Accuracy of subjective and objective handwriting assessment for differentiating Parkinson’s disease from tremulous subjects without evidence of dopaminergic deficits (SWEDDs): an FP-CIT-validated study

• Published in: Journal of neurology Vol. 259; no. 11; pp. 2335 - 2340
• Main Authors: Bajaj, N. P. S., Wang, L., Gontu, V., Grosset, D. G., Bain, P. G.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01.11.2012; Springer; Springer Nature B.V
• Subjects: Accuracy; Adult; Aged; Aged, 80 and over; Basal ganglia; Biological and medical sciences; Central nervous system diseases; Classification; Degenerative and inherited degenerative diseases of the nervous system. Leukodystrophies. Prion diseases; Dopamine; Dopamine - deficiency; Female; Handwriting; Humans; Male; Medical sciences; Medicine; Medicine & Public Health; Middle Aged; Movement disorders; Neurodegenerative diseases; Neurology; Neuroradiology; Neurosciences; Original Communication; Parkinson Disease - classification; Parkinson Disease - diagnosis; Parkinson Disease - physiopathology; Parkinson's disease; Patients; Severity of Illness Index; tremor; Tremor (Muscular contraction); Tremor - classification; Tremor - diagnosis; United Kingdom > UK; Handwriting; Macrographia; SWEDDs (subjects without evidence of dopaminergic deficit); Micrographia; Parkinson’s disease; Human; Nervous system diseases; Accuracy; Parkinson's disease; MacrographiaMicrographia; Central nervous system disease; Parkinson disease; Degenerative disease; Cerebral disorder; Extrapyramidal syndrome
• ISSN: 0340-5354; 1432-1459; 1432-1459
• DOI: 10.1007/s00415-012-6495-5

Handwriting examinations are commonly performed in the analysis of tremor and Parkinson’s disease (PD). We analyzed the accuracy of subjective and objective assessment of handwriting samples for distinguishing 27 PD cases, 22 with tremulous PD, and five with akinetic-rigid PD, from 39 movement-disorder patients with normal presynaptic dopamine imaging (subjects without evidence of dopamine deficiency or SWEDDs; 31 with dystonic tremor (DT), six indeterminate tremor syndrome, one essential tremor, one vascular parkinsonism). All handwriting analysis was performed blind to clinical details. Subjective classification was made as: (1) micrographia, (2) normal, or (3) macrographia. In addition, a range of objective metrices were measured on standardized handwriting specimens. Subjective assessments found micrographia more frequently in PD than SWEDDs ( p  = 0.0352) and in akinetic-rigid than tremulous PD ( p  = 0.0259). Macrographia was predominantly seen in patients with dystonic tremor and not other diagnoses ( p  = 0.007). Micrographia had a mean sensitivity of 55 % and specificity of 84 % for distinguishing PD from SWEDDs and mean sensitivity of 90 % and specificity of 55 % for distinguishing akinetic-rigid PD from tremulous PD. Macrographia had a sensitivity of 26 % and specificity of 96 % for distinguishing DT from all other diagnoses. The best of the objective metrices increased sensitivity for the distinction of SWEDDs from PD with a reduction in specificity. We conclude that micrographia is more indicative of PD than SWEDDs and more characteristic of akinetic-rigid than tremulous PD. In addition, macrographia strongly suggests a diagnosis of dystonic tremor.