Adaptation and validation of the Portuguese version of the Lithium Knowledge Test (LKT) of bipolar patients treated with lithium: cross-over study

Adriane R Rosa1,2, Ana Cristina Andreazza1,3, Fernando Kratz Gazalle1,4, Jose Sanchez-Moreno2, Aida Santin1, Airton Stein5, Helena MT Barros5, Eduard Vieta2, Flávio Kapczinski1
1Bipolar Disorders Program, Centro de Pesquisas, Clinic Hospital of Porto Alegre, Brazil and Post-Graduate Medical Science Program, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
2Bipolar Disorders Program, Clinical Institute of Neuroscience, Clinic Hospital of Barcelona, Barcelona, Spain
3Department of Biochemistry, Science Institute of Basic Disease, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
4Post-Graduate Psychiatry Program, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
5Pharmacology Departament, Federal Fundation University of Medical Sciences of Porto Alegre, Brazil

Tóm tắt

Adherence problems are a common feature among bipolar patients. A recent study showed that lithium knowledge was the main difference between adherent and non adherents bipolar patients. The Lithium Knowledge Test (LKT), a brief questionnaire, was developed as a means of identifying aspects of patients' practical and pharmacological knowledge which are important if therapy is to be safe and effective. The original English version is validated in psychiatric population, but a validated Portuguese one is not yet available. One hundred six patients selected were diagnosed with bipolar disorder (I or II) according to DSM-IV criteria and had to be on lithium treatment for at least one month. The LKT was administered on only one occasion. We analysed the internal consis tency, concurrent validity, sensitivity and specificity of the LKT for the detection of the knowledge about lithium treatment of bipolar patients. The internal consistency, evaluated by Cronbach's alpha was 0.596. The mean of total score LKT by bipolar patients was 9.0 (SD: 0.75) for men and 8.74 (SD: 0.44) for women. Concurrent validity based on plasma lithium concentration showed a significant correlation between the total LKT score and plasma lithium (r = 0,232; p = 0.020). The sensitivity was 84% and specificity was 81%. LKT is a rapid, reliable instrument which appears to be as effective as a lengthier standard interview with a lithium clinic doctor, and which has a high level of acceptability to lithium patients. We found that the psychometric assessment of the Portuguese version of LKT showed good internal consistency, sensitivity and specificity.

