Table 1.
Association between TTC12-rs10502172, CHRNA3-rs1051730, maternal smoking, socio-economic status, and gender with smoking behavior at 14 and 31 years. Analyses are computed by using multinomial logistic regression. Non-smokers are the reference category both at age 14 and 31 years. Effect sizes for each variable are adjusted for the effect of all other variables listed in the table and for principal components (PCs) to correct for population stratification. Genetic effect is estimated assuming an additive model of number of risk alleles for each locus.
| Smoking at 14 yrs |
Smoking at 31 yrs |
|||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Occasional-smokers (N=491) vs. non-smoker (N= 3,787) |
Regular-smokers (N= 279) vs. non-smokers (N= 3,787) |
Light-smokers (N=947) vs. non-smokers (N=2,589) |
Heavy-smokers (N=932) vs. non-smokers (N=2,589) |
|||||||||
| OR | (95% CI) | P Value | OR | (95% CI) | P Value | OR | (95% CI) | P Value | OR | (95% CI) | P Value | |
| TTC12-rs10502172[G] | 1.29 | (1.12–1.48) | <0.001 | 1.33 | (1.11–1.60) | 0.002 | 1.13 | (1.01–1.26) | 0.03 | 1.14 | (1.02–1.28) | 0.02 |
| CHRNA3-rs1051730[A] | 1.06 | (0.91–1.22) | 0.45 | 1.27 | (1.06–1.52) | 0.01 | 0.95 | (0.84–1.06) | 0.35 | 1.28 | (1.13–1.44) | <0.001 |
| Gender | ||||||||||||
| Female (N=2,476) | 1 | 1 | 1 | 1 | ||||||||
| Male (N=2,286) | 1.01 | (0.84–1.23) | 0.89 | 0.82 | (0.64–1.06) | 0.12 | 1.01 | (0.86–1.19) | 0.89 | 3.16 | (2.65–3.77) | <0.001 |
| Maternal smoking | ||||||||||||
| Non-smoker (N=4,000) | 1 | 1 | 1 | 1 | ||||||||
| Light-smokers (N=554) | 1.25 | (0.94–1.66) | 0.12 | 2.04 | (1.49–2.79) | <0.001 | 1.26 | (1.00–1.60) | 0.05 | 1.74 | (1.38–2.19) | <0.001 |
| Heavy-snokers (N=96) | 0.92 | (0.44–1.94) | 0.83 | 1.84 | (0.90–3.76) | 0.10 | 0.96 | (0.55–1.69) | 0.89 | 1.54 | (0.91–2.59) | 0.11 |
| Socio-economic statusa | ||||||||||||
| Professionals (N=1,341 at 14 yrs; N=1,098 at 31 yrs) | 1 | 1 | 1 | 1 | ||||||||
| Skilled-workers (N=1,573 at 14 yrs; N=1,481 at 31 yrs) | 1.17 | (0.92–1.49) | 0.20 | 1.57 | (1.12–2.19) | 0.01 | 1.56 | (1.26–1.94) | <0.001 | 1.59 | (1.24–2.04) | <0.001 |
| Unskilled-workers (N=987 at 14 yrs; N=1,215 at 31 yrs) | 1.13 | (0.86–1.49) | 0.38 | 2.31 | (1.63–3.27) | <0.001 | 1.89 | (1.51–2.38) | <0.001 | 3.04 | (2.41–3.82) | <0.001 |
| Farmers (N=674 at 14 yrs; N=164 at 31 yrs) | 0.89 | (0.64–1.22) | 0.46 | 0.88 | (0.54–1.44) | 0.62 | 0.86 | (0.53–1.40) | 0.55 | 0.75 | (0.44–1.29) | 0.29 |
| Others (N=747) | NA | NA | 1.68 | (1.30–2.17) | <0.001 | 2.31 | (1.76–3.02) | <0.001 | ||||
Abbreviations: OR, odds ratio; CI, confidence interval; NA: not applicable
Family socio-economic status measured at 14 was used to predict smoking at 14 years and socio-economic status measured at 31 was used to predict smoking at 31.