The authors conducted this meta-analysis of randomized controlled trials (RCTs) to assess the effects of photobiomodulation therapy (PBMT) in the treatment of androgenic alopecia (AA). RCTs published in Pubmed, Web of Science, and Embase were systematically reviewed to identify the effects of PBMT in AA patients. The outcome measures included hair density and hair growth. Results were expressed as weighted mean difference (WMD) with 95% confidence interval (95%CI) and a risk ratio (RR) of 95%CI. A fixed-effects model or a randomized-effects model was performed according to the heterogeneity among the included studies. Nine RCTs met the inclusion criteria and were included in this meta-analysis. The mean change from baseline in hair density was 36.78 ± 23.84/cm2 in the PBMT group as compared with 8.88 ± 19.56/cm2 in the control group. Patients who received PBMT had a greater increase in hair density than those treated with a sham device (WMD = 18.56/cm2, 95%CI: 13.22, 23.89; P < 0.001). Moreover, PBMT was associated with a 42.43% increase in hair growth as compared with the sham device treatment (WMD = 42.43, 95%CI: 28.58, 56.28; P < 0.001). A greater rate of patients who were treated with PBMT achieved an improvement in hair regrowth than those with the sham device (RR = 1.32, 95%CI: 1.09, 1.58; P = 0.003). This study indicated that PBMT seemed to be a promising noninvasive treatment for patients with AA since it could improve hair density and stimulate hair growth. However, considering the potential limitations in this study, more large-scale RCTs are needed to verify our findings.

1.
R.
Hu
,
F.
Xu
,
Y.
Sheng
,
S.
Qi
,
Y.
Han
,
Y.
Miao
,
W.
Rui
, and
Q.
Yang
, “
Combined treatment with oral finasteride and topical minoxidil in male androgenetic alopecia: A randomized and comparative study in Chinese patients
,”
Dermatol. Ther.
28
,
303
308
(
2015
).
2.
P.
Avci
,
G. K.
Gupta
,
J.
Clark
,
N.
Wikonkal
, and
M. R.
Hamblin
, “
Low-level laser (light) therapy (LLLT) for treatment of hair loss
,”
Lasers Surg. Med.
46
,
144
151
(
2014
).
3.
M.
Zhang
and
N.
Zhang
, “
Quality of life assessment in patients with alopecia areata and androgenetic alopecia in the People's Republic of China
,”
Patient Prefer. Adherence
11
,
151
155
(
2017
).
4.
M.
Ghanaat
, “
Types of hair loss and treatment options, including the novel low-level light therapy and its proposed mechanism
,”
South. Med. J.
103
,
917
210
(
2010
).
5.
S.
Rangwala
and
R. M.
Rashid
, “
Alopecia: A review of laser and light therapies
,”
Dermatol. Online J.
18
,
3
(
2012
).
6.
M. R.
Avram
and
N. E.
Rogers
, “
The use of low-level light for hair growth: Part I
,”
J. Cosmet. Laser Ther.
11
,
110
117
(
2009
).
7.
Cochrane Handbook for Systematic Reviews of Interventions Version 5.1.0
, edited by
J.
Higgins
and
S.
Green
(
The Cochrane Collaboration
,
Oxford
,
2011
).
8.
D.
Moher
,
A.
Liberati
,
J.
Tetzlaff
, and
D. G.
Altman
, “
Preferred reporting items for systematic reviews and meta-analyses: The PRISMA statement
,”
Br. Med. J.
339
,
b2535
(
2009
).
9.
J. P.
Higgins
,
D. G.
Altman
,
P. C.
Gotzsche
,
P.
Juni
,
D.
Moher
,
A. D.
Oxman
,
J.
Savovic
,
K. F.
Schulz
,
L.
Weeks
, and
J. A.
Sterne
, “
The Cochrane Collaboration's tool for assessing risk of bias in randomised trials
,”
Br. Med. J.
343
,
d5928
(
2011
).
10.
G. H.
Guyatt
,
A. D.
Oxman
,
G. E.
Vist
,
R.
Kunz
,
Y.
Falck-Ytter
,
P.
Alonso-Coello
, and
H. J.
Schunemann
, “
GRADE: An emerging consensus on rating quality of evidence and strength of recommendations
,”
Br. Med. J.
336
,
924
926
(
2008
).
11.
J. P.
Higgins
,
S. G.
Thompson
,
J. J.
Deeks
, and
D. G.
Altman
, “
Measuring inconsistency in meta-analyses
,”
Br. Med. J.
327
,
557
560
(
2003
).
12.
R.
DerSimonian
and
N.
Laird
, “
Meta-analysis in clinical trials
,”
Control Clin. Trials
7
,
177
188
(
1986
).
13.
N.
Mantel
and
W.
Haenszel
, “
Statistical aspects of the analysis of data from retrospective studies of disease
,”
J. Natl. Cancer Inst.
22
,
719
748
(
1959
).
14.
M.
Egger
,
G.
Davey Smith
,
M.
Schneider
, and
C.
Minder
, “
Bias in meta-analysis detected by a simple, graphical test
,”
Br. Med. J.
315
,
629
634
(
1997
).
15.
C. B.
Begg
and
M.
Mazumdar
, “
Operating characteristics of a rank correlation test for publication bias
,”
Biometrics
50
,
1088
1101
(
1994
).
16.
J. L.
Peters
,
A. J.
Sutton
,
D. R.
Jones
,
K. R.
Abrams
, and
L.
Rushton
, “
Performance of the trim and fill method in the presence of publication bias and between-study heterogeneity
,”
Stat. Med.
26
,
4544
4562
(
2007
).
17.
K.
Blum
,
D.
Han
,
M. A.
Madigan
,
R.
