Motor function in Rett syndrome: comparing clinical and parental assessments

To describe a new clinical tool, the Rett Syndrome Motor Evaluation Scale (RESMES) and to assess (loco-)motor function in people with Rett syndrome (RTT).

Formal assessment provided by physicians was followed by parents' direct observation at home using the RESMES. Sixty females (mean [SD] age 12y 5mo [8y 9mo], range 3-40y) with a clinical diagnosis and genetically determined RTT participated in the study. Spearman's/Pearson's coefficients assessed the correlation between the clinicians' and caregivers' evaluations, as well as the correlation of RESMES scores with other scales, namely the Pain Assessment in Advanced Dementia, the Rett Assessment Rating Scale, the Modified Ashworth Scale, and hand function (assessed with a scale of evaluation of purposeful hand function). Scores provided by parents and clinicians were tested statistically by Mann-Whitney U test.

Approximately 88% of patients had moderate to severe RTT symptoms and, on average, moderate motor impairment based on the RESMES. RESMES total scores provided by clinicians and caregivers were highly correlated (r=0.91), as were the subscale scores. Postural transition was a critical area of the RESMES, where parents systematically provided lower scores than clinicians, indicating milder degrees of disability. Severity of scoliosis and mutation type emerged as significant predictors of motor function.

The RESMES characterized the (loco-)motor impairments of the patients with RTT well. It also showed a close correlation between the evaluations of clinicians and caregivers, with the possible exception of postural transition tasks, which should be carefully addressed in a clinical setting. The type of mutation and presence of scoliosis should be evaluated, as they predicted the ability to walk.

Caregivers at home can reliably assess motor function in Rett syndrome using the Rett Syndrome Motor Evaluation Scale (RESMES). RESMES scores provided by clinicians and parents were highly correlated. The severity of scoliosis and the genetic mutation predicted standing and walking abilities.