The Effect of Laser Therapy for Stroke Patients : A Systematic Review and Meta-analysis

Da-young An; Seung-ho Sun; An, Da-young; Sun, Seung-ho

doi:10.13048/jkm.24003

JKM > Volume 45(1); 2024 > Article

An and Sun: The Effect of Laser Therapy for Stroke Patients : A Systematic Review and Meta-analysis

Original Article

The Journal of Korean Medicine 2024; 45(1): 44-63.

Published online: March 1, 2024

DOI: https://doi.org/10.13048/jkm.24003

The Effect of Laser Therapy for Stroke Patients : A Systematic Review and Meta-analysis

Da-young An¹

, Seung-ho Sun¹^{, *}

¹Department of Internal Korean Medicine, College of Korean Medicine, Sangji University

Correspondence to: Seung-ho Sun, Department of Internal Korean Medicine, College of Korean Medicine, Sangji University, Tel: +82-33-741-9202, Fax: +82-33-732-2124, E-mail: sunguy2001@hanmail.net

Received November 17, 2023 Revised February 9, 2024 Accepted February 16, 2024

Abstract

Objectives

This study is purposed to investigate the effect and safety of laser therapy for stroke patients by systematic review and meta-analysis of the randomized controlled trials (RCTs).

Methods

RCTs on the treatment of laser therapy for stroke patients were selected among the literature published from January 2000 to June 2022 in twelve domestic and foreign databases. The quality of the literature was evaluated using the Cochrane’s Risk of Bias tool and RevMan 5.4 was used for the synthesis of results.

Results

Total 2,598 patients with stroke were finally selected from 18 RCTs. Meta-analysis showed that laser therapy was effective in significantly improving activities of daily living (MBI), motor function (effective rate), upper motor function (FMA-UE), shoulder pain related factors (CGRP, ET-1, BK). Overall, the risk of bias was uncertain or low in the quality assessment of the literature.

Conclusions

Although it is unclear that laser therapy is more effective than sham laser, laser therapy might be more effective in improving symptoms than conventional rehabilitation alone. Furthermore, no serious adverse events were founded in laser therapy studies. However, the quality of the selected literature was generally low. Therefore, further studies with high methodological quality on laser therapy for stroke patients would be required in the future.

Keywords: Stoke, Systematic review, Meta-analysis, laser therapy, laser acupuncture

Fig. 1

PRISMA flow chart of study selection for Literature Reviews.

RISS: Research Information Sharing Service, NDSL: National Digital, Science Library, OASIS: Oriental Medicine Advanced Searching, Integrated System, CNKI: China National Knowledge Infrastructure.

Fig. 2

Results of meta-analysis for 0–2 score ratio of mRS (Laser therapy vs. Sham). mRS : modified Rankin Scale.

Fig. 3

Results of meta-analysis for MBI score (Laser therapy + Rehab vs. Rehab). MBI: Modified Bathel Index, Rehab: rehabilitation therapy.

Fig. 4

Results of meta-analysis for total effective rate (Laser therapy + Rehab vs. Rehab). Rehab: rehabilitation therapy.

Fig. 5

Results of meta-analysis for FMA-UE (Laser therapy + Rehab vs. Rehab). FMA-UE : The Fugl-Meyer Assessment for upper extremity, Rehab: rehabilitation therapy.

Fig. 6

Results of meta-analysis for VAS (Laser therapy + Rehab vs. Rehab). VAS : visual analogue scale, Rehab: rehabilitation therapy.

Fig. 7

Results of meta-analysis for CGRP (Laser therapy + Rehab vs. Rehab). CGRP : calcitonin gene-related peptide, Rehab: rehabilitation therapy.

Fig. 8

Results of meta-analysis for ET-1 (Laser therapy + Rehab vs. Rehab). ET-1 : endothelin 1, Rehab: rehabilitation therapy.

Fig. 9

Results of meta-analysis for BK (Laser therapy + Rehab vs. Rehab). BK : bradykinin, Rehab: rehabilitation therapy.

