{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T07:23:32Z","timestamp":1787210612307,"version":"build-2736575974"},"reference-count":25,"publisher":"Wiley","issue":"1","license":[{"start":{"date-parts":[[2026,8,19]],"date-time":"2026-08-19T00:00:00Z","timestamp":1787097600000},"content-version":"vor","delay-in-days":230,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"},{"start":{"date-parts":[[2026,1,1]],"date-time":"2026-01-01T00:00:00Z","timestamp":1767225600000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Pediatrics International"],"published-print":{"date-parts":[[2026,1]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>The COVID\u201019 pandemic has globally disrupted children's lifestyles, with emerging evidence indicating an increase in the prevalence of childhood obesity. However, longitudinal analyses focusing on age\u2010specific recovery patterns remain scarce, particularly in Asian populations.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      This study employed a retrospective longitudinal design utilizing mandatory school health examination data from Kurume City, Japan, collected from April 2018 to April 2021. The dataset comprised 4244 measurements from the pre\u2010pandemic, pandemic lockdown, and post\u2010pandemic periods. We examined BMI and BMI\u2010SDS trends using linear mixed\u2010effects models (\n                      <jats:italic>n<\/jats:italic>\n                      \u2009=\u2009711 children with complete three\u2010timepoint data) and individual BMI\u2010SDS trajectories using repeated measures ANOVA, stratified by gender and grade level.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Population\u2010level analysis using linear mixed\u2010effects models showed significant BMI increases during lockdown (boys: 16.60\u2009\u00b1\u20092.41 to 17.08\u2009\u00b1\u20092.78\u2009kg\/m\n                      <jats:sup>2<\/jats:sup>\n                      ,\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.04; girls: 16.39\u2009\u00b1\u20092.31 to 16.78\u2009\u00b1\u20092.53\u2009kg\/m\n                      <jats:sup>2<\/jats:sup>\n                      ,\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.03). Boys demonstrated significant BMI\u2010SDS increases from pre\u2010pandemic to pandemic (\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.019) and post\u2010pandemic (\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&lt;\u20090.001) periods, whereas girls showed no significant changes. Individual trajectory analysis revealed that children in Grade 2 (ages 7\u20138\u2009years) during lockdown demonstrated sustained BMI\u2010SDS increases up to 10\u2009months post\u2010pandemic in both genders (\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&lt;\u20090.01), with no significant sex differences (\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.807). In contrast, children in Grades 3\u20135 exhibited significant gender differences (\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&lt;\u20090.05), with boys showing greater vulnerability and more variable recovery patterns.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>The COVID\u201019 lockdown significantly affected childhood weight trajectories, with notable differences based on age and sex. Younger children exhibited sustained vulnerability, whereas older children demonstrated the capacity for recovery. These findings underscore the necessity of age\u2010specific intervention strategies during health emergencies.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1111\/ped.70536","type":"journal-article","created":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T06:24:32Z","timestamp":1787207072000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Age and Gender Differences in\n                    <scp>COVID<\/scp>\n                    \u201019 Lockdown Impacts on Childhood\n                    <scp>BMI<\/scp>\n                    : A Japanese Longitudinal Study"],"prefix":"10.1111","volume":"68","author":[{"given":"Rio","family":"Mukasa","sequence":"first","affiliation":[{"name":"Department of Pediatrics and Child Health Kurume University School of Medicine  Fukuoka Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4064-3102","authenticated-orcid":false,"given":"Shuichi","family":"Yatsuga","sequence":"additional","affiliation":[{"name":"Department of Pediatrics and Child Health Kurume University School of Medicine  Fukuoka Japan"},{"name":"Department of Medical Genetics Hakodate Goryoukaku Hospital  Hakodate Japan"},{"name":"Department of Pediatrics Fukuoka University School of Medicine  Fukuoka Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4610-5794","authenticated-orcid":false,"given":"Nobuoki","family":"Eshima","sequence":"additional","affiliation":[{"name":"Department of Pediatrics and Child Health Kurume University School of Medicine  Fukuoka Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Akiko","family":"Mukasa","sequence":"additional","affiliation":[{"name":"Faculty of Health Science, Department of Psychology Hiroshima International University  Hiroshima Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yushiro","family":"Yamashita","sequence":"additional","affiliation":[{"name":"Department of Pediatrics and Child Health Kurume University School of Medicine  Fukuoka Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,8,19]]},"reference":[{"key":"e_1_2_12_2_1","unstructured":"Ministry of Education Culture Sports Science and Technology \u201cSurvey on Implementation Status of Temporary School Closures in Response to COVID\u201019 \u201d(2020) Tokyo Japan: MEXT."},{"key":"e_1_2_12_3_1","doi-asserted-by":"publisher","DOI":"10.3390\/children8020135"},{"issue":"5","key":"e_1_2_12_4_1","doi-asserted-by":"crossref","DOI":"10.1542\/peds.2021-050123","article-title":"COVID\u201019 and Changes in Child Obesity","volume":"147","author":"Jenssen B. P.","year":"2021","journal-title":"Pediatrics"},{"issue":"37","key":"e_1_2_12_5_1","doi-asserted-by":"crossref","first-page":"1278","DOI":"10.15585\/mmwr.mm7037a3","article-title":"Longitudinal Trends in Body Mass Index Before and During the COVID\u201019 Pandemic Among Persons Aged 2\u201019\u2009Years\u2014United States, 2018\u20102020","volume":"70","author":"Lange S. J.","year":"2021","journal-title":"Morbidity and Mortality Weekly Report"},{"key":"e_1_2_12_6_1","doi-asserted-by":"publisher","DOI":"10.1001\/jama.2021.15036"},{"key":"e_1_2_12_7_1","doi-asserted-by":"publisher","DOI":"10.3390\/nu13103668"},{"key":"e_1_2_12_8_1","doi-asserted-by":"crossref","DOI":"10.5888\/pcd11.130355","article-title":"Accelerated Weight Gain Among Children During Summer Versus School Year and Related Racial\/Ethnic Disparities: A Systematic Review","volume":"11","author":"Franckle R.","year":"2014","journal-title":"Preventing Chronic Disease"},{"issue":"11","key":"e_1_2_12_9_1","doi-asserted-by":"crossref","first-page":"2296","DOI":"10.1002\/oby.21613","article-title":"From Kindergarten Through Second Grade, U.S. Children's Obesity Prevalence Grows Only During Summer Vacations","volume":"24","author":"Hippel P. 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