 | 0.3974 |
Hair thickness, mean±SD, μm | 77.65±12.23 | 82.63±8.51 | 0.0227 | 83.56±5.66 | 85.60±7.89 | 0.1075 |
Hair density, mean±SD, n/cm2 | 167.14±36.71 | 187.41±34.42 | 0.0096 | 176.06±23.63 | 169.56±29.02 | 0.2676 |
Vertex area | ||||||
Hair count, mean±SD | 228.03±85.33 | 238.31±78.04 | 0.0367 | 252.41±82.72 | 288.36±82.92 | 0.3639 |
Hair thickness, mean±SD, μm | 77.66±11.89 | 80.90±10.12 | 0.0078 | 77.98±6.31 | 83.61±6.62 | 0.0076 |
Hair density, mean±SD, n/cm2 | 167.57±43.32 | 170.58±30.59 | 0.2033 | 178.91±33.89 | 183.64±47.09 | 0.4681 |
Variable . | MZT1 (n = 22) . | p value . | MZT2 (n = 16) . | p value . | ||
---|---|---|---|---|---|---|
Time point, month . | 0 . | 6 . | 0 . | 6 . | ||
Frontal area | ||||||
Hair count, mean±SD | 241.86±83.76 | 286.23±78.92 | 0.0071 | 255.56±70.21 | 260.38±73.13 | 0.3974 |
Hair thickness, mean±SD, μm | 77.65±12.23 | 82.63±8.51 | 0.0227 | 83.56±5.66 | 85.60±7.89 | 0.1075 |
Hair density, mean±SD, n/cm2 | 167.14±36.71 | 187.41±34.42 | 0.0096 | 176.06±23.63 | 169.56±29.02 | 0.2676 |
Vertex area | ||||||
Hair count, mean±SD | 228.03±85.33 | 238.31±78.04 | 0.0367 | 252.41±82.72 | 288.36±82.92 | 0.3639 |
Hair thickness, mean±SD, μm | 77.66±11.89 | 80.90±10.12 | 0.0078 | 77.98±6.31 | 83.61±6.62 | 0.0076 |
Hair density, mean±SD, n/cm2 | 167.57±43.32 | 170.58±30.59 | 0.2033 | 178.91±33.89 | 183.64±47.09 | 0.4681 |
p < 0.05 is statistically significant.
n, number; SD, standard deviation.
Efficacy of PRP Injections
A total of 34 patients underwent PRP injections. Twenty individuals received PRP isolated using the PRP1 kit and 14 patients using the PRP2 kit. The mean values in hair count, thickness, and density in both frontal and vertex areas before treatment initiation and after 6 months are shown in Table 3. Treatment with PRP2 resulted in a statistically significant improvement in all trichoscopic values in the vertex region, along with enhanced hair thickness in the frontal region (p < 0.05). The PRP1 group exhibited no significant increase in any recorded variable throughout the study period. An example is provided in online supplementary Figure 3.
Trichoscopic features from the frontal and vertex areas of patients from PRP1 and PRP2 groups before treatment and after 6 months
Variable . | PRP1, n (%) n = 20 . | p value . | PRP2, n (%) n = 14 . | p value . | ||
---|---|---|---|---|---|---|
Time point, month . | 0 . | 6 . | 0 . | 6 . | ||
Frontal area | ||||||
Hair count, mean±SD | 193.40±105.68 | 197.20±107.58 | 0.1057 | 153.93±107.00 | 147.57±94.47 | 0.2451 |
Hair thickness, mean±SD, μm | 77.33±16.78 | 76.02±15.86 | 0.0559 | 66.47±14.32 | 72.82±14.47 | 0.0008 |
Hair density, mean±SD, n/cm2 | 156.30±42.89 | 164.30±48.20 | 0.0749 | 139.86±59.41 | 139.00±43.06 | 0.3409 |
Vertex area | ||||||
Hair count, mean±SD | 225.90±96.16 | 225.60±94.42 | 0.2644 | 138.93±92.02 | 156.86±98.65 | 0.0012 |
Hair thickness, mean±SD, μm | 80.36±14.46 | 79.72±15.22 | 0.2005 | 66.11±13.14 | 72.70±16.20 | 0.0009 |
Hair density, mean±SD, n/cm2 | 165.20±40.12 | 165.95±38.01 | 0.3632 | 130.64±48.11 | 144.21±45.40 | 0.0281 |
Variable . | PRP1, n (%) n = 20 . | p value . | PRP2, n (%) n = 14 . | p value . | ||
---|---|---|---|---|---|---|
Time point, month . | 0 . | 6 . | 0 . | 6 . | ||
Frontal area | ||||||
Hair count, mean±SD | 193.40±105.68 | 197.20±107.58 | 0.1057 | 153.93±107.00 | 147.57±94.47 | 0.2451 |
Hair thickness, mean±SD, μm | 77.33±16.78 | 76.02±15.86 | 0.0559 | 66.47±14.32 | 72.82±14.47 | 0.0008 |
Hair density, mean±SD, n/cm2 | 156.30±42.89 | 164.30±48.20 | 0.0749 | 139.86±59.41 | 139.00±43.06 | 0.3409 |
Vertex area | ||||||
Hair count, mean±SD | 225.90±96.16 | 225.60±94.42 | 0.2644 | 138.93±92.02 | 156.86±98.65 | 0.0012 |
Hair thickness, mean±SD, μm | 80.36±14.46 | 79.72±15.22 | 0.2005 | 66.11±13.14 | 72.70±16.20 | 0.0009 |
Hair density, mean±SD, n/cm2 | 165.20±40.12 | 165.95±38.01 | 0.3632 | 130.64±48.11 | 144.21±45.40 | 0.0281 |
p < 0.05 is statistically significant.
