Presentations

Abstract

Introduction: Type 2 diabetes mellitus develops from chronically increased blood sugar (glucose) levels. Insulin normally regulates movement of glucose into cells, but in type 2 diabetes mellitus, cells develop insulin resistance and thus take in less glucose from the blood. Furthermore, with type 2 diabetes mellitus, the pancreas does not produce enough insulin to effectively reduce blood sugar levels. In use for type 2 diabetes mellitus, Metformin functions to increase insulin sensitivity of cells and reduce blood sugar levels. Metformin remains first line medical therapy for most patients with type 2 diabetes mellitus but is felt to be underutilized due to a high discontinuation (DC) rate. The DC rate in one large study was 50% within one year after starting. This rate is similar to the discontinuation rate of other DM medications which highlights the importance of proactively addressing issues related to medication adherence for all DM patients. The reasons for stopping Metformin are multiple, but many are felt to be preventable patient factors, provider actions, or omissions. A common patient factor is GI side effects. One review showed that this factor is often related to not using the recommended Metformin ER formulation at the lowest dose initially with no titration upwards until any GI symptoms abate. At Ghent Family Medicine (GFM), one recent example of provider actions leading to Metformin discontinuation was Metformin being dropped off the medication list on hospital discharge summary despite no medical indication. This change was not addressed after discharge until the 3rd office visit 1 year later, at which time A1c had increased from 7.8 to 9.1 on insulin alone. A more common provider factor is concern for renal effects of Metformin, with some providers not aware of more recent guidelines recommending Metformin for glomerular filtration rate (GFR) > 30, changed from >45 previously. Additionally, Metformin has been shown to be more effective than sulfonylureas or insulin (both of which are often used as Metformin replacements) in preserving GFR. Another impact of Metformin DC is the increased cost for the US Health Care system and taxpayers. The increasingly popular glucagon like peptide (GLP-1) and sodium glucose transporter (SGLT) inhibitors are at least 15 times more expensive than Metformin yet show similar A1c improvement as first line monotherapy as demonstrated in one large study. A 2022 cost effectiveness analysis concluded that for GLP-1 and SGLT2 agents to be as cost effective as Metformin as a first line monotherapy, the prices would need to fall by 90% and 70% respectively.

Methods: Medical records of eligible patients will be reviewed to collect retrospective data related to their type 2 diabetes mellitus diagnosis and Metformin discontinuation. Medical records from January 1, 2018 up to December 26, 2023 will be reviewed. Data to be collected includes: age at time of initial DM diagnosis, BMI, A1c, GFR, Metformin start date, Metformin dose with dose frequency and changes, reason for Metformin discontinuation, Metformin discontinuation date, and other DM medications. Statistical analyses will be mainly descriptive. Reasons for Metformin discontinuation will be classified as preventable, possibly preventable, not preventable, or unable to be determined. Metformin discontinuation will be calculated as a percentage at 1 and 2 year intervals overall and among classifications. Average and changes in A1c and BMI values will be compared between patients remaining on Metformin and those who have discontinued it.

Results: Data collection is currently in process.

Conclusion: We will be determining Metformin discontinuation rate at Ghent Family Medicine. Additionally, we will be reviewing reasons for Metformin discontinuation and comparing A1c and BMI in patients remaining on Metformin to those who discontinued it. With this analysis, we aim to identify trends that would better inform future strategies in lowering Metformin discontinuation rates as well as overall DM management.