Tài liệu tham khảo

Dunner DL, Stallone F, Fieve RR: Lithium carbonate and affective disorders. V: A double-blind study of prophylaxis of depression in bipolar illness. Arch Gen Psychiatry. 1976, 33: 117-120. Tondo L, Baldessarini RJ, Floris G: Long-term clinical effectiveness of lithium maintenance treatment in types I and II bipolar disorders. Br J Psychiatry Suppl. 2001, 41: s184-s190. 10.1192/bjp.178.41.s184. Geddes JR, Burgess S, Hawton K, Jamison K, Goodwin GM: Long-term lithium therapy for bipolar disorder: systematic review and meta-analysis of randomized controlled trials. Am J Psychiatry. 2004, 161: 217-222. 10.1176/appi.ajp.161.2.217. Guscott R, Taylor L: Lithium prophylaxis in recurrent affective illness. Efficacy, effectiveness and efficiency. Br J Psychiatry. 1994, 164: 741-746. Schou M: The combat of non-compliance during prophylactic lithium treatment. Acta Psychiatr Scand. 1997, 95: 361-363. Kulhara P, Basu D, Mattoo SK, Sharan P, Chopra R: Lithium prophylaxis of recurrent bipolar affective disorder: long-term outcome and its psychosocial correlates. J Affect Disord. 1999, 54: 87-96. 10.1016/S0165-0327(98)00145-1. Schumann C, Lenz G, Berghofer A, Muller-Oerlinghausen B: Non-adherence with long-term prophylaxis: a 6-year naturalistic follow-up study of affectively ill patients. Psychiatry Res. 1999, 89: 247-257. 10.1016/S0165-1781(99)00108-0. Johnson RE, McFarland BH: Lithium use and discontinuation in a health maintenance organization. Am J Psychiatry. 1996, 153: 993-1000. Rosa AR, Marco M, Fachel JMG, Stein A, Barros HMT: Correlation between drug treatment adherence and lithium treatment attitudes and knowledge by bipolar patients. Prog Neuropsychopharmacol Biol Psychiatry. 2006, Colom F, Vieta E, Reinares M, Martinez-Aran A, Torrent C, Goikolea JM, Gasto C: Psychoeducation efficacy in bipolar disorders: beyond compliance enhancement. J Clin Psychiatry. 2003, 64: 1101-1105. Colom F, Vieta E, Sanchez-Moreno J, Martinez-Aran A, Reinares M, Goikolea JM, Scott J: Stabilizing the stabilizer: group psychoeducation enhances the stability of serum lithium levels. Bipolar Disord. 2005, 7 Suppl 5: 32-36. 10.1111/j.1399-5618.2005.00249.x. Molnar G, Feeney MG, Fava GA: Duration and symptoms of bipolar prodromes. Am J Psychiatry. 1988, 145: 1576-1578. Paykel ES: Psychotherapy, medication combinations, and compliance. J Clin Psychiatry. 1995, 56 Suppl 1: 24-30. Harvey NS, Peet M: Lithium maintenance: 2. Effects of personality and attitude on health information acquisition and compliance. Br J Psychiatry. 1991, 158: 200-204. Clarke DJ, Pickles KJ: Lithium treatment for people with learning disability: patients' and carers' knowledge of hazards and attitudes to treatment. J Intellect Disabil Res. 1994, 38 ( Pt 2): 187-194. Peet M, Harvey NS: Lithium maintenance: 1. A standard education programme for patients. Br J Psychiatry. 1991, 158: 197-200. Beaton DE, Bombardier C, Guillemin F, Ferraz MB: Guidelines for the process of cross-cultural adaptation of self-report measures. Spine. 2000, 25: 3186-3191. 10.1097/00007632-200012150-00014. Bullinger M, Alonso J, Apolone G, Leplege A, Sullivan M, Wood-Dauphinee S, Gandek B, Wagner A, Aaronson N, Bech P, Fukuhara S, Kaasa S, Ware JE: Translating health status questionnaires and evaluating their quality: the IQOLA Project approach. International Quality of Life Assessment. J Clin Epidemiol. 1998, 51: 913-923. 10.1016/S0895-4356(98)00082-1. Harvey NS: The development and descriptive use of the Lithium Attitudes Questionnaire. J Affect Disord. 1991, 22: 211-219. 10.1016/0165-0327(91)90067-3. Vieta E, Sanchez-Moreno J, Bulbena A, Chamorro L, Ramos JL, Artal J, Perez F, Oliveras MA, Valle J, Lahuerta.J., Angst J, for the EDHIPO (Hypomania Detection Study) group: Cross validation with the mood disorder questionnaire (MDQ) of an instrument for the detection of hypomania in Spanish: the 32 item hypomania symptom check list (HCL-32). J Affect Disord. 2006, Dharmendra MS, Eagles JM: Factors associated with patients' knowledge of and attitudes towards treatment with lithium. J Affect Disord. 2003, 75: 29-33. Kessing LV, Hansen HV, Bech P: Attitudes and beliefs among patients treated with mood stabilizers. Clin Pract Epidemol Ment Health. 2006, 2: 8-10.1186/1745-0179-2-8. Scott J, Pope M: Nonadherence with mood stabilizers: prevalence and predictors. J Clin Psychiatry. 2002, 63: 384-390. Colom F, Vieta E, Martinez-Aran A, Reinares M, Goikolea JM, Benabarre A, Torrent C, Comes M, Corbella B, Parramon G, Corominas J: A randomized trial on the efficacy of group psychoeducation in the prophylaxis of recurrences in bipolar patients whose disease is in remission. Arch Gen Psychiatry. 2003, 60: 402-407. 10.1001/archpsyc.60.4.402.