High levels of mental health problems among young people were reported during the COVID-19 pandemic, but studies of the post-pandemic period are scarce. We assessed mental health problems among Finnish youth before, during, and after the COVID-19 pandemic using nationwide population-based samples. Our aim was to examine in which direction the heightened levels of adolescent mental health problems have developed after the pandemic. In this national, repeated cross-sectional, population-based study in Finland, we recruited students at lower and upper secondary level (aged 13–20 years) who were taking part in the Finnish School Health Promotion (SHP) survey in 2015–23 (119 681–158 897 participants per round). The SHP is based on total sampling and conducted biennially between March and May. Self-reports covered the seven-item Generalized Anxiety Disorder Scale; the two-item Patient Health Questionnaire for depression; the Mini Social Phobia Inventory for social anxiety; the Short Warwick–Edinburgh Mental Wellbeing Scale for mental wellbeing; loneliness; the Sick, Control, One Stone, Fat, Food measure for disordered eating; and suicidality (suicidal ideation, deliberate self-harm, and suicide attempts). Scales were dichotomised using validated cutoffs. Presence of any and comorbid mental health problems was assessed. Logistic (for dichotomised outcomes) and linear (for Short Warwick–Edinburgh Mental Wellbeing Scale) mixed effects models were used to analyse the effect of survey year on mental health, controlling for sociodemographic background factors and stratified by gender and school level. Cisgender and transgender youth were compared. Between 2015 and 2023, the SHP study recruited 722 488 students (371 634 [51·6%] girls and 348 857 [48·4%] boys) with a mean age of 15·8 years (SD 1·3) who were either in the eighth and ninth grades of comprehensive school or the first and second years of general and vocational upper secondary schools in Finland. The proportion of participants with generalised anxiety, depression, and social anxiety symptoms above the cutoff increased from pre-COVID-19 levels to 2021 and remained at these higher levels in 2023 among all study groups. Among girls in lower secondary education, prevalence of generalised anxiety, depression, and social anxiety symptoms increased from 2021 to 2023, as did social anxiety among girls in upper secondary education. Among boys, the proportion with social anxiety symptoms decreased between 2021 and 2023. Mental wellbeing scores decreased in all groups between 2021 and 2023, and disordered eating increased in girls, and in boys in lower secondary education. Suicidality increased in girls but not in boys. Loneliness was the only measure to show improvement in all groups from 2021 to 2023. In 2023, 55 895 (72·6%) of 76 994 girls and 22 718 (32·8%) of 69 205 boys reported at least one mental health problem, and 37 250 (48·4%) girls and 9442 (13·6%) boys reported comorbid mental health problems. Among both transfeminine and transmasculine youth, the prevalence of generalised anxiety and depression symptoms decreased from 2021 to 2023, but compared with cisgender youth, the proportions were significantly higher throughout. The effects of the COVID-19 pandemic on youth mental health could be long lasting. In this study, the substantial change for the better among transgender youth was a positive exception. Providing adequate support and treatment for young people with poor mental health is essential, but solutions to the mental health crisis need to address a wider societal perspective and should be developed in partnership with young people. NordForsk, Research Council of Finland. For the Finnish and Swedish translations of the abstract see Supplementary Materials section.

中文翻译：

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COVID-19 大流行后芬兰青年的心理健康状况：一项基于人群的重复、横断面研究


据报道，在 COVID-19 大流行期间，年轻人存在大量心理健康问题，但对大流行后时期的研究却很少。我们使用基于全国人口的样本，评估了 COVID-19 大流行之前、期间和之后芬兰青年的心理健康问题。我们的目的是研究大流行后青少年心理健康问题的严重程度向哪个方向发展。在芬兰这项以人口为基础的全国性重复横断面研究中，我们招募了参加 2015-23 年芬兰学校健康促进 (SHP) 调查的初中和高中学生（13-20 岁） （每轮 119 681–158 897 名参与者）。 SHP 基于总体抽样，每两年在 3 月至 5 月期间进行一次。自我报告涵盖了七项广泛性焦虑症量表；抑郁症患者健康问卷的两项；针对社交焦虑的迷你社交恐惧症调查表；用于心理健康的简短沃里克-爱丁堡心理健康量表；孤独；针对饮食失调的疾病、控制、一石、脂肪、食物措施；自杀倾向（自杀意念、故意自残和自杀未遂）。使用经过验证的截止值对量表进行二分。评估是否存在任何合并症心理健康问题。使用逻辑（对于二分结果）和线性（对于短沃里克-爱丁堡心理健康量表）混合效应模型来分析调查年份对心理健康的影响，控制社会人口背景因素并按性别和学校水平分层。对顺性别和跨性别青年进行了比较。 2015 年至 2023 年间，SHP 研究招募了 722 488 名学生（371 634 [51·6%] 女生和 348 857 [48·4%] 男生），平均年龄为 15·8 岁 (SD 1·3)无论是芬兰综合学校的八年级和九年级，还是普通高中和职业高中的一年级和二年级。在所有研究组中，患有广泛性焦虑、抑郁和社交焦虑症状高于截止值的参与者比例从 COVID-19 之前的水平增加到 2021 年，并在 2023 年保持在较高水平。 2021 年至 2023 年，初中女生中广泛性焦虑、抑郁和社交焦虑症状的患病率有所增加，高中女生中的社交焦虑也是如此。 2021 年至 2023 年间，男孩中出现社交焦虑症状的比例有所下降。2021 年至 2023 年间，所有群体的心理健康得分均下降，初中教育中女孩和男孩的饮食失调情况有所增加。女孩的自杀率有所增加，但男孩的自杀率没有增加。从 2021 年到 2023 年，孤独感是显示所有群体有所改善的唯一衡量标准。2023 年，76 994 名女孩中的 55 895 名 (72·6%) 和 69 205 名男孩中的 22 718 名 (32·8%) 报告了至少一种心理健康状况37 250 (48·4%) 名女孩和 9442 (13·6%) 男孩报告了共病心理健康问题。在跨性别青少年和跨性别青少年中，2021年至2023年期间，广泛性焦虑和抑郁症状的患病率均有所下降，但与顺性别青少年相比，这一比例始终显着较高。 COVID-19 大流行对青少年心理健康的影响可能是长期持续的。在这项研究中，跨性别青年的显着好转是一个积极的例外。 为心理健康状况不佳的年轻人提供充分的支持和治疗至关重要，但心理健康危机的解决方案需要考虑更广泛的社会视角，并应与年轻人合作​​制定。 NordForsk，芬兰研究委员会。有关摘要的芬兰语和瑞典语翻译，请参阅补充材料部分。