Lohmann
, and
E. R.
Braverman
, “‘
Cold
X5 Hairlaser™ used to treat male androgenic alopecia and hair growth: An uncontrolled pilot study
,”
BMC Res. Notes
7
,
103
(
2014
).
18.
A.
Munck
,
M. F.
Gavazzoni
, and
R. M.
Trueb
, “
Use of low-level laser therapy as monotherapy or concomitant therapy for male and female androgenetic alopecia
,”
Int. J. Trichol.
6
,
45
49
(
2014
).
19.
J. J.
Jimenez
,
T. C.
Wikramanayake
,
W.
Bergfeld
,
M.
Hordinsky
,
J. G.
Hickman
,
M. R.
Hamblin
, and
L. A.
Schachner
, “
Efficacy and safety of a low-level laser device in the treatment of male and female pattern hair loss: A multicenter, randomized, sham device-controlled, double-blind study
,”
Am. J. Clin. Dermatol.
15
,
115
127
(
2014
).
20.
S.
Friedman
and
P.
Schnoor
, “
Novel approach to treating androgenetic alopecia in females with photobiomodulation (low-level laser therapy)
,”
Dermatol. Surg.
43
,
856
867
(
2017
).
21.
Y.
Huang
,
F.
Zhuo
, and
L.
Li
, “
Enhancing hair growth in male androgenetic alopecia by a combination of fractional CO2 laser therapy and hair growth factors
,”
Lasers Med. Sci.
32
,
1711
1718
(
2017
).
22.
H.
Kim
,
J. W.
Choi
,
J. Y.
Kim
,
J. W.
Shin
,
S. J.
Lee
, and
C. H.
Huh
, “
Low-level light therapy for androgenetic alopecia: A 24-week, randomized, double-blind, sham device-controlled multicenter trial
,”
Dermatol. Surg.
39
,
1177
1183
(
2013
).
23.
R. J.
Lanzafame
,
R. R.
Blanche
,
A. B.
Bodian
,
R. P.
Chiacchierini
,
A.
Fernandez-Obregon
, and
E. R.
Kazmirek
, “
The growth of human scalp hair mediated by visible red light laser and LED sources in males
,”
Lasers Surg. Med.
45
,
487
495
(
2013
).
24.
R. J.
Lanzafame
,
R. R.
Blanche
,
R. P.
Chiacchierini
,
E. R.
Kazmirek
, and
J. A.
Sklar
, “
The growth of human scalp hair in females using visible red light laser and LED sources
,”
Lasers Surg. Med.
46
,
601
607
(
2014
).
25.
M.
Leavitt
,
G.
Charles
,
E.
Heyman
, and
D.
Michaels
, “
Hairmax LaserComb laser phototherapy device in the treatment of male androgenetic alopecia: A randomized, double-blind, sham device-controlled, multicentre trial
,”
Clin. Drug Invest.
29
,
283
292
(
2009
).
26.
B.
Barikbin
,
Z.
Khodamrdi
,
L.
Kholoosi
,
M. R.
Akhgri
,
M.
Haj Abbasi
,
M.
Hajabbasi
,
Z.
Razzaghi
, and
S.
Akbarpour
, “
Comparison of the effects of 665 nm low level diode laser hat versus and a combination of 665 nm and 808 nm low level diode laser scanner of hair growth in androgenic alopecia
,”
J. Cosmet. Laser Ther.
(to be published 2017).
27.
S. M.
Esmat
,
R. A.
Hegazy
,
H. I.
Gawdat
,
R. M.
Abdel Hay
,
R. S.
Allam
,
R.
El Naggar
, and
H.
Moneib
, “
Low level light-minoxidil 5% combination versus either therapeutic modality alone in management of female patterned hair loss: A randomized controlled study
,”
Lasers Surg. Med.
49
,
835
843
(
2017
).
28.
M. R.
Hamblin
, “
Photobiomodulation for the management of alopecia: Mechanisms of action, patient selection and perspectives
,”
Clin. Cosmet. Invest. Dermatol.
12
,
669
678
(
2019
).
29.
T.
Simsek
,
F.
Kocabas
,
J.
Zheng
,
R. J.
Deberardinis
,
A. I.
Mahmoud
,
E. N.
Olson
,
J. W.
Schneider
,
C. C.
Zhang
, and
H. A.
Sadek
, “
The distinct metabolic profile of hematopoietic stem cells reflects their location in a hypoxic niche
,”
Cell Stem Cell
7
,
380
390
(
2010
).
30.
J. C.
Tatmatsu-Rocha
,
C. R.
Tim
,
L.
Avo
,
R.
Bernardes-Filho
,
P.
Brassolatti
,
H. W.
Kido
,
M. R.
Hamblin
, and
N. A.
Parizotto
, “
Mitochondrial dynamics (fission and fusion) and collagen production in a rat model of diabetic wound healing treated by photobiomodulation: Comparison of 904 nm laser and 850 nm light-emitting diode (LED)
,”
J. Photochem. Photobiol. B Biol.
187
,
41
47
(
2018
).
31.
E.
Owusu-Ansah
and
U.
Banerjee
, “
Reactive oxygen species prime Drosophila haematopoietic progenitors for differentiation
,”
Nature
461
,
537
541
(
2009
).
32.
S. W.
Delaney
and
P.
Zhang
, “
Systematic review of low-level laser therapy for adult androgenic alopecia
,”
J. Cosmet. Laser Ther.
20
,
229
236
(
2018
).
33.
A.
Adil
and
M.
Godwin
, “
The effectiveness of treatments for androgenetic alopecia: A systematic review and meta-analysis
,”
J. Am. Acad. Dermatol.
77
,
136
141.e5
(
2017
).
You do not currently have access to this content.