Martin Sköld1, Sindre Rolstad2, Erik Joas1, Mathias Kardell1, Erik Pålsson1, Guy M Goodwin3, Mikael Landén4,5. 1. Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Blå Stråket 15, 413 45, Gothenburg, Sweden. 2. Department of Psychology, Faculty of Social Science, University of Gothenburg, Gothenburg, Sweden. 3. Department of Psychiatry, University of Oxford, Oxford, UK. 4. Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Blå Stråket 15, 413 45, Gothenburg, Sweden. mikael.landen@gu.se. 5. Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden. mikael.landen@gu.se.
Abstract
BACKGROUND: Lithium is the best documented maintenance treatment in bipolar disorder, but its use varies considerably across and within countries. It is not known whether regional differences in lithium prescription rates translate to differing regional outcomes. AIMS: To estimate associations between county specific lithium prescription rates and county specific recurrence odds of bipolar disorder in Sweden. METHOD: Data from 14,616 patients with bipolar I disorder, bipolar II disorder, or bipolar disorder not otherwise specified were extracted from the Swedish national quality assurance register for bipolar disorders (BipoläR). Lithium prescription frequencies were calculated for 21 counties. Logistic regression analyses were run adjusted for confounders, with any type of recurrence as primary outcome, and incident elated and depressive episodes as secondary outcomes. Subsets of patients with bipolar I, II and not otherwise specified disorder were also analysed separately. RESULTS: Lithium prescription rates for populations with all bipolar subtypes ranged across counties from 37.7 to 84.9% (mean 52.4%). Higher regional prescription rates were significantly associated with lower rate of any type of recurrence. The association was stronger when bipolar I disorder was analysed separately. CONCLUSIONS: The advantages for lithium use long acknowledged for bipolar I disorder are also seen for the rest of the bipolar spectrum. Results suggest that population level outcomes of bipolar disorder could be improved by increasing the number of patients using lithium.
BACKGROUND:Lithium is the best documented maintenance treatment in bipolar disorder, but its use varies considerably across and within countries. It is not known whether regional differences in lithium prescription rates translate to differing regional outcomes. AIMS: To estimate associations between county specific lithium prescription rates and county specific recurrence odds of bipolar disorder in Sweden. METHOD: Data from 14,616 patients with bipolar I disorder, bipolar II disorder, or bipolar disorder not otherwise specified were extracted from the Swedish national quality assurance register for bipolar disorders (BipoläR). Lithium prescription frequencies were calculated for 21 counties. Logistic regression analyses were run adjusted for confounders, with any type of recurrence as primary outcome, and incident elated and depressive episodes as secondary outcomes. Subsets of patients with bipolar I, II and not otherwise specified disorder were also analysed separately. RESULTS:Lithium prescription rates for populations with all bipolar subtypes ranged across counties from 37.7 to 84.9% (mean 52.4%). Higher regional prescription rates were significantly associated with lower rate of any type of recurrence. The association was stronger when bipolar I disorder was analysed separately. CONCLUSIONS: The advantages for lithium use long acknowledged for bipolar I disorder are also seen for the rest of the bipolar spectrum. Results suggest that population level outcomes of bipolar disorder could be improved by increasing the number of patients using lithium.
Entities:
Keywords:
Bipolar disorder; Drug therapy; Health care quality assessment; Lithium; Outcome assessment