Use of GLP-1 receptor agonists (GLP-1 RAs) is an established therapy that delays progression of chronic kidney disease in type 2 diabetes mellitus (T2DM), but their impact on lithium-associated nephrotoxicity is unclear. We evaluated whether GLP-1 RA use is associated with reduced renal risk in adults receiving long-term lithium therapy.

We conducted a retrospective, propensity score-matched cohort study using TriNetX electronic health records (>127 million patients across 109 healthcare organizations). Adults (≥18 years) with T2DM and lithium exposure within 2 years prior to index were included. The primary outcome was renal nephrotoxicity, defined as a composite of ICD-10 and CPT-coded renal disease. Incidence and time-to-event outcomes were assessed using Kaplan–Meier curves and Cox proportional hazards models.

In a 24-month analysis of 452 matched patient pairs, GLP-1 RA initiation during lithium therapy was associated with a marked reduction in renal events versus lithium alone (23.5% vs 44.7%), corresponding to a risk difference of −21.2% (95% CI -36.9 to −5.5) and a risk ratio of 0.53 (95% CI 0.30–0.91; p = 0.013). Event-free survival was higher (62.5% vs 43.4%; log-rank p = 0.0115), with a hazard ratio of 0.45 (95% CI 0.23–0.85; p = 0.0089). This represents a 47% relative risk reduction and a number needed to treat (NNT) of 5 over 24 months.

These findings support further mechanistic and prospective studies of GLP-1 RAs as a renoprotective strategy for patients receiving lithium treatment.

The appropriate monitoring of patients on lithium therapy has been the subject of extensive research in the form of clinical audits and surveys culminating in the development of specific guidelines to help clinicians provide optimal care for patients on lithium. The concept of ‘shared care’ has also gained attention in the literature with various types of shared care interventions being introduced as potential ways of improving communication between primary and secondary care.

This article aims to (1) review the literature evaluating lithium monitoring practices in the United Kingdom and Ireland in the last 25 years and (2) determine whether locally agreed shared care agreements have the potential to improve monitoring quality.

A literature search was conducted using the following databases: PubMed, Scopus, Web of Science, Academic Search Premier, CINAHL and PsychInfo. A total of 12 studies were selected for review including 11 audits/prospective chart reviews and one qualitative study using semi-structured interviews.

Overall, the quality of lithium monitoring seems to be improving throughout the years. However, none of the studies reviewed revealed complete adherence to monitoring guidelines. This may be due to a lack of effective communication between primary and secondary care. Several shared care interventions have been described in the literature but there is a paucity of studies concerned with the effects of local shared care arrangements designed for the specific purpose of lithium monitoring. Nonetheless, the extant data suggests that such agreements may help improve monitoring standards by allowing the responsibilities for managing the prescribing and monitoring of lithium to be more clearly defined and shared between primary and secondary care.