TABLE 2.

Covariates and Adjusted Heritability Estimates for Blood Lipid Traits

Polygenic Model	TC	LDL-C	HDL-C	TG	LDL-C/HDL-C
Covariate screened, P value
Sex	0.74	0.15	9.99×10−15	7.96×10−6	2.91×10−8
Age	6.99×10−13	3.45×10−8	0.55	6.62×10−12	2.85×10−5
Age2	6.34×10	2.79×10	0.9	1.17×10	0.0007
Sex*age	0.93	0.98	0.51	0.71	0.93
Sex*age2	0.04	0.12	0.78	0.20	0.33
Physical activity	0.72	0.95	0.23	0.87	0.66
Alcohol drinking	0.13	0.27	0.01	0.82	0.8
Cigarette pack-years	0.34	0.15	0.06	0.46	0.11
Body mass index	0.01	0.0008	1.77×10−9	5.01×10−9	2.31×10−11
Waist-to-hip ratio	0.02	0.07	0.04	2.08×10−5	0.007
Proportion of variance due to covariates	0.15	0.11	0.15	0.20	0.15
Trait residual skewness	−0.29	−0.44	−0.19	0.52	−0.20
Trait residual kurtosis	0.65	0.79	0.36	0.63	0.39
Adjusted heritability
h2 ± SE	0.41 ± 0.07	0.44 ± 0.06	0.54 ± 0.06	0.56 ± 0.06	0.57 ± 0.06
P value	1.20×10−15	1.42×10−17	9.27×10−26	1.21×10−27	2.33×10−27

Traits were log-transformed.

h², heritability; SE, standard error.