Table 6.
One-sample MR analyses of the effect of BMI (76 SNPs), WHR (39 SNPs) and WHRadjBMI (48 SNPs) on yearly hospital admission rate per year in UK Biobank participants of White British ancestry (N = 310,471). Rates and 95% confidence intervals (95% CI) are given. Estimates are provided per exposure SD (SDBMI=4.74 and SDWHR=0.090).
| Observational (adjusteda) | IV (adjustedb) | |
|---|---|---|
| Rated 95%CI | Rated 95%CI | |
| BMI (SD) | 1.077 (1.065–1.091) | 1.134 (1.015–1.267) |
| WHR (SD) | 1.162 (1.144–1.182) | 1.255 (0.997–1.580) |
| WHRadjBMI (SD) | 1.141 (1.120–1.163) | 1.216 (1.009–1.466) |
| WHR~BMI residuals (WHR SD)c | 1.123 (1.102–1.145) | 1.161 (0.968–1.391) |
BMI = body mass index, CI = confidence interval, IV = instrumental variable, SD = standard deviation, WHR = waist hip ratio, WHRadjBMI = waist hip ratio adjusted for BMI
a) Adjusted for sex (categorical), age at study entry, alcohol frequency (categorical, from on a daily basis to never), employment (categorical), qualifications (categorical), Townsend deprivation score (categorical in quintiles, where 1 is not deprived and 5 is very deprived), and days of exercise per week (categorical, from 1 to 7). The WHRadjBMI observational analyses also include BMI as a predictor.
b) Adjusted for sex, age at study entry, and 40 PCAs
c) Residuals from linear WHR on BMI regressions are used as an exposure with the WHRadjBMI SNPs as instruments
d) Estimates (with corresponding 95% CIs) represent the fold increase in yearly hospital admission rate per BMI SD (4.74 kg/m2) and per WHR SD (0.090). Estimates per BMI and WHR unit are given in Table S5.