Table 4

Association between anthropometric changes and incidence rate of diabetes by sex: results from Cox regression*

WomenMenRisk Diff.
HR †95% CIHR †95% CIRD †95%  CIP value
Per absolute changes
∆Weightn=12 330 (Power=0.99)n=7298 (Power=0.89)n=19 628 (Power=1.00)
 per SD gain1.131.08 to 1.191.201.14 to 1.270.07−0.02 to 0.140.32
∆BMIn=12 324 (Power=0.99)n=7292 (Power=0.89)n=19 616 (Power=1.00)
 per SD gain1.141.08 to 1.191.231.15 to 1.310.08−0.03 to 0.170.10
∆WCn=12 311 (Power=0.99)n=7283 (Power=0.89)n=19 594 (Power=1.00)
 per SD gain1.181.12 to 1.241.251.18 to 1.340.07−0.02 to 0.150.26
∆WHR ‡n=12 287 (Power=0.99)n=7226 (Power=0.88)n=19 513 (Power=1.00)
 per SD gain1.081.05 to 1.111.171.11 to 1.220.090.03 to 0.130.006
Per relative changes
∆Weight‡n=12 330 (Power=0.99)n=7298 (Power=0.89)n=19 628 (Power=1.00)
 per 5% gain1.141.08 to 1.191.231.17 to 1.320.090.01 to 0.180.08
∆BMIn=12 324 (Power=0.99)n=7292 (Power=0.89)n=19 616
 per 5% gain1.141.08 to 1.201.211.14 to 1.280.07−0.02 to 0.150.17
∆WCn=12 311 (Power=0.99)n=7283 (Power=0.89)n=19 594 (Power=1.00)
 per 5% gain1.201.14 to 1.271.281.19 to 1.370.08−0.02 to 0.160.26
∆WHR‡n=12 287 (Power=0.99)n=7226 (Power=0.88)n=19 513 (Power=1.00)
 per 5% gain1.091.06 to 1.131.191.13 to 1.270.100.03 to 0.170.009
By categories
∆Weightn=12 330 (Power=0.99)n=7298 (Power=0.89)n=19 628 (Power=1.00)
 >5% loss0.690.54 to 0.880.630.46 to 0.86−0.06−0.38 to 0.350.90
 ±5%Ref.Ref.Ref.Ref.Ref.Ref.-
 >5% gain1.341.09 to 1.641.541.25 to 1.910.20−0.13 to 0.540.50
∆BMIn=12 324 (Power=0.99)n=7292 (Power=0.89)n=19 616 (Power=1.00)
 >5% loss0.690.54 to 0.880.700.52 to 0.930.10−0.30 to 0.470.74
 ±5%Ref.Ref.Ref.Ref.Ref.Ref.-
 >5% gain1.301.07 to 1.601.581.29 to 1.950.28−0.08 to 0.610.18
∆WCn=12 311 (Power=0.99)n=7283 (Power=0.89)n=19 594 (Power=1.00)
 >5% loss0.670.52 to 0.870.520.39 to 0.71−0.15−0.47 to 0.150.24
 ±5%Ref.Ref.Ref.Ref.Ref.Ref.-
 >5% gain1.461.21 to 1.771.411.13 to 1.76−0.05−0.28 to 0.270.71
∆WHRn=12 287 (Power=0.99)n=7226 (Power=0.88)n=19 513 (Power=1.00)
 >5% loss0.720.54 to 0.960.530.40 to 0.71−0.18−0.50 to 0.090.20
 ±5%Ref.Ref.Ref.Ref.Ref.Ref.
 >5% gain1.501.22 to 1.841.441.13 to 1.83−0.06−0.31 to 0.290.74
  • *The study power was calculated based on the reported number of participants in each analyses to detect a HR of 1.1 or greater in Cox regression analyses, with the assumption that the overall event rate (diabetes) is 5.0 per 1000 person-year.

  • †HR and RD were estimated using the Cox regression with anthropometric changes from baseline to either 2004 or 2008 as time-varying exposure (independent) variable and incidence of diabetes as outcome (dependent) variable, after accounting for age, ethnicity, household income, initial anthropometrics, smoking status, physical activity, HEI 2005 Canada tertiles (low/medium/high), parental history of diabetes, and baseline comorbidities (0/1/≥2).

  • ‡The difference between men and women was statistically significant with p<0.01 in Wald’s test of the interaction of the association of anthropometric changes with sex in Cox regression models.

  • BMI, body mass index; HEI, Healthy Eating Index; RD, risk difference; WC, waist circumference; WHR, waist-hip-ratio.