n, number; SD, standard deviation.
Pairwise Comparisons
In an attempt to identify the injection method yielding the most substantial improvement in trichoscopic values, we conducted pairwise comparisons to assess the changes in trichoscopic parameters pre- and posttreatment, as presented in Table 4. Significant differences were found in hair thickness, both in the frontal and vertex regions, between MZT1 and PRP1 (p < 0.05), and PRP1 and PRP2 groups (p < 0.001). When comparing other parameters such as hair count and hair density, as well as evaluating the remaining pairs, the differences in the change of trichoscopic values did not reach significance.
Pairwise comparisons of the changes in trichoscopic parameters at the frontal and vertex areas of the four study groups 6 months after treatment initiation
Variable . | MZT1 versus MZT2 . | MZT1 versus PRP1 . | MZT1 versus PRP2 . | MZT2 versus PRP1 . | MZT2 versus PRP2 . | PRP1 versus PRP2 . |
---|---|---|---|---|---|---|
Unadjusted p values . | ||||||
Frontal area | ||||||
Hair count, mean±SD | 0.721 | 1.000 | 0.146 | 1.000 | 1.000 | 0.380 |
Hair thickness, mean±SD, μm | 1.000 | 0.046 | 0.421 | 0.606 | 0.088 | <0.001 |
Hair density, mean±SD, n/cm2 | 0.390 | 1.000 | 0.516 | 0.443 | 1.000 | 0.577 |
Vertex area | ||||||
Hair count, mean±SD | 0.318 | 0.907 | 1.000 | 1.000 | 0.290 | 0.768 |
Hair thickness, mean±SD, μm | 1.000 | 0.046 | 0.606 | 0.357 | 0.237 | <0.001 |
Hair density, mean±SD, n/cm2 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 |
Variable . | MZT1 versus MZT2 . | MZT1 versus PRP1 . | MZT1 versus PRP2 . | MZT2 versus PRP1 . | MZT2 versus PRP2 . | PRP1 versus PRP2 . |
---|---|---|---|---|---|---|
Unadjusted p values . | ||||||
Frontal area | ||||||
Hair count, mean±SD | 0.721 | 1.000 | 0.146 | 1.000 | 1.000 | 0.380 |
Hair thickness, mean±SD, μm | 1.000 | 0.046 | 0.421 | 0.606 | 0.088 | <0.001 |
Hair density, mean±SD, n/cm2 | 0.390 | 1.000 | 0.516 | 0.443 | 1.000 | 0.577 |
Vertex area | ||||||
Hair count, mean±SD | 0.318 | 0.907 | 1.000 | 1.000 | 0.290 | 0.768 |
Hair thickness, mean±SD, μm | 1.000 | 0.046 | 0.606 | 0.357 | 0.237 | <0.001 |
Hair density, mean±SD, n/cm2 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 |
p < 0.05 is considered statistically significant.
n, number; SD, standard deviation.
Discussion
Our results demonstrated that there is an intragroup and intergroup variability in trichoscopic parameters over a period of 6 months. Only in MZT1 and PRP2 groups, we observed statistically significant differences in most parameters (hair count, thickness and density) in frontal and/or vertex regions. Treatment with MZT2 significantly increased the density of vertex hair without major differences in hair density at the frontal scalp. Pairwise comparisons (Table 4) showed that change in hair thickness after 6 months differed significantly between PRP1 and PRP2 groups and possibly between MZT1 and PRP1 groups (unadjusted p value = 0.049) in both vertex and frontal regions.
Several trials have been published regarding PRP treatment of AGA with positive but heterogeneous results. A meta-analysis including ten randomized controlled trials concluded that PRP significantly increases both hair thickness and hair density [5]. Results of another meta-analysis confirmed that PRP only increases hair density, especially in men, without significantly affecting hair diameter [11]. A third meta-analysis study confirmed that hair count and hair diameter were not significantly increased in PRP-treated AGA patients [12]. In our study, patients treated with PRP2, but not with PRP1, showed a significant improvement in all hair parameters in vertex area, as well as increase in hair thickness in the frontal area 6 months after treatment initiation.
