Prevalence and Risk Factors of Lithium Toxicity at Srinagarind Hospital

Abstract

Background: Lithium is commonly used in the treatment of bipolar disorder. Lithium has narrow therapeutic range; its toxicity therefore is also a frequent complication of chronic lithium therapy.

Objective:  The purposes of this study were to determine the prevalence and risk factors of lithium toxicity in Thai patients at Srinagarind Hospital in Khon Kaen.

Methods: This descriptive retrospective study was performed by reviewing the OPD cards and medical records of patients who had received lithium during the period from 1 January 2003 to 31 May 2006.

Results: There were 273 patients (308 visits) who had relevant OPD card and medical records. 65 patients had lithium toxicity of which 12 (3.9%) were from IPD and 53 (17.2%) were from OPD. The prevalence per year was 14.1% in 2003, 20.2% in 2004 and 31.7% in 2005. Lithium toxicity was classified as mild (42 reports, 64.4%), moderate (20 reports, 30.8%) and severe (3 reports, 4.6%), respectively. Risk factors for lithium toxicity were a dose of 900-1200 mg (OR: 2.2; 95% CI 1.2 to 4.2), a dose more than 1200 mg (OR: 5.4; 95% CI 1.8 to 16.6), patients with schizophrenia (OR: 3.3; 95% CI 1.1 to 10.1) and patients who received SSRIs drugs (OR: 2.8; 95% CI 1.3 to 6.1).

Conclusion: The finding of this study supported that the use of lithium for treatment of bipolar disorder should be close monitored especially in the patients who received a dose of more than 900 mg, especially patients with schizophrenia and patients who received SSRIs drugs