Table 1.
Demographic and clinical variables of the study population
| Total | Lithium | Non-lithium | p value | |
|---|---|---|---|---|
| (n = 51) | (n = 23) | (n = 28) | ||
| Age (years), mean ± SD | 46.57 ± 9.21 | 48.48 ± 8.98 | 45 ± 9.26 | 0.18 |
| Gender (male/female) | 31/20 | 14/9 | 17/11 | 1 |
| Bipolar (I/II) | 33/18 | 12/11 | 21/7 | 0.14 |
| Age at onset (years), mean ± SD | 25.14 ± 11.24 | 24.43 ± 10.86 | 25.71 ± 11.71 | 0.69 |
| Number depressive episodes (mean ± SD) | 12.98 ± 15,79 | 10.55 ± 11,69 | 15.04 ± 18.56 | 0.31 |
| Number mania/hypomania (mean ± SD) | 8.87 ± 11.78 | 6.62 ± 9.11 | 10.76 ± 13.53 | 0.22 |
| Number of drugs (mean ± SD) | 2.41 ± 1.22 | 2.57 ± 1.20 | 2.29 ± 1.24 | 0.42 |
| Rapid cycling (no/yes) | 46/5 | 22/1 | 24/4 | 0.35 |
| HAMD (mean ± SD) | 6.39 ± 5.05 | 4.61 ± 3.13 | 7.86 ± 5.86 | 0.02 |
| BDI (mean ± SD) | 32 ± 8.84a | 29.39 ± 5.66 | 33.50 ± 10.93a | 0.09 |
| YMRS (mean ± SD) | 2.10 ± 2,56 | 2.04 ± 2,01 | 2.14 ± 2.98 | 0.88 |
aOne missing value. HAMD, Hamilton depression scale; BDI, Beck Depression Inventory; YMRS, Young Mania Rating Scale.