First‐line pharmacotherapy for incident type 2 diabetes: Prescription patterns, adherence and associated costs

Abstract

Aims To use real‐world prescription data from Alberta, Canada to: (a) describe the prescribing patterns for initial pharmacotherapy for those with newly diagnosed uncomplicated type 2 diabetes; (b) describe medication‐taking behaviours (adherence and persistence) in the first year after initiating pharmacotherapy; and (c) explore healthcare system costs associated with prescribing patterns. Methods We employed a retrospective cohort design using linked administrative datasets from 2012 to 2017 to define a cohort of those with uncomplicated incident diabetes. We summarized the initial prescription patterns, adherence and costs (healthcare and pharmaceutical) over the first year after initiation of pharmacotherapy. Using multivariable regression, we determined the association of these outcomes with various sociodemographic characteristics. Results The majority of individuals for whom metformin was indicated as first‐line therapy received a prescription for metformin monotherapy (89%). Older individuals, those with higher baseline A1C and those with no comorbidities, were most likely to be started on non‐metformin agents. Adherence with the initially prescribed regimen was suboptimal overall, with nearly half (48%) being non‐adherent over the first year. One‐third of those who started metformin discontinued it in the first 3 months. Those started on non‐metformin agents had roughly twice the healthcare costs, and five to seven times higher medication costs, compared to those started on metformin, in the first year after starting therapy. Conclusions With the addition of new classes of medications, healthcare providers who look after those with type 2 diabetes have more pharmaceutical options than ever. Most individuals continue to be prescribed metformin monotherapy. However, adