Influência da sazonalidade e fatores de risco associados ao desenvolvimento motor de lactentes nascidos a termo no município de Santa Maria – RS

Abstract

The appropriate motor development involves a number of factors linked to the environment in which the child lives. From the assumption of that, the issue in this study bases on a possible interference of seasonal variation that the infant population of Santa Maria’s town is exposed during the year, and its influence in motor development on the first year of life. Aim: To investigate the influence of seasonality on the motor development of infants born full-term and healthy, at 7 and 10 months old and risk factors associated. Methods: The study came from an umbrella-project that was approved by the Ethics in Research Committee (CEP/UFSM) under the number 1487549. The study included term infants born in target months, which had experienced motor development milestones for the 2nd and 3rd quarters during summer or winter. The data collection was made on medical files, interviewing the parents and application of Alberta Infant Motor Scale, which was applied by an examiner who was experienced and blind to the aims of the study, for further calculation of score. This result allowed the classification of children in the risk for motor delay group (score ≤ P25) and no risk for motor delay group (score > P25). Results: 174 children were evaluated, 97 (55.75%) at 7 months and 77 (44.25%) at 10 months. The assessed groups, after summer and after winter, presented themselves as homogeneous in sample characterization. There were no statistically significant difference regarding global motor development outcomes, although they have experienced very different thermal periods (24.75 ± 2.58° C in the summer and 13.96 4.18 ±° C in the winter; p = 0.000). The time of the crawling acquisition of the crawl was statistically significantly higher in the post-winter group (p=0,004) at 10 months. When classified by the risk of motor delay, it was observed at seven the prevalence of pregnancy planning (p = 0,015), longer time of exclusive breastfeeding (p = 0,004) and the total time of breastfeeding (p = 0.012), in the no risk group, giving advantage to this group seven months both in prevalence and multivariate regression model, in which it highlighted an advantage to those who were breastfed at any time. At ten months the risk group had a lower gestational age (p = 0,040), older mothers (p = 0,020), a higher number of children per woman (p = 0,002), higher prevalence of socio-economic benefit (p = 0,002) and children spend most of the time they are awake in limited locations (p = 0,000) and the variables inherent to the number of children, receiving socio-economic benefit and to the place where the infant spend most of their time, remained after multivariate regression. Conclusion: In the present study, the cold weather did not showed itself as a decisive factor for motor development. However, considering the multifactorial of this change, the cold can represent a limiting adjunct when associated with other causes for infants who experience the milestone acquisitions season of the year.