Background. Long-term use of lithium is the best-documented pharmacological prophylaxis of recurrences in bipolar disorder (BD). The beneﬁ cial effect of lithium prophylaxis is associated with a number of clinical and neurobiological factors. This paper attempts to evaluate the effectiveness of lithium prophylaxis in relation to schizotypal personality traits.
Methods. The study included 70 patients with bipolar disorder (49 women and 21 men), aged 31–82 years (59 ± 12 years) who have received lithium carbonate for a minimum of 5 years (5–37, average 15 years). The level of schizotypy and its various dimensions such as unusual experiences, cognitive disorganization, introversion and anhedonia, and impulsive nonconformity were assessed by the Oxford-Liverpool Inventory of Feelings and Experiences (O-LIFE) questionnaire. The results were correlated with the prophylactic efﬁ cacy of lithium assessed, using the so-called Alda scale, in the range of 0–10.
Results. In the whole group, the effectiveness of lithium on the Alda scale was 5,9 ± 2,7 and was similar in women (5,82 ± 2,8) and men (6,1 ± 2,6). The average value of each dimension was also similar in men and women and showed no correlation with age and with the length of lithium administration. Signiﬁ cant negative correlation between the effectiveness of lithium prophylaxis, and severity of cognitive disorganization dimension (r = -0,236 p = 0,025) was demonstrated, whereas no such correlation with other dimensions of schizotypy such as unusual experiences (r = -0,121), introversion and anhedonia (r = -0,166), impulsive nonconformity (r = -0,032) was found. Correlation between the effectiveness of lithium and impulsive nonconformity was positive in men (r = 0,214) and negative in women (r = -0,148) but not statistically signiﬁ cant.
Conclusions. Cognitive disorganization dimension measured by the scale of the O-LIFE is a negative factor associated with long-term efﬁ ciency of lithium in bipolar disorder.