TABLE 3

Quantitative metabolic traits during an IVGTT in the population-based sample of 372 young healthy Danes stratified according to the MTNR1B rs10830963 genotype

rs10830963CCCGGGEffect per allele (95% CI)Padd
n(men/women)200 (104/96)146 (72/74)26 (8/18)
Age (years)25 ± 326 ± 426 ± 4
BMI (kg/m2)23.2 ± 3.523.9 ± 4.024.9 ± 3.80.7 (0.1 to 1.3)0.016
Fasting plasma glucose (mmol/l)4.92 ± 0.435.06 ± 0.475.17 ± 0.770.1 (0.07 to 0.2)0.00015
Fasting serum insulin (pmol/l)30 (23–45)30 (23–46)37 (29–51)−0.006 (−0.09 to 0.07)0.97
Acute serum insulin response 0–8 min (pmol/l × min)2,098 (1,297–3,018)1,642 (1,135–2,548)2,172 (1,387–2,621)−0.7 (−1.1 to −0.2)0.0022
Acute serum insulin response 0–10 min after tolbutamide injection (pmol/l × min)1,399 (765–2,248)1,376 (870–2,022)2,036 (1,357–2,588)0.1 (−0.3 to 0.5)0.60
Insulin sensitivity index (10−5× (min) × pmol/l)−1)13.5 (9.0–19.3)13.3 (9.0–20.3)11.1 (7.5–14.8)0.02 (−0.05 to 0.09)0.65
Disposition index28,760 (16,810–41,470)24,030 (16,480–33,730)23,900 (15,470–27,910)−1.3 (−2.3 to −0.2)0.021
  • Data are means ± SD (age, BMI, and plasma glucose) or medians (interquartile range). Values of fasting serum insulin, acute serum insulin response 0–8 min, acute serum insulin response 0–10 min after tolbutamide injection, insulin sensitivity index, and disposition index were transformed using cube root before statistical analysis, and their effect sizes are presented as the increase/decrease on a cubic scale. Calculated P values and effect sizes were adjusted for age, sex, and BMI (except for BMI) assuming an additive model. Acute serum insulin response 0–10 min after tolbutamide injection was in addition adjusted for plasma glucose values before the injection of tolbutamide. Acute serum insulin response 0–8 min, acute serum insulin response 0–10 min after tolbutamide injection, insulin sensitivity index, and disposition index are calculated as described elsewhere (17) and in the online appendix.