Medication non-adherence for depressive and bipolar disorders range from 10 to 60 % (median 40 %). It has recently been concluded in a review 1 that it seems as attitudes and beliefs are at least as important as side-effects in predicting adherence in depressive and bipolar disorders 234. Beliefs and expectations has in several studies been found to be associated with non-adherence to lithium 156 and a recent study similarly concluded that attitudes and behaviours are better predictors of non-adherence to mood stabilizers than side effects of medication 7. Nevertheless, most of the studies have included a rather small number of patients 5891011 which might explain the very few attempts that have been made to correlate attitudes and beliefs with gender and age or with diagnostic subtypes (unipolar versus bipolar disorder) 12.

Demyttenaere et al 13 have recently developed a questionnaire (The Antidepressants Compliance Questionnaire (ADQC)) to measure attitudes and beliefs concerning depression and antidepressive treatment. Factor analysis identified four meaningful components 13 and the test-retest reliability of the ADQC was found acceptable 13. We have developed a questionnaire analogue to the ADQC to measure attitudes and beliefs concerning depressive and/or manic episodes and treatment with mood stabilizers, the Mood Stabilizer Compliance Questionnaire (MSCQ). We have thus replaced all the items concerning antidepressants with mood stabilizers and replaced items concerning depressive episodes with depressive and/or manic episodes. Apart from these adjustments no other changes have been made. Hence, the scoring of the items in the MSCQ is identical to the ADQC.

The objectives of the present study were (a) to characterise attitudes and beliefs on diagnosis and treatment with mood stabilizers by means of the MSQC among patients with severe depressive and bipolar disorders treated at their first contacts to hospital psychiatry and (b) to analyse the results in relation to socio-demographic and clinical variables. Thus, we have investigated the score on the MSQC in relation to age and gender and tested whether the score was different for patients with depressive disorder and patients with bipolar disorder and whether the score was related to the number of severe affective episodes patients had experienced.

Among the 1005 patients who were identified in the register with a diagnosis of depressive disorder or mania/bipolar disorder, 16 patients were excluded (7 due to unknown address, 6 as the patients did not understand Danish, 2 as the patients according to relatives were to demented and 1 as the patient has died). Among the remaining 989 patients who were potentially able to respond to the questionnaires, 493 patients fulfilled the questionnaires, corresponding to a response rate of 49.9 %. Among the 493 patients who fulfilled the questionnaires, 256 (51.9 %) responded that they previously or currently were in treatment with a mood stabilizer. Totally, 108 patients indicated that they currently were taking lithium, 10 patients were taking carbamazepine, 14 patient valproate and 35 patients were currently taking lamotrigene. Among these patients, 7 patients got combinations of various kinds of mood stabilizers. We did not ask for the type of the prior mood stabilizers, as such data may be inaccurate. As can be seen from Table 1, significantly more women (53.4 %) than men (45.2 %) responded to the overall questionnaires (p = 0.006). No significant age differences at first discharge were seen between the patients with depressive and those with bipolar disorder or between the numbers of admissions in responders versus non-responders to the questionnaire.

The responses to the 33 items of the MSQC are presented in Table 2 for the 256 patients who reported that they previously or currently were in treatment with a mood stabilizer. Mean (SD) values for each item are presented for patients with depressive and bipolar disorder, separately (also for comparison with future studies). Mean values were calculated according to the scoring system from 1 to 4 by Demyttenaere 13. The higher the score, the more positive the patients beliefs and attitudes toward compliance are. There were statistical differences in the scores between depressive and bipolar disorder in four items (items 4, 5, 18 and 24).

In general, the major proportion of patients agreed on the diagnosis and the choice and effect of pharmacological treatment and the majority felt content with their doctor and with information regarding diagnosis and treatment. Only minorities of patients had wrong ideas about dosing or the effect of mood stabilizers (You may take fewer tablets than prescribed on days when you feel better (8.1 %, item 8). If you forget to take the mood stabilizer on a certain day, it is better to take an additional dose the following day (10.6 %, item 23). You may take more tablets than prescribed on days when you feel more depressed (6.6 %, item 26). Skipping a day now and again prevents your body from becoming immune to the mood stabilizers (3.4 %, item 30)).

In contrast, a large proportion of the patients had non-correct views on the effect of mood stabilizers (Component2 (Preserved autonomy)). A total of 77.4 % of the sample of patients agreed on item 1 that as long as you are taking mood stabilizers you do not really know if they are actually necessary. Accordingly, 50.0 % agreed on item 3 that when you have taken mood stabilizers over a long period of time it is difficult to stop taking them and 37.3 % agreed on item 6 that when you take mood stabilizers you have less control over your thoughts and feelings. Further, 41.7 % agreed that mood stabilizers can alter your personality (item 9) and 49.8 % that your body can become addicted to mood stabilizers (item 13) and accordingly 36.1 % agreed that your body can become immune to mood stabilizers (item 24). A total of 61.0 % agreed that their depression and/or manic episodes are mainly due to factors associated with their personality (item 31).

Table 3 presents results from multiple regression analyses with component 1, 2, 3, 4 as outcome, respectively, and with inclusion of gender, age at first contact, number of admissions and type of disorder (depressive versus bipolar disorder) as predictive variables. As can be seen, age at first contact was negatively associated with all four components (higher age associated with lower score), however not significantly with component 4 (B = -0.003, p = 0.2). There were no significant associations between any component and gender, number of admissions or type of disorder (depressive disorder versus bipolar disorder). Including further a variable of educational level (dichotomised as primary school versus high school) did not change the results substantially, although age only was marginally associated with component 3 in this model (B = -0.009, p = 0.07). In these models, educational level was significantly and positively associated with component 3, only (B = 0.40, p = 0.002).

