Study | No of subjects, year of birth | Measure of infant size | Definition of obesity | Analysis | Size of effect | Risk of bias |
---|---|---|---|---|---|---|

Mossberg (1989)^{26} Stockholm, Sweden | 27 (sex not reported), 1927-47 | Diagnosed as clinically obese by age 2 years | Weight for height SD scores at 40-50 years v reference population | Weight for height SD scores with obesity reported in infancy and at follow-up in adulthood | SD scores (SE of mean): 2.3 (0.31) on admission; 1.8 (0.46) in late childhood; 0.2 (0.28) in adulthood (40-50 years) | High |

Guo (1994)^{3} USA | 555 (50% male), 1929-60 | BMI at 75th centile v 50th centile | BMI >28 kg/m^{2} (men) or >26 kg/m^{2} (women) at 35 years | Logistic regression giving odds ratio for overweight in adulthood by higher BMI centile in infancy v lower one (50th, 75th centiles used) | Odds ratios (95% CI) at 1 year 1.48 (0.99 to 2.21) for males, 1.54 (1.01 to 2.35) for females; at 2 years 1.63 (1.04 to 2.54) for males, 1.51 (0.96 to 2.38) for females | Medium |

Eriksson (2003)7 Helsinki, Finland | 2135 male, 2380 female, 1933-44 | BMI at 6 months | Maximum lifetime risk of obesity defined as BMI≥30 kg/m2 at 60-70 years | Incidence (%) of adult obesity in each of four BMI categories at 6 months | Cumulative incidence (95% CI): males: 28.6 (24.1 to 33.1) in lowest 6 month group (<16.3 kg/m^{2}), 44.1 (40.0 to 48.5) in highest 6 month group (>18.0 kg/m2), P<0.0001 for trend; females: 27.5 (23.8 to 31.3) in lowest 6 month group (<16.3 kg/m2), 36.8 (32.0 to 41.7) in highest 6 month group (>18.0 kg/m^{2}), P=0.001 for trend | Medium |

Heald (1965)^{24} Washington DC; Massachusetts, USA | 158 cases, 94 controls (all female), 1945-50 | 1 year weight (lb) | Cases (clinically obese) and controls (not obese) at mean age 15 years | Mean values for infant size reported for cases and controls, with SDs and t tests for differences | Mean difference in 1 year weight (lb): cases-controls 1.446 (P=0.009) | High |

Charney (1976)16 Rochester, USA | 366 (sex not reported), 1945-55 | Infant obesity: weight centile >90% at 3 and 6 months | Weight≥20% above median for height and age at 20-30 years | Contingency tables of heavy, average, and light infants and underweight, normal, overweight, and obese adults, from which relative risks of adult obesity in “obese” v non-obese infants were derived | Relative risks: 1.63 (1.14 to 2.33) for unadjusted (n=366), 1.81 (0.96 to 3.44) for neither parent overweight (n=225), 3.37 (1.69 to 6.70) for at least one parent overweight (n=110), and 2.51 (2.25 to 2.80) for combined (n=335) | High |

Asher (1966)^{17} Birmingham, UK | 137 (sex not reported): 21 cases, 24 controls, 1950 | Infant obesity: weight >90th centile at 6 months; >97th centile at 6 months | Childhood obesity: weight >90th centile at 3-5 years; weight for height >97th centile at 5 years | Relative risk for child obesity in “obese” v non-obese infants | Relative risks: 9.33 (0.52 to 167) for weight >90th centile at 3-5 years; 6.56 (2.90 to 14.8) for weight for height >97th centile at 5 years | High |

Rolland-Cachera (1987)^{12} France | 164 (52% male), 1950 | Infant obesity: BMI >75th centile at 1 year | BMI >75th centile: >23.4 kg/m^{2} (men) or >22.3kg/m^{2} (women) at 21 years | Relative risk of obesity at 21 years in “obese” v non-obese infants | Relative risk (95% CI) 2.76 (1.32 to 5.77) | Medium |

Garn (1985)^{21} Tecumseh, USA | 135 (39% male), 1957-60 | Infant obesity at 1 or 2 years: triceps skinfold >85th centile for age/sex. Same definition for subscapular skinfold | Same definitions as for infancy at 21-22 years | Percentage of “obese” infants who remained obese 20 years later, with P value for deviation from chance figure of 15% (with binomial test) | Percentage of obese infant (triceps): 33.3% (P=0.21) at 1-21 years; 18.2% (P=0.77) at 2-22 years; percentage of obese infant (subscapular) 33.3% (P=0.21) at 1-21 years; 20.0% (P=0.66) at 2-22 years | Medium |

Johnston (1978)^{25} Philadelphia, USA | 798 (51% male), 1958-65 | Relative weight: weight for height≥1 SD at 1 year (high) v≤-1 at 1 year (low) | At 9-15 years: relative weight (predicted weight/actual weight)≥120%; triceps skinfold >90th centile for age, sex/race | Relative risk of obesity at ages 9-15 years; according to whether subjects had high or low relative weight or skinfold thickness at 1 year, stratified for sex | Relative risk (95% CI) for relative weight 3.75 (2.15 to 6.54) for males, 4.06 (2.52 to 6.53) for females; for triceps skinfold 2.97 (2.03 to 4.35) for males, 2.70 (1.74 to 4.17) for females | High |

