Setting | Sample size | Sample age range | Definition of obesity | Outcome measure and covariates | Results |
Perry DC et al.33 | |||||
Scotland | 597 017 children (distribution by sex and ethnic background unreported) | Age 5–6 to 18 years, diagnosis of SCFE or censor date (December 2016) | Age-specific and sex-specific BMI standardised to UK90 reference population Underweight <5th percentile, overweight ≥85th percentile, obese ≥95th percentile Mild/moderate obesity ≥95th–99th percentile, severe obesity ≥99th percentile | Diagnostic record of SCFE (ICD10 M93.0 or ICD9 732.2) in linked hospital admission records Covariates included in adjusted model: age, sex, quintile of SES deprivation | Adjusted IRR for SCFE was: 5.9 (3.9, 9.0) among those with severe obesity, 3.8 (2.6, 5.8) among those with mild/moderate obesity, 1.5 (0.9, 2.3) among those with overweight |
Ortiz-Pinto MA et al.34 | |||||
Madrid, Spain | 1884 children (50.8% male; distribution by ethnic background unreported) | Age 4 to 6 years | Age-specific and sex-specific BMI standardised to WHO 2006 reference tables Overweight z-BMI >+1 SD and ≤+2 SD, obese z-BMI >+2 SD Abdominal obesity based on waist-to-height ratio was defined as ≥90 th percentile Abdominal obesity based on waist circumference defined as ≥90 th percentile reference tables by Fernandez et al33 | Visits to doctor offices relating to musculoskeletal system coded using International Classification of Primary Care −2 Classification Covariates included in adjusted model: -sex, age, maternal educational level, familial purchasing power, time breastfeeding, perceived health status at age 4 years | Adjusted IRR for musculoskeletal complaints: 1.3 (1.0,1.6) among children with abdominal obesity based on waist-to-height ratio, compared with children with no abdominal obesity Adjusted IRR for musculoskeletal complaints among children with obesity: 1.3 (0.9,1.8) and with overweight (1.1; 0.9,1.4) based on z-BMI as indicator of obesity |
Palmer AJ et al.14 | |||||
Catalonia, Spain | 466,997 children (51.4% male; 89.0% Spanish, 11.0% other nationality) | Age 4 to 15 years, migration out of area, death or censor date (2016) | Age-specific and sex-specific BMI standardised to WHO 2007 guidance Underweight ≤2 SDs, normal weight −2 to +2, overweight >+2 and obesity >+3 | Lumbar spine pain (ICD-10: M54.1, M54.3, M54.4, M54.5) thoracic back pain (M54, M54.6, M54.8, M54.9) or cervical spine pain (M54.2) recorded in paediatric primary care clinics Covariates included in adjusted model: age, sex, SES, nationality | Cumulative incidence of any back pain by weight status: 8.8% (8.5, 9.1) normal weight, 10.1% (8.9, 11.4) overweight, 11.8% (9.4,14.2) obese Univariable HR for back pain: 1.2 (1.1, 1.3) for children with overweight and 1.3 (1.2, 1.5) for those with obesity compared with normal weight Adjusted HR for back pain: 1.2 (1.1, 1.3) for children with overweight and 1.3 (1.2, 1.5) for those with obesity compared with normal weight |
Lane JCE et al.15 | |||||
Catalonia, Spain | 466 997 children (51.4% male; 89.0% Spanish, 11.0% other nationality) | Age 4 to 15 years, migration out of area, death or censor date (2016) | Age-specific and sex-specific BMI standardised to WHO 2007 guidance Underweight ≤2 SDs, normal weight −2 to +2, overweight >+2 and obesity >+3 | Fractures recorded using Interntional Classification of Diseases-10 codes in primary care Covariates included in the adjusted model: sex, age, socioeconomic status, nationality | Cumulative incidence for fracture by weight status: 10.1% (9.8, 10.3) normal weight, 11.3% (10.2, 12.4) overweight, 13.1% (10.7, 15.4) obese Univariable HR for fractures: 1.1 (1.1,1 .2) for children with overweight and 1.3 (1.2, 1.4) for those with obesity compared with normal weight Adjusted HR for fractures: 1.1 (1.1, 1.2) among children with overweight and 1.2 (1.1, 1.3) among children with obesity compared with normal weight children |
BMI, body mass index; IRR, incidence rate ratios; SCFE, slipped capital femoral epiphysis.