The above mentioned multiple regression models were repeated including further the variable describing the type of current doctor during outpatient treatment (general practitioner, private psychiatrist, community psychiatry doctor, hospital doctor, other doctor). There were no significant associations between any of the scores and type of doctor (p > 0.05).

The most consistent finding in the study was that among patients discharged from hospital with depressive or bipolar disorders, older patients consistently had a more negative view on the doctor-patient relationship (Component 1), a more negative view on mood stabilizers (Component 2) and more non-correct views on the effect of mood stabilizers (Component 3). Further, adjusting for differences in age, there were no differences between patients with depressive and patients with bipolar disorder in any component. There was no difference in the attitudes and beliefs according to the number of psychiatric hospitalisations or according to the type of the current doctor (general practitioner, private psychiatrist, community psychiatry doctor, hospital doctor, other doctor).

Although the major proportion of patients with depressive disorder and as well as with bipolar disorder agreed on the diagnosis and the choice and effect of pharmacological treatment and the majority felt content with their doctor and with information a large proportion of the patients had non-correct views on the effect of mood stabilizers (Component 3 and 4 (Preserved autonomy)). A total of 77.4 % of patients believed that as long as you are taking a mood stabilizer you do not really know if they are actually necessary and 36 to 50 % that you can become addicted or that mood stabilizers can alter your personality. It is most probably that such attitudes may result in reluctance to take mood stabilizers in the long run.

We included questions on reasons for discontinuing treatment but to few patients answered these questions. It is well known that direct questions on reasons for stopping treatment is flawed by a low response rate and by low validity of the answers. Thus, there is no single valid way to measure non-adherence 17. Questionnaires on attitudes and beliefs concerning illness and treatment such as the ADCQ and the MSCQ may be less provocative for patients and with a higher response rate.

We have previously reported on finding on attitudes and beliefs on antidepressants among the larger population of patients who received antidepressants 18. Thus, among the 493 patients who participated in the survey, 422 reported that they previously or currently were in treatment with an antidepressant (and these patients fulfilled the ADCQ, 18) and 256 that they previously or currently were in treatment with a mood stabilizer (and these patients fulfilled the MSCQ). The main proportion (88 %) of patients who previously or currently were in treatment with a mood stabilizer had at one point in time received an antidepressant and these patients fulfilled both questionnaires. The findings on attitudes and beliefs on mood stabilizers are surprisingly similar to the findings on attitudes and beliefs on antidepressants. It seems as patients who have negative attitudes toward mood stabilizers also have negative attitudes toward antidepressants as well, indicating a negative attitude toward medication in general.

It should be noted that patients who participated in the present study had had contact to the psychiatric health care system all over Denmark representing not only specialist university centres but also rural psychiatric hospitals, wards and centres.

Our findings are surprisingly similar to the results in a study by Schaub et al. who included a relatively small sample of patients (31 patients with depressive disorder and 74 with bipolar disorder) from a specialized lithium clinic 12. In this study, patient's knowledge on lithium treatment correlated negatively with age, whereas sex, diagnosis and duration of treatment were unrelated to knowledge. The MSQC has a broader scope than focusing on knowledge of medication only, and further age was consistent related to a more negative view on the diagnosis and on the doctor-patient relationship. The relation to age is further in accordance with results from studies of the general population 1920: the elderly had less correct knowledge on mental illnesses and depression and were more critical toward diagnosis and treatment. However, as stated by Schaub et al. 12 associations about treatment-related knowledge have not often been examined formally in psychiatric settings, nor in settings of somatic diseases 21. As mood stabilizers often are prescribed for many years and as elderly patients may present with cognitive dysfunction and somatic co-morbidity, lack of knowledge and a critical attitude toward diagnosis and treatment may add to deteriorate the prognosis even more. Such findings are consistent with the results from an ongoing pharmacoepidemiological study from our group showing that adherence to lithium is poor especially among patients aged 60 or more 22. All together these findings are consistent with the findings in some studies that older patients with bipolar disorder may present more often with mixed episodes and have a lower treatment response 23 and a higher risk of recurrence 24.

Although seldom investigated, prior studies have not found gender differences in knowledge of treatment 12. Similarly in the present study, no gender differences were found in attitudes toward diagnosis or treatment.

In the study by Schaub et al from a specialized lithium clinic, patients with depressive disorder had a lower knowledge about lithium treatment than patients with bipolar disorder 12. In the present study there was no difference among patients with these disorders. ICD-10 does not discriminate between bipolar disorder type 1 and 2 as both are categorised as bipolar disorder 15. We cannot exclude that some patients may have been misclassified as suffering from depressive disorder instead of bipolar disorder and that this may have diluted possible differences between the two illnesses.

We did not find any associations between scores on MSQC and the number of psychiatric hospitalisations. We are not aware of any other study besides the study by Schaub et al 12 that has investigated the relation between course of illness and attitudes and beliefs on illness and treatment. To avoid bias such studies have to be conducted prospectively as discussed in the following section on caveats of the present study.

The author(s) declare that they have no competing interests.