Fig. 10

Risk of bias graph.

Fig. 11

Risk of bias summary.

+ : Low risk of bias, - : High risk of bias, ? : Unclear risk of bias.

Table 1

Summary of the Randomized Controlled Trials of Laser Therapy for Stroke

Authors (year)	Study design	Sample size (intervention/control)	Stroke type (duration)	Gender (M/F) (A:intervention B:control)	Age (mean age)	Intervention Treatment			Control Treatment (time × sessions)	Main outcomes	Adverse event
Authors (year)	Study design	Sample size (intervention/control)	Stroke type (duration)	Gender (M/F) (A:intervention B:control)	Age (mean age)	(time × sessions)	Regimen	Applied points	Control Treatment (time × sessions)	Main outcomes	Adverse event
Lampl¹⁶⁾ (2007)	RCT	120 (79/41)	Cb-inf (<1 day)	A: 43/36 B: 26/15	NR (A: 70.2 B: 68.5)	Laser (2 min × NR, mean treatment time 18 hours)	808 nm 1 J/cm2	On the head	Sham (2 min × NR, mean treatment time 16 hours)	① NIHSS ② mRS ③ BI ④ GOS	None
Zivin¹⁷⁾ (2009)	RCT	660 (331/329-2 drop out)	Cb-inf (<1 day)	A: 183/148 B: 189/138	NR (A: 70.4±12.6 B: 70.0±11.9)	Laser (2 min × NR, NR)	808 nm NR	On the head	Sham (2 min × NR, NR)	① NIHSS ② mRS	None
Hacke¹⁸⁾ (2014)	RCT	630 (316/314)	Cb-inf (<1 day)	397/233	66±10 (A: 66±10 B: 65±11)	Laser (2 min × NR, NR)	808 nm NR	On the head	Sham (2 min × NR, NR)	① NIHSS ② mRS	5: Pain, skin laceration or erythema
Jiang¹⁹⁾ (2001)	RCT	60 (30/30)	Cb-inf Cb-hmrr (<5 days)	A: 15/15 B: 16/14	A: 44~80 (52.2) B: 45~79 (51.2)	Laser (60 min × 5~10 sessions) + conventional treatment (NR) :circulation of blood, etc.	633 nm NR	Intravascular : NR	Conventional treatment (NR) :circulation of blood, etc.	① total effective rate	NR
Luo²⁰⁾ (2001)	RCT	40 (20/20)	Cb-inf : 24 Cb-hmrr: 16 (1 day~3 years)	20/20	47~76 (NR)	Laser (10 min × 14 sessions) + conventional treatment(medication), Rehab(NR)	NR 70%	Stellate ganglion, LI11, TE5, LI4. GB20, GB30, BL54, SP6, SP9	Conventional treatment (medication), Rehab (NR)	① SSS (Unknown) ② MBI ③Effective rate	NR
Pan²¹⁾ (2003)	RCT	300 (150/150)	A: Cb-inf 126 Cb-hmrr: 24 B: Cb-inf: 124 Cb-hmrr: 26 (2~10days)	A: 72/78 B: 81/69	A: 40~75 (58.2±10.5) B: 47~69 (57.5±9.7)	Laser (30~60 min × 8~10 sessions) + conventional treatment (medication), Rehab (45 min × 5~6 days/week × NR)	633 nm 3~5 mW	Intravascular : Median Antebrachial vein	Conventional treatment (medication), Rehab (45 min × 5~6 days/week × NR)	① FMA ② BI	NR
Liu²²⁾ (2005)	RCT	82 (41/41)	Cb-inf (2~48hours)	A: 28/13 B: 27/14	A: 56~85 (63.4±9.4) B: 45~83 (64.2±8.7)	Laser (60 min × 20 sessions)	633 nm 1.5~2.0 mW	Intravascular : Median Antebrachial vein	Aspirin 300 mg/every day	① General effective rate ② Bood viscosity ③ Red cell hematocrit ④ RBC count ⑤ Cholesterol of blood lipid	None
KARABE GOVIĆ²³⁾ (2009)	RCT	70 (35/35)	NR (NR)	NR	NR (63.4±8.8)	Laser (NR)	830 nm 50 mW	On the painful points in the shoulder and area of swelling dorsum of the hand	Rehab(NR) : Electrotherapy	① VAS ② DASH ③ BI ④ FIM	NR
Feng²⁴⁾ (2013)	RCT	50 (25/25)	Cb-inf: 38 Cb-hmrr: 12 (NR)	A: 18/7 B: 18/7	33~71 (NR)	Laser (5~15 min × 14 sessions)	633 nm 10 mW	LI4, PC6, LI11, LI10, LI15, GB30, SP10, ST36, GB34, LR3	Conventional treatment; general Rehab (NR)	① Total effective rate	2: Neuralgia
