Treatment with montelukast and antidepressive medication-a symmetry analysis.

PURPOSE: Leukotriene receptor antagonists are used in asthma and rhinitis treatment. Pharmacovigilance data have suggested an association between montelukast and depression, but the association has not been established in controlled study designs. We described the association between initiation of montelukast and depression, using prescriptions of antidepressants as a surrogate marker, and assessed whether the association was related to the underlying asthma disease. METHODS: We performed a symmetry analysis, with a study period from January 1, 2000 to December 31, 2016, using 3 nationwide Danish registers. We included all adults, who filled their first prescription of montelukast and antidepressants within an interval of 1 year. In the absence of an association between montelukast and antidepressant use, a symmetrical distribution of prescriptions is expected before and after montelukast initiation (ie, a sequence ratio [rc ] of 1.0). We subcategorized the subjects after the severity of underlying asthma disease. RESULTS: In total, 4450 subjects filled their first prescriptions of both montelukast and antidepressants within a 1-year interval: 2434 redeemed their first prescription of montelukast before antidepressants, and 2016 redeemed the medications in the opposite order (rc 1.21 [95% CI 1.14-1.28]). We found rc above unity in groups with long-acting asthma treatment, but no increase in antidepressant prescription, when stratifying by the asthma severity. CONCLUSION: We found a weak association between the use of montelukast and the risk of being prescribed an antidepressant, unlikely to be of clinical relevance. Stratified analyses suggest that this association may relate to asthma, rather than to montelukast.

Lithium and the risk of chronic kidney disease: A population-based case-control study.

The association between lithium use and chronic kidney disease (CKD) needs further evaluation. We aimed to investigate this association using Danish nationwide healthcare registers and routinely collected plasma creatinine measurements from the Funen Laboratory Cohort. We conducted a case-control study nested within the population of Funen, 2001-2015. Incident cases of CKD (estimated glomerular filtration rate <60 ml/min/1.73m2 ; n = 21 432) were matched with four CKD-free controls on age, sex and calendar time (n = 85 532). We estimated odds ratios (OR) for the association between lithium exposure and CKD using conditional logistic regression models, adjusted for known risk factors for CKD. Ever-use of lithium was associated with an increased risk of CKD (adjusted OR [aOR]: 1.57; 95% confidence interval [CI]: 1.33-1.85). A stronger association was seen with current use of lithium (aOR: 1.92; 95%CI: 1.58-2.33) and long-term use of lithium (>10 years: aOR: 3.02; 95%CI: 2.00-4.56). Furthermore, we found evidence of a dose-response relationship between cumulative dose of lithium and the risk of CKD. In conclusion, the use of lithium, especially long-term, is associated with an increased risk of CKD, although the extent to which detection bias and confounding by indication contribute to the association is unclear. Monitoring of kidney function in lithium users remains mandatory to identify individuals in which switching to alternative medications should be considered.