Abstract：
BACKGROUND: Sleep problems are frequent in children with attention-deficit/hyperactivity disorder (ADHD). Some authors have tried to characterize paediatric sleep habits in Portugal, but none has focused on preschool-age children nor attempted to establish their association with ADHD. We aimed to assess the prevalence of ADHD symptoms in preschool-age children and to study their association with sleep habits.
METHODS: We conducted a cross-sectional study. We distributed questionnaires to a random sample of caregivers of children enrolled in early childhood education centres in Porto. We collected data on sociodemographic characteristics, television watching and outdoor activities. We assessed ADHD symptoms and sleep habits with the Portuguese versions of the Conners\' Parents Rating Scale, Revised and the Children\'s Sleep Habits Questionnaire (CSHQ-PT), respectively.
RESULTS: The study included 381 preschoolers (50.90% male). We found high scores for ADHD symptoms in 13.10%, with a higher prevalence in girls (14.40% vs. 11.85%; P = 0.276). In the CSHQ-PT, 45.70% of participants had a mean total score greater than 48, which is the cut-off point applied in the screening of sleep disturbances in the Portuguese population. There was a significant association between high scores for ADHD symptoms and a lower maternal education level (P < 0.001), a shorter sleep duration (P = 0.049), and higher scores on parasomnias (P = 0.019) and sleep disordered breathing (P = 0.002) in CSHQ-PT subscales.
CONCLUSIONS: ADHD and sleep disorders are common in preschoolers, in Porto, and this study suggests some clinical correlations between them. Since these interactions are complex and far from being elucidated, further studies are paramount to provide guidance for prevention and managing strategies in younger children at risk for ADHD.
METHODS: We conducted a cross-sectional study. We distributed questionnaires to a random sample of caregivers of children enrolled in early childhood education centres in Porto. We collected data on sociodemographic characteristics, television watching and outdoor activities. We assessed ADHD symptoms and sleep habits with the Portuguese versions of the Conners\' Parents Rating Scale, Revised and the Children\'s Sleep Habits Questionnaire (CSHQ-PT), respectively.
RESULTS: The study included 381 preschoolers (50.90% male). We found high scores for ADHD symptoms in 13.10%, with a higher prevalence in girls (14.40% vs. 11.85%; P = 0.276). In the CSHQ-PT, 45.70% of participants had a mean total score greater than 48, which is the cut-off point applied in the screening of sleep disturbances in the Portuguese population. There was a significant association between high scores for ADHD symptoms and a lower maternal education level (P < 0.001), a shorter sleep duration (P = 0.049), and higher scores on parasomnias (P = 0.019) and sleep disordered breathing (P = 0.002) in CSHQ-PT subscales.
CONCLUSIONS: ADHD and sleep disorders are common in preschoolers, in Porto, and this study suggests some clinical correlations between them. Since these interactions are complex and far from being elucidated, further studies are paramount to provide guidance for prevention and managing strategies in younger children at risk for ADHD.
摘要：
背景：患有注意力缺陷/多动障碍（ADHD）的儿童经常出现睡眠问题。一些作者试图描述葡萄牙的儿科睡眠习惯，但是没有人关注学龄前儿童，也没有试图建立他们与ADHD的联系。我们旨在评估学龄前儿童ADHD症状的患病率，并研究其与睡眠习惯的关系。
方法：我们进行了一项横断面研究。我们向波尔图幼儿教育中心招募的儿童看护人的随机样本发放了问卷。我们收集了社会人口统计学特征的数据，看电视和户外活动。我们用葡萄牙语版本的Conners父母评定量表评估了ADHD症状和睡眠习惯，修订和儿童睡眠习惯问卷(CSHQ-PT)，分别。
结果：该研究包括381名学龄前儿童（50.90%为男性）。我们发现13.10%的ADHD症状得分很高，在女孩中的患病率较高(14.40%vs.11.85%；P=0.276）。在CSHQ-PT中，45.70％的参与者的平均总分大于48，这是葡萄牙人群睡眠障碍筛查的临界点。ADHD症状的高分与较低的母亲教育水平之间存在显着关联（P<0.001），睡眠时间较短（P=0.049），CSHQ-PT分量表的失眠症（P=0.019）和睡眠呼吸障碍（P=0.002）得分较高。
结论：多动症和睡眠障碍在学龄前儿童中很常见，在波尔图,这项研究表明了它们之间的一些临床相关性。由于这些相互作用是复杂的，远未被阐明，进一步的研究对于有ADHD风险的年幼儿童的预防和管理策略提供指导至关重要.
方法：我们进行了一项横断面研究。我们向波尔图幼儿教育中心招募的儿童看护人的随机样本发放了问卷。我们收集了社会人口统计学特征的数据，看电视和户外活动。我们用葡萄牙语版本的Conners父母评定量表评估了ADHD症状和睡眠习惯，修订和儿童睡眠习惯问卷(CSHQ-PT)，分别。
结果：该研究包括381名学龄前儿童（50.90%为男性）。我们发现13.10%的ADHD症状得分很高，在女孩中的患病率较高(14.40%vs.11.85%；P=0.276）。在CSHQ-PT中，45.70％的参与者的平均总分大于48，这是葡萄牙人群睡眠障碍筛查的临界点。ADHD症状的高分与较低的母亲教育水平之间存在显着关联（P<0.001），睡眠时间较短（P=0.049），CSHQ-PT分量表的失眠症（P=0.019）和睡眠呼吸障碍（P=0.002）得分较高。
结论：多动症和睡眠障碍在学龄前儿童中很常见，在波尔图,这项研究表明了它们之间的一些临床相关性。由于这些相互作用是复杂的，远未被阐明，进一步的研究对于有ADHD风险的年幼儿童的预防和管理策略提供指导至关重要.
