Sleep Disorders And Starting Time To School Impair Fine Motor Coordination In 5 Years Old Children

August 11, 2004

Moran CA,¹ Carvalho LC,¹ Prado LF,¹ Masuko AH,¹ Alencar KG,¹ Prado GF^2,1
(1) Neurology, Federal University of Sao Paulo, Sao Paulo, Sao Paulo, Brazil
(2) Internal Medicine, Federal University of Sao Paulo, Sao Paulo, Sao Paulo, Brazil

Introduction

Several studies have shown a probable negative influence of sleep disorders on cognition of school aged children, but few studies focus the possibility of motor abilities dysfunction in this age range. This study aims to verify if children with sleep disorders present dysfunction in fine motor coordination, and also to verify the influence of the starting time to school, as circadian rhythm could increase the effect of the sleep disorders on motor and cognitive functions.

Methods

We studied 272 five years old children from public schools of Sao Paulo City, SP, Brazil. The sleep disorders group (SDG) was identified by a sleep questionnaire (Bruni et al, 1996) adapted for Brazilian Portuguese language. Starting time to school enrolled were Morning (07:00AM finishing at 11:00AM); Intermediate (11:00AM finishing at 3:00PM); and Afternoon (3:00PM to 7:00PM). The SDG had 102 (58 boys) children with disorders of initiating and maintaining sleep, disorders of arousal, sleep breathing disorders, disorders of excessive somnolence, sleep hyperhydrosis, and sleep wake transition disorders. The control group (CG) had 170 children (86 boys).

To evaluate fine motor coordination, we request to the children to make a simple knot in a pedagogical shoe. We classify as a success in the test, if the children did the knot even with some difficulty. We consider fail if the children did not try the test or after some attempts did not make the knot. We compare the outcome success and fail for SDG and CG according to starting time to school (Morning, Intermediate and Afternoon). Qui-square and regression analysis were used to analyze the data.

Results

385 questionnaires had been distributed, 115 had not been used because there were children with visual, osteomuscular and/or neurological preexisting deficits or children out of the age range and children that had refused to participate or had not appeared in the date of the test application. Of 272 children, 144 (52.9%) were boys, 72 children studied in the morning, 104 studied in the afternoon and 96 children in the Intermediate. As a whole, there were no differences in the number of children that fail in the test according to the starting time to school. Boys and girls were not different as well, but when we added the starting time to school to the regression model we found that boys had more fail in the test (p< 0.05).

Conclusion

This study suggests that at least in some group of children, sleep disorders can interact with starting time to school allowing then to fail in some motor performance. We believe that five years old children studying in the afternoon failed in the test because they are deprived of some the still necessary afternoon sleep.