Hu²⁵⁾ (2017)	RCT	63 (33/30)	A: Cb-inf: 23 Cb-hmrr: 10 B: Cb-inf: 22 Cb-hmrr: 8 (<3months)	A: 23/10 B: 21/9	A: 60~72 (65.89±15.12) B: 61~73 (66.34±15.32)	Laser (20 min × 24 sessions) + Rehab (30~40 min × 24 sessions) : Bobath training, balance training, and etc.	655 nm 4.2 mW	On the shoulder	Rehab (30~40 min × 24 sessions) : Bobath training, balance training, and etc.	① VAS ② FMA-UE	NR
Jan²⁶⁾ (2017)	RCT	38 (20/18)	NR (NR)	21/17	NR (52.92 ± 11.67)	Laser (10 min × 10 sessions)	905 nm 400 mW	On single shoulder joint	IFC (30 min × 10 sessions)	① VAS ② PSS ③ SPADI	NR
Yu²⁷⁾ (2018)	RCT	36 (19/17)	Cb-inf (<2weeks)	A: 12/7 B: 13/4	NR (A: 54.24±13.12 B: 57.28±9.87)	Laser (20 min × 30 sessions) + Rehab (45 min × 6 weeks): occupational therapy, balance training, and etc.	633 nm 120 mW	Head and GV20, LI10, TE5, LI4	Rehab (45 min × 6 weeks) :occupational therapy, balance training, and etc.	① FMA-UE ② MSS ③ MBI	NR
Sun²⁸⁾ (2018)	RCT	50 (25/25)	A: Cb-inf: 19 Cb-hmrr: 6 B: Cb-inf: 18 Cb-hmrr: 7 (<10days)	A: 18/7 B: 20/5	NR (A: 61.03±1.82 B: 60.64±2.51)	Laser (30 min × 48 sessions) + cognitive training (30 min × 48 sessions) and medication	650 nm 3.5~4.0 mW	In nasal cavity	Cognitive training (30 min × 48 sessions) and medication	① MMSE ② MoCA ③ LOTCA	NR
Zhang²⁹⁾ (2020)	RCT	60 (30/30)	NR (<12weeks)	A: 17/13 B: 15/15	NR (A: 67.3±4.2 B: 68.5±5.0)	Laser (5~10 min × 36 sessions) + Intelligent feedback training system (20 min × 36 sessions)	1064 nm 8~10W	On the shoulder (biceps, triceps, deltoid, rotator cuff)	Intelligent feedback training system (20 min × 36 sessions)	① PRI ② Swelling degree of the affected side ③ ROM ④ CRGP ⑤ ET-1 ⑥ BK	None
Zhao³⁰⁾ (2021)	RCT	101 (51/50)	A: Cb-inf: 26 Cb-hmrr: 25 B: Cb-inf: 24 Cb-hmrr: 26 (<4months)	A: 27/24 B: 27/23	A : 51~67 (58.12 ± 2.41) B: 49~65 (57.89±2.37)	Laser (10 min × 28 sessions) + Rehab (30 min × 28 sessions) : stretching, hot pack, ice pack, and etc.	1064 nm 8 W	On the shoulder (biceps, triceps, deltoid, rotator cuff)	Rehab (30 min × 28 sessions) : stretching, hot pack, ice pack, and etc.	① Effective rate ② EMG ③ CGRP ④ ET-1 ⑤ BK ⑥ FMA ⑦ MBI	NR
Qi³¹⁾ (2022)	RCT	114 (57/57)	A: Cb-inf: 38 Cb-hmrr: 19 B: Cb-inf: 35 Cb-hmrr: 22 (NR)	A: 30/27 B: 33/24	48~76 (64.75±6.65) A: 64.72±6.62 B: 64.79±6.69	Laser (20 min × 30 sessions) + Intelligent Rehabilitation robot (20~30 min × 30 sessions)	660 nm 30 mW	LU6, TE14, LI11, LI4, LI10, TE5, SP10, ST36, SP6, BL40, GB30, GB34, KI6	Intelligent Rehabilitation robot (20~30 min × 30 sessions)	① Velocity of PCA, MCA, ACA ② BBS ③ FMA-UE ④ FMA-LE	NR
He³²⁾ (2022)	RCT	80 (40/40)	Cb-inf Cb-hmrr (NR)	NR	NR	Laser (10 min × 14 sessions) + Pregabalin (bid × 14 sessions)	633 nm NR	On stellate ganglion	Pregabalin (bid × 14 sessions)	① VAS ② SF-36 ③ IL-6	3: Drowsiness, dizziness, drying mouth
Korkmaz³³⁾ (2022)	RCT	44 (22/22-3:dr op)	A: Cb-inf: 15 Cb-hmrr: 7 B: Cb-inf: 17 Cb-hmrr: 2 (>6months)	A: 10/12 B: 13/6	NR (A: 65.7±11.6 B: 60.4±12.1)	Laser (7.5 min × 9 sessions) + Rehab (NR × 15 sessions) : passive, active, stretching, strengthening, and mobilization exercises	1064 nm 8 W	On the shoulder (rotator cuff)	Rehab (NR × 15 sessions) : passive, active, stretching, strengthening, and mobilization exercises	① VAS ② ROM ③ BRS ④ MAS ⑤ FIM ⑥ SPADI ⑦ NHP ⑧ PTRCT	NR