Treatment with PRP for AGA can be effective but is influenced by various factors: alopecia severity, duration, patient plasma quality, PRP preparation method, platelet concentration, activation, and application technique [13, 14]. Some factors can be controlled, for example, patients on antiplatelet agents are excluded, but preparation methods lack standardization across studies [13]. Commercial kits vary in blood extraction amount, separation method, centrifugation, and platelet concentration in the final solution [15]. Double-spin centrifugation-prepared PRP was more effective in increasing hair density and diameter than single-spin centrifugation-prepared PRP [13]. Ince et al. [16] showed that different PRP protocols yield varying platelet concentrations and, consequently, different hair density outcomes. The variability in preparation protocols and platelet count may explain the observed differences between PPR1 and PRP2 groups in our study.
Apart from PRP, various formulations can be injected into the scalp for treating AGA [2]. Most studies have explored the impact of intradermal injections of ADSC-CM [2, 4]. In 2012, Fukuoka et al. [17] injected a solution containing ASC-CM, proteins, and vitamins into the scalp of 25 AGA patients. After four monthly injections, patients and investigators subjectively reported increased hair count and density. Another study by Fukuoka and Suga [18] in 2014 involved a 6-month prospective study with 32 patients receiving monthly scalp injections of commercially available ASC-CM. The findings showed a statistically significant rise in hair count, with an increase of 29 hairs/cm2 for males and 15.6 hairs/cm2 for females. In a single-arm study, 1,000 AGA patients received eight 3 weekly intradermal injections of a solution containing recombinant growth factors (VEGF, bFGF, IGF, copper tripeptide, keratinocyte growth factor, thymosin β4) fortified with vitamins, minerals, and amino acids [19]. Following treatment completion, there were statistically significant increases in hair count – 8 hairs/cm2 (frontal region) and 15.5 hairs/cm2 (parietal region) – and in hair diameter – 8 mm (frontal region) and 8 mm (parietal region).
In our study, MZT treatments yielded varied outcomes. Despite both formulations containing ADSC-CM, biotin, and recombinant growth factors, only the MZT1 group exhibited significant increases in hair variables in the frontal and parietal regions. These findings align with existing literature, reflecting a mean rise of 44 hairs/cm2 (hair count), 3 mm/cm2 (hair thickness), and 10 mm/cm2 (hair density) for the frontal region, and 36 hairs/cm2 (hair count), 6 mm/cm2 (hair thickness), and 5 mm/cm2 (hair density) for the vertex. In the MZT2 group, a significant change was observed solely in hair thickness at the vertex.
Several factors may contribute to the differing efficacies between MZT1 and MZT2 groups. In MZT2, a smaller patient count (n = 16 vs. n = 22), younger age (mean age = 32.13 years vs. 49.95 years), and a higher proportion of males (43.8% vs. 13.6%) were observed compared to MZT1. These findings are in discordance with the literature which suggests better responses in males to injectable AGA treatments [13, 18]. Additional factors affecting the lack of significant improvement in MZT2 include varying concentrations and types of recombinant growth factors and ASC-CM, injection method (direct vs. injector device) [20], the quantity of material injected per cm2 and experience of the injector [21].
Study Limitations
Our study was prone to information and measurement biases, and several confounding factors. To address this, we applied strict criteria, leading to the exclusion of over 90% of screened records. Clinical information, determining patient eligibility, relied on our hospital’s digital records, introducing a potential bias. To minimize recall bias, objective quantitative variables were sourced exclusively from our digital phototrichogram, not medical records. The small sample size, reliance on department records, and the 6-month study duration may limit generalizability to the broader population and longer treatment durations.
The four treatment groups exhibited variations in size, recorded demographics, and alopecia severity. Only age significantly varied among groups (p < 0.001) and was considered a confounding factor. The MZT1 group had the oldest participants, with a median age of 50.5 years, and the highest proportion of females (86.4%). Conversely, the MZT2 group had the youngest participants, with a median age of 33 years, and a more even distribution of gender, with 43.8% males.
Conclusion
The administration of both PRP and MZT injections could improve hair density, hair count, and hair thickness in AGA patients in frontal and vertex regions after 6 months. However, the efficacy of all formulations was not uniform, and not all changes in trichoscopic variables reached statistical significance in comparisons among treatment groups. These differences emphasize the need of careful patient and product selection to achieve the optimal results.
Acknowledgments
We thank Adam Whitley, MD, PhD from the department of general surgery, Third Faculty of Medicine, Charles University, and University Hospital Královské Vinohrady for the language review.
Statement of Ethics
The study was reviewed and approved by the Ethical Review Board of our hospital – University Hospital Kralovske Vinohrady (EK_VP/59l0l202I). Written informed consent was obtained from all participants.
Conflict of Interest Statement
The authors have no conflicts of interest to declare.
Funding Sources
This study was not supported by any sponsor or funder.
Author Contributions
A.J.S. was involved in study conception and design, in the acquisition, analysis, and interpretation of data and drafting of the manuscript. P.A., M.A., and D.R. were involved in the critical revision of the manuscript.
Data Availability Statement
The data that support the findings of this study are available within the article and its supplementary materials. Further inquiries can be directed to the corresponding author.