Table 1.
Demographic characteristics of the sample
| BPD patients (n = 59) |
Well BPD relatives (n = 51) |
Controls (n = 198) |
Statistic (df) | p-value | |
|---|---|---|---|---|---|
| Age, years | 42.34 (11.7)a | 42.79 (11.9)b | 37.22 (12.1) | F(2,165) = 5.42 | 0.01 |
| Age range, years | 22–61 | 21–61 | 18–60 | ||
| Female sex, n (%) | 39 (66.1) | 23 (47.9)b | 136 (69.4) | F(2,165) = 3.61 | 0.03 |
| Education, years | 14.27 (3.2) | 15.13 (3.0) | 14.82 (2.4) | F(4,164) = 1.06 | 0.35 |
| Parental SES | 2.64 (1.2)c | 2.28 (0.9)b | 2.79 (0.9) | F(4,155) = 6.45 | 0.04 |
| Age of onset, years | 21.96 (6.3) | n/a | n/a | – | – |
| Duration of illness, years | 20.98 (10.9) | n/a | n/a | – | – |
| No. of hospitalizations | 4.81 (4.8) | n/a | n/a | ||
| Lifetime DSM diagnosis of substance abuse or dependence |
(A) dependence = 4 (A)/(S) abuse = 4 (S) abuse = 1 |
(A) dependence = 2 (A)/(S) dependence = 1 |
(A) abuse = 4 (A)/(S) dependence = 1 (A)/(S) abuse = 1 (S) abuse = 3 |
– | – |
| Current smoker, n (%) | 20 (34.5)a | 9 (19.1) | 36 (18.4) | F(4,164) = 4.28 | < 0.01 |
| No. cigarettes/day | 19.6 (12.2)a | 8.89 (4.8) | 9.75 (5.2) | F(4,49) = 3.90 | < 0.01 |
Data are presented as mean (SD) unless otherwise indicated. BPD = bipolar disorder; SES = socioeconomic status (A) = alcohol; (S) = substance.
a
Significant difference between patients and controls (p < 0.05).
b
Significant difference between relatives and controls (p < 0.05).
c
Significant difference between relatives and patients (p < 0.05).