Meaningful word acquisition is associated with walking ability over 10 years in Rett syndrome

Tomoko Saikusa; Machiko Kawaguchi; Tetsuji Tanioka Tetsu T; Shin Nabatame Shin N; Satoru Takahashi; Kotaro Yuge; Shin-Ichiro Nagamitsu; Tomoyuki Takahashi; Yushiro Yamashita; Yasuyuki Kobayashi; Chisato Hirayama; Tatsuyuki Kakuma; Toyojiro Matsuishi; Masayuki Itoh

doi:10.1016/j.braindev.2020.06.012

Meaningful word acquisition is associated with walking ability over 10 years in Rett syndrome

Brain Dev. 2020 Nov;42(10):705-712. doi: 10.1016/j.braindev.2020.06.012. Epub 2020 Jul 17.

Authors

Affiliations

¹ Department of Pediatrics and Child Health, Kurume University School of Medicine, 67 Asahi-machi, Kurume, Fukuoka 830-0011, Japan.
² Biostatistics Center, Kurume University, 67 Asahi-machi, Kurume, Fukuoka 830-0011, Japan.
³ NPO Rett Syndrome Support Organization, 2-37-2 Tsudaminami-machi, Hirakata, Osaka, Japan.
⁴ Department of Pediatrics, Osaka University Graduate School of Medicine, Osaka 565-0871, Japan.
⁵ Department of Pediatrics, Asahikawa University, Asahikawa 078-8510, Japan.
⁶ Japan Rett Syndrome Association, 2-29-20-101 Kamiigusa, Suginami, Tokyo 167-002, Japan.
⁷ Sakuranbokai-Rett Syndrome, 63-2-101 Kawatsu, Iizuka, Fukuoka, Japan.
⁸ Research Center for Children, Research Center for Rett Syndrome, St. Mary's Hospital, Kurume, Fukuoka 830-8543, Japan. Electronic address: toyojiro@st-mary-med.or.jp.
⁹ Department of Mental Retardation and Birth Defect Research, National Center of Neurology and Psychiatry, 4-1-1 Ogawahigashi-machi, Kodaira, Tokyo 187-8502, Japan.

PMID: 32684376
DOI: 10.1016/j.braindev.2020.06.012

Abstract

Purpose: To investigate walking ability in Japanese patients with Rett syndrome (RTT).

Methods: Walking ability was assessed in 100 female Japanese patients with RTT using univariate and multivariate analysis in all age groups, and in patients over 10 years of age. We analyzed walking ability and confounding factors including prenatal-perinatal histories, developmental milestones, somatic and head growth, anthropometric data, body mass index, age of loss of purposeful hand use, age at onset of stereotypic hand movement, history of autistic behavior, age at regression, presence or absence of seizures, and the results of MECP2 genetic examination from the Japanese Rett syndrome database.

Results: Univariate analysis revealed that acquisition of walking in all age groups was significantly correlated with the acquisition of meaningful words, microcephaly, and crawling (P < 0.0001, P = 0.005, P < 0.0001, respectively). Univariate analysis revealed that walking ability over 10 years of age was significantly correlated with acquisition of meaningful words, microcephaly, and body mass index (P < 0,0001, P = 0.005, P = 0.0018, respectively). MECP2 mutations R306C, R133C, and R294X were significantly associated with different acquisition of crawling (P = 0.004) and walking (P = 0.01). Multivariate analysis revealed that only acquisition of meaningful words was significantly correlated with walking ability over 10 years of age. This trend excluded the genetic effects of R306C, R133C, and R294X.

Conclusions: Meaningful word acquisition was robustly associated with walking ability over 10 years. Prognosis of walking ability may be predicted by the acquisition of meaningful words. This information is potentially useful for early intervention and the planning of comprehensive treatment for young children with RTT.

Keywords: Ambulation; Japanese database; Methyl-CpG binding protein 2 mutation; Motor function; Multivariate analysis; Rett syndrome; Univariate analysis.

MeSH terms

Adolescent
Adult
Child
Child, Preschool
Female
Genotype
Humans
Infant
Japan
Methyl-CpG-Binding Protein 2 / genetics
Methyl-CpG-Binding Protein 2 / metabolism
Microcephaly
Mutation
Phenotype
Repressor Proteins / genetics
Rett Syndrome / genetics
Rett Syndrome / physiopathology
Rett Syndrome / psychology*
Severity of Illness Index
Speech / physiology*
Vocabulary
Walking / physiology*
Young Adult

Substances

MECP2 protein, human
Methyl-CpG-Binding Protein 2
Repressor Proteins