Participant characteristics according to tri-allelic 5-HTTLPR genotype (5-HTTLPR/rs25531) and sex
| Characteristic* | S'S' homozygotes | L' allele carriers | t or χ2 | p value |
|---|---|---|---|---|
| Females, n | 865 | 326 | ||
| Age, yr, mean ± SD | 42.0 ± 11.7 | 42.3 ± 11.7 | 0.38 | 0.70 |
| BMI, kg/m2, mean ± SD | 21.7 ± 3.07 | 21.9 ± 3.35 | 0.95 | 0.34 |
| Current smoker, n (%) | 69 (8.0) | 28 (8.6) | 0.12 | 0.73 |
| Weekly regular exercise | — | — | 2.84 | 0.24 |
| Nil, n (%) | 552 (63.8) | 196 (60.1) | — | — |
| 1–2 times/wk, n (%) | 197 (22.8) | 74 (22.7) | — | — |
| ≥ 3 times/wk, n (%) | 116 (13.4) | 56 (17.2) | — | — |
| GAD patients, n | 295 | 126 | — | — |
| BAI score, mean ± SD | 10.5 ± 11.1 | 11.6 ± 11.5 | 1.14 | 0.16 |
| GAD diagnosis† | — | — | 0.31 | 0.58 |
| Current, n (%) | 264 (89.5) | 115 (91.3) | — | — |
| Remitted, n (%) | 31 (10.5) | 11 (8.7) | — | — |
| Depressive disorder, n (%)‡ | 66 (22.4) | 20 (15.9) | 2.30 | 0.13 |
| Other anxiety disorder, n (%)§ | 26 (8.8) | 10 (7.9) | 0.08 | 0.77 |
| Chronic medical condition, n (%)¶ | 61 (20.7) | 28 (22.2) | 0.81 | 0.37 |
| Psychotropic medication, n (%)** | 72 (24.4) | 22 (17.5) | 2.50 | 0.12 |
| Antidepressant, n (%) | 55 (18.6) | 19 (15.1) | 0.77 | 0.38 |
| Mood stabilizer, n (%) | 5 (1.7) | 0 (0) | 2.16 | 0.33†† |
| Antipsychotic, n (%) | 16 (5.4) | 5 (4.0) | 0.40 | 0.53 |
| Benzodiazepine, n (%) | 65 (22.0) | 21 (16.7) | 1.57 | 0.21 |
| Males, n | 770 | 275 | — | — |
| Age, yr, mean ± SD | 37.7 ± 11.1 | 36.8 ± 11.1 | 1.16 | 0.25 |
| BMI, kg/m2, mean ± SD | 24.1 ± 3.25 | 23.8 ± 2.95 | 1.13 | 0.26 |
| Current smoker, n (%) | 253 (32.9) | 81 (29.5) | 1.08 | 0.30 |
| Weekly regular exercise | — | — | 0.14 | 0.93 |
| Nil, n (%) | 376 (48.8) | 136 (49.5) | — | — |
| 1–2 times/wk, n (%) | 236 (30.6) | 81 (29.5) | — | — |
| ≥ 3 times/wk, n (%) | 158 (20.5) | 58 (21.1) | — | — |
| GAD patients, n | 232 | 83 | — | — |
| BAI score, mean ± SD | 8.72 ± 10.9 | 8.00 ± 10.8 | 0.98 | 0.33 |
| GAD diagnosis† | — | — | 6.17 | 0.013 |
| Current, n (%) | 211 (90.9) | 67 (80.7) | — | — |
| Remitted, n (%) | 21 (9.1) | 16 (19.3) | — | — |
| Depressive disorder, n (%)‡ | 28 (12.1) | 13 (15.7) | 0.70 | 0.40 |
| Other anxiety disorder, n (%)§ | 21 (9.1) | < 5 | 1.50 | 0.22 |
| Chronic medical condition, n (%)¶ | 40 (17.2) | 16 (19.3) | 1.73 | 0.68 |
| Psychotropic medication, n (%)** | 47 (20.3) | 20 (24.1) | 0.54 | 0.46 |
| Antidepressant, n (%) | 39 (16.8) | 16 (19.3) | 0.26 | 0.61 |
| Mood stabilizer, n (%) | 5 (2.2) | < 5 | 0.30 | 1.00†† |
| Antipsychotic, n (%) | 5 (2.2) | < 5 | 1.56 | 0.25†† |
| Benzodiazepine, n (%) | 43 (18.5) | 19 (22.9) | 0.73 | 0.39 |
BAI = Beck Anxiety Inventory; BMI = body mass index; GAD = generalized anxiety disorder; SD = standard deviation.
↵* Categorical data are reported as numbers (percentages); continuous data are presented as mean ± SD.
Populations of fewer than 5 people have been rounded to protect participant privacy.
↵† Current GAD = BAI > 7; remitted GAD = BAI ≤ 7.
↵‡ Depressive disorder: major depression, dysthymia or depressive disorder not otherwise specified.
↵§ Other anxiety disorder: phobic disorder, panic disorder or obsessive–compulsive disorder.
↵¶ Chronic medical condition: cardiovascular disease, asthma, liver disease, kidney disease, thyroid disease or cancer.
↵** Psychotropic medication: antidepressant, benzodiazepine, mood stabilizer or antipsychotic.
↵†† Fisher exact test.