Table 1

Sample characteristics (n=360)

CharacteristicPercentage or mean
1.Working, homemaker, student or retired.
2.In a stable relationship.
3.Characterised by majority of episodes.
4.Depression (D) or mania (M) (hypomania in type II) before a euthymic interval (I), followed by mania or depression in a majority of cycles before lithium; rapid cycling (RC): ≥ four episodes in any year before lithium maintenance.
Demographic factors (% of cases)
Women 64.7
Educated > 8 years 39.4
Employed1 81.7
Married2 46.4
Family history (% of cases)
All mood disorders 56.1
Bipolar 29.4
Unipolar 29.7
Suicide 1.82
Suicidal acts (% of cases) 18.3
Onset episode (% of cases)
Depressive 63.6
Manic 36.4
Diagnostic types (% of all cases)
Bipolar I3 60.6
typical 28.9
psychotic 27.8
mixed 3.89
Bipolar II 39.4
Course (% of cases)4
M-D-I 30.5
D-M-I 15.3
RC 14.7
Continuous non-RC 14.2
Erratic 25.3
Onset and treatment latency, years (mean (s.d.))
Onset age 29.2 (12.0)
Age at lithium start 37.4 (14.2)
Latency: onset to lithium 8.30 (8.23)
Lithium maintenance (mean (s.d.))
Duration of treatment (years) 6.00 (5.03)
Serum lithium concentrations (mmol/l) 0.615 (0.137)