Long-term effects of lithium on renal function

Abstract

The Article by Brian Shine and colleagues1Shine B McKnight RF Leaver L Geddes JR Long-term effects of lithium on renal, thyroid, and parathyroid function: a retrospective analysis of laboratory data.Lancet. 2015; 386: 461-468Summary Full Text Full Text PDF PubMed Scopus (161) Google Scholar is the best accounting of the long-term adverse effects associated with lithium treatment that has ever been published, and the authors deserve high praise. However, like all strong studies, it answers some questions and poses others. For instance, the analysis suggests that male patients younger than 60 years will have almost no greater decline in renal function than control patients for more than 20 years of treatment (figure 3).1Shine B McKnight RF Leaver L Geddes JR Long-term effects of lithium on renal, thyroid, and parathyroid function: a retrospective analysis of laboratory data.Lancet. 2015; 386: 461-468Summary Full Text Full Text PDF PubMed Scopus (161) Google Scholar But this conclusion might inadvertently combine the effects of lithium treatment duration and age.An important clinical question presents itself: in patients younger than 60 years, will a patient who began lithium at age 20, and is therefore 45 years old at 25 years of lithium treatment, have the same average renal decline as the patient who starts lithium at age 33, and is therefore 58 years old at 25 years of lithium? Would the investigators be able to provide an age-duration (of lithium treatment) interaction term coefficient for patients younger than 60 years, or other analyses that might help to answer this question? The results would be valuable to clinicians and researchers alike, and make a strong study even stronger.I declare no competing interests. The views expressed are those of the author and do not necessarily reflect the position or policy of the Department of Veterans Affairs or the United States Government. The Article by Brian Shine and colleagues1Shine B McKnight RF Leaver L Geddes JR Long-term effects of lithium on renal, thyroid, and parathyroid function: a retrospective analysis of laboratory data.Lancet. 2015; 386: 461-468Summary Full Text Full Text PDF PubMed Scopus (161) Google Scholar is the best accounting of the long-term adverse effects associated with lithium treatment that has ever been published, and the authors deserve high praise. However, like all strong studies, it answers some questions and poses others. For instance, the analysis suggests that male patients younger than 60 years will have almost no greater decline in renal function than control patients for more than 20 years of treatment (figure 3).1Shine B McKnight RF Leaver L Geddes JR Long-term effects of lithium on renal, thyroid, and parathyroid function: a retrospective analysis of laboratory data.Lancet. 2015; 386: 461-468Summary Full Text Full Text PDF PubMed Scopus (161) Google Scholar But this conclusion might inadvertently combine the effects of lithium treatment duration and age. An important clinical question presents itself: in patients younger than 60 years, will a patient who began lithium at age 20, and is therefore 45 years old at 25 years of lithium treatment, have the same average renal decline as the patient who starts lithium at age 33, and is therefore 58 years old at 25 years of lithium? Would the investigators be able to provide an age-duration (of lithium treatment) interaction term coefficient for patients younger than 60 years, or other analyses that might help to answer this question? The results would be valuable to clinicians and researchers alike, and make a strong study even stronger. I declare no competing interests. The views expressed are those of the author and do not necessarily reflect the position or policy of the Department of Veterans Affairs or the United States Government. Long-term effects of lithium on renal, thyroid, and parathyroid function: a retrospective analysis of laboratory dataLithium treatment is associated with a decline in renal function, hypothyroidism, and hypercalcaemia. Women younger than 60 years and people with lithium concentrations higher than median are at greatest risk. Because lithium remains a treatment of choice for bipolar disorder, patients need baseline measures of renal, thyroid, and parathyroid function and regular long-term monitoring. Full-Text PDF Open AccessLong-term effects of lithium on renal function – Authors' replyWe thank Parminder Judge and Christopher Winearls, Eric Smith, Mohamad Zaidan, and Soham Rej and colleagues for their comments on our study1 and helpful suggestions for future investigation. Full-Text PDF