Clinical correlates of 9-hole peg test in a large population of people with multiple sclerosis

Objective: To assess the distribution of nine hole peg test (9-HPT) and its clinical correlates in a large sample of patients with multiple sclerosis (MS). Methods: Data was collected in a multi-centre, cross-sectional study involving 4 Italians MS centres. We collected demographic and clinical data of 363 patients (244 women, 199 men), including year of symptom onset, disease course, Expanded Disability Status Scale (EDSS). Results: A total of 206 (61.3%) patients scored >= 2 standard deviations (SDs) of normative values in both hands, while only 38 (11.3%) scored <1 SD from normative values at 9-HPT. We found ceiling and floor effects in mildly (EDSS < 3.0) and severely (EDSS > 6.0) impaired patients. Patients with a primary progressive disease course and those with a more severe disability level showed the large between-hand asymmetry. In multivariate models, predictors of unimanual and bimanual impairments were primary progressive course (odds ratio [OR] = 7.27, p = 0.001) and higher EDSS score (OR = 2.13 for each step, p < 0.001), respectively. Conclusion: We suggest that 9-HPT should be used with caution in patients with low or high disability levels. Between-hand asymmetry and stratification for age, disease course, and presence/absence of bilateral involvement should be taken into account for future study design.