Table 5.
Mediational effects of longitudinal alcohol use trajectory classes on sexual-orientation differences in alcohol use disorders, stratified by gender: Growing Up Today Study, 2003–2010.
| Alcohol use disorder | |||||||
|---|---|---|---|---|---|---|---|
| Univariable | Multivariable model 1 | Multivariable model 2 | Proportion mediated | ||||
| % | P-value | RR (95% CI) | P-value | RR (95% CI) | P-value | % (P-value) | |
| Women | |||||||
| Sexual orientation | |||||||
| Completely heterosexual | 14.0 | <0.0001 | 1.00 (referent) | 1.00 (referent) | |||
| Mostly heterosexual | 30.8 | 2.17(1.91, 2.47) | <0.0001 | 1.78 (1.57, 2.01) | <0.0001 | 30.8 (<0.0001) | |
| Bisexual | 29.5 | 2.12 (1.59, 2.83) | <0.0001 | 1.85 (1.43, 2.38) | <0.0001 | 16.7 (0.0609) | |
| Lesbian | 29.3 | 2.00 (1.41, 2.83) | <0.0001 | 1.71 (1.23, 2.38) | 0.0013 | 31.1 (0.0180) | |
| Alcohol use trajectory classes | |||||||
| Non-drinkers | 1.3 | <.0001 | 1.00 (referent) | ||||
| Heavy drinkers | 40.3 | 29.82 (12.34, 72.08) | <0.0001 | ||||
| Moderate drinkers | 17.4 | 13.09 (5.40, 31.71) | <0.0001 | ||||
| Legal drinkers | 3.4 | 2.61 (0.98, 6.94) | 0.0538 | ||||
| Escalation- to moderately heavy drinkers | 16.3 | 11.79 (4.80, 28.94) | <0.0001 | ||||
| Light drinkers | 3.4 | 2.56 (0.99, 6.61) | 0.0519 | ||||
| Men | |||||||
| Sexual orientation | |||||||
| Completely heterosexual | 26.6 | 0.0015 | 1.00 (referent) | 1.00 (referent) | |||
| Mostly heterosexual | 36.7 | 1.34 (1.10, 1.64) | 0.0044 | 1.40 (1.18, 1.67) | 0.0002 | not mediated | |
| Bisexual | 38.9 | 1.54(0.84, 2.80) | 0.1604 | 1.67 (0.93, 3.01) | 0.0859 | not mediated | |
| Gay | 41.4 | 1.59 (1.25, 2.02) | 0.0001 | 1.72 (1.41, 2.10) | <0.0001 | not mediated | |
| Alcohol use trajectory classes | |||||||
| Non-drinkers | 1.3 | <0.0001 | 1.00 (referent) | ||||
| Heavy drinkers | 50.8 | 38.69 (12.69, 117.94) | <0.0001 | ||||
| Moderate drinkers | 19.2 | 13.72 (4.46, 42.21) | <0.0001 | ||||
| Legal drinkers | 7.6 | 5.60 (1.75, 17.89) | 0.0037 | ||||
| Escalation to moderately heavy drinkers | 29.6 | 22.39 (7.28, 68.90) | <0.0001 | ||||
Bold type indicates P < 0.05. Models were estimated with samples of 5122 women and 2510 men. Univariable P-values were derived using Rao–Scott χ2 tests for categorical variables and adjusted for sibling clusters. Multivariable models were adjusted for race/ethnicity, age, region, life-time college attendance (yes/no), number of surveys completed from 2003 to 2010 and mother’s household income. Models for women were also adjusted for life-time pregnancy (yes/no). RR = rate ratio; CI = confidence interval.