Wilkinson (1977)^{23} Newcastle upon Tyne, UK | 48 cases; 48 controls (42% male), 1960-2 | Weight, at 6 and 12 months (obese >90th centile) | Obesity at 10 years, defined as weight for height >97th centile. Controls defined as weight for height 25th-75th centile | Odds ratio of obesity at 10 years according to weight at 6 and 12 months | Odds ratio (95% CI) of obesity at 10 years in children who had been obese at 6 or 12 months v non-obese infants: 6 month weight (n=48) 2.00 (0.88 to 4.56); 12 month weight (n=42) 1.62 (0.63 to 4.15) | Medium |

Whitaker (1997)^{11} Washington State, USA | 854 (36% male), 1965-70 | Infant obesity: BMI >85th centile (obese) or >95th (very obese) at 1-2 years | BMI≥27.8 kg/m2 (men) or≥27.3 kg/m^{2} (women) at 25 years | Logistic regression giving odds ratios for obesity in adulthood by whether “obese” or “very obese” in infancy v “not obese” | Odds ratio (unadjusted): 1.3 (0.7 to 2.5) for obese or very obese; 2.0 (0.7 to 5.7) for very obese (findings remained non-significant after adjustment for parental obesity) | Medium |

Poskitt (1977)^{18} Dudley, UK | 203 (49% male), 1968-70 | Percentage weight at age when height is at 50th centile, measured at around 5 months (obese >120%) | Same, at around 5 years | Relative risk of childhood obesity at 5 years of age for “obese” infants v non-obese infants | Relative risk (95% CI) 9.38 (1.64 to 53.6) | Medium |

Tienboon (2002)^{15} New South Wales, Australia | 83 (48% male), 1972 | BMI >1 SD from group mean for age at 1 year | BMI >1 SD from group mean at 15 years | Relative risk of obesity at 15 years for “obese” v non-obese infants | Relative risk (95% CI) 2.03 (0.47 to 8.82) | Medium |

He (1999)^{14} Gothenburg, Sweden | 3650 (51% male), 1972-5 | Infant obesity: BMI >18 kg/m2 (both sexes) at 1-2 years | BMI≥25kg/m^{2} (both sexes) at 18 years | Odds ratio of obesity at 18 years according to whether “obese” at 1 or 2 years | Odds ratio 995% CI) at 1 year: 1.62 (1.10 to 2.38) for males, 2.31 (1.57 to 3.41) for females, 1.93 (1.47 to 2.54) for both; at 2 years: 3.00 (2.03 to 4.43) for males, 2.90 (1.95 to 4.31) for females, 2.92 (2.22 to 3.86) for both | Medium |

Monteiro (2003)^{19} Pelotas, Brazil | 1041 (52% male), 1982 | Weight for height SD score at 2 years | BMI≥85th centile at 14-16 years | Odds ratio of overweight and obesity in adolescence associated with 1 unit change in infancy z scores for size | Unadjusted odds ratio (cut off + 1 SD at 2 years) 3.54 (2.53 to 4.96); odds ratio for 1 unit z score increase in weight for height SD 1.35 (1.53 to 1.73) adjusted for socioeconomic status, maternal size, and infant feeding | Low |

Stettler (2002)^{6} USA | 19 397 (50% male), 1985-90 | Infant size: weight at 1 year (g) | BMI >95th centile for age and sex at 7 years | Logistic regression giving odds ratio for risk of overweight at 7 years according to each unit (100g) increase in weight at 1 year | Odds ratios (95% CI):1.05 (1.04 to 1.05) unadjusted, 1.50 (1.38 to 1.63) adjusted for sex, birth weight, maternal BMI, and education | Medium |

Mei (2003)^{20} USA | 380 518 (51% male), 1986-90 | Weight for height≥95th centile at 0-11 months (1); weight for height≥95th centile at 12-23 months (2) | Weight for height≥95th centile at 24-35 months (3); weight for height≥95th centile at 36-47 months (4) | Relative risk of childhood obesity according to infant obesity category. No confidence intervals reported | Relative risk 3.3 for (1) and (3), 2.9 for (1) and (4), 6.4 for (2) and (3), 5.3 for (2) and (4) | Medium |

Reilly (2005)^{22} Avon, UK | 857 (sex not stated for infant growth analysis 51% in entire cohort), 1991-2 | Weight SD scores at 8 and 18 months | Obesity at age 7 years, defined as BMI≥95th centile relative to UK 1990 reference population | Logistic regression giving odds ratio of obesity at 7 years of age for children in highest quarter for weight SD score at 18 months v children in other quarters | Odds ratio (95% CI) for weight at 8 months: 3.03 (1.89 to 4.85) unadjusted, 3.13 (1.43 to 6.85) adjusted; weight at 18 months: 3.71 (2.29 to 6.00) unadjusted, 2.65 (1.25 to 5.59) adjusted (adjusted for birth weight, maternal smoking, parental obesity, hours of sleep at age 30 months, time spent watching television at 30 months, diet, maternal education, sex) | Low |