Split-hand index for amyotrophic lateral sclerosis diagnosis: A frequentist and Bayesian meta-analysis. (November 2022)

• Record Type: Journal Article
• Authors: Lu, Wei-Zhen; Lin, Hui-An; Hou, Sen-Kuang; Lee, Cheng-Fan; Bai, Chyi-Huey; Lin, Sheng-Feng
• Is Part Of: Clinical neurophysiology. Volume 143(2022)
• Page Start: 56
• Page End: 66
• Publication Date: 2022-11
• Subjects: Amyotrophic lateral sclerosis (ALS) -- Split-hand sign -- Split-hand index (SHI); ALS Amyotrophic lateral sclerosis -- ALSFRS-R the revised Amyotrophic Lateral Sclerosis Functional Rating Scale () score APB, abductor pollicis brevis -- AUC areas under the curves (AUC) -- CI confidence interval -- CMAP compound muscle action potential -- FDI first dorsal interosseous -- HPD highest posterior density -- I2 the Higgins index -- MCMC Markov Chain Monte Carlo -- MRC Medical Research Council -- PRISMA Preferred Reporting Items for Systematic Reviews and Meta-Analyses -- PROSPERO the International Prospective Register of Systematic Reviews database -- ROC receiver operating characteristic curves -- SBMA spinal and bulbar muscular atrophy -- SHI split-hand index -- SMD standardized mean differences -- TMS transcranial magnetic stimulation; Neurophysiology -- Periodicals; Electroencephalography -- Periodicals; Electromyography -- Periodicals; Neurology -- Periodicals; 612.8
• DOI: 10.1016/j.clinph.2022.08.020
• Languages: English
• ISSNs: 1388-2457

Abstract

Highlights: Split-hand index (SHI) should assist in identification of amyotrophic lateral sclerosis (ALS). Measurement of SHI should be considered for abductor pollicis brevis < 6.4 mV or first dorsal interosseous (FDI) < 8.4 mV. While ALS patients had decreased SHI, an SHI of < 7.4 can be used as a marker facilitating differential diagnosis of ALS. Abstract: Objective: Preferential wasting of the thenar muscles, the split-hand sign, may be used for early diagnosis of amyotrophic lateral sclerosis (ALS). Methods: Electronic databases were searched for studies assessing the split-hand index (SHI) and the compound muscle action potential (CMAP) amplitudes of abductor pollicis brevis (APB), first dorsal interosseous (FDI), and abductor digiti minimi (ADM). The SHI was obtained by multiplying CMAP amplitudes of APB and FDI and dividing the product by the CMAP amplitude of ADM. The Bayesian analysis was used for validation. Results: In total, 17 studies and 1635 patients were included. Our meta-analysis revealed that ALS patients had significantly decreased SHI (standardized mean difference [SMD], −1.60, P < 0.001), CMAP of the APB (SMD, −1.67, P < 0.001), FDI (SMD, −1.12, P < 0.001), and ADM (SMD, −1.09, P < 0.001). The binormal receiver operating characteristic curve analysis showed a threshold of < 7.4 for SHI, and cutoff values of < 6.4 mV for APB and < 8.4 mV for FDI, respectively. The Bayesian analysis validated decreased SHI in ALS patients (posterior mean difference of − 5.91). Conclusions: An SHI of < 7.4 can be used facilitating earlier diagnosis of ALS. Significance: SHI can be used as a standard neurophysiological biomarker for early diagnosis.