RCT : randomized controlled trial, M: Male, F: Female, NR : not reported, Cb-inf : cerebral infarction, Cb-hrr : cerebral hemorrhage, NIHSS : National Institutes of Health Stroke Scale, mRS : modified Rankin Scale, BI : Barthel Index, GOS : Glasgow Outcome Scale, Rehab : rehabilitation therapy, MBI : Modified Barthel Index, FMA : The Fugl-Meyer Assessment, RBC : Red Blood Cell, VAS : visual analogue scale, DASH: The Disabilities of the Arm, Shoulder and Hand, FIM : functional independence measure, FMA-UE : The Fugl-Meyer Assessment for upper extremity, IFC : Interferential current treatment, PSS : Penn shoulders scale, SPADI : Shoulder Pain and Disability Index, MSS : motor status scale, MMSE : The Mini-Mental State Examination, MoCA : Montreal Cognitive Assessment, LOTCA : Loewenstein Occupational Therapy Cognitive Assessment, PRI : pain rating index, ROM : range of motion, CGRP : calcitonin gene-related peptide, ET-1 : endothelin 1, BK : bradykinin, EMG : electromyogram, PCA : posterior cerebral artery, MCA : middle cerebral artery, ACA : anterior cerebral artery, BBS : Berg Balance Scale, FMA-LE : The Fugl-Meyer Assessment for lower extremity, SF-36 : Short form 36 Questionnaire, IL-6 : Interleukin-6, BRS : Brunnstrom recovering staging, MAS : modified Ashworth scale, NHP : Nottingham health profile, PTRCT : partial thickness rotator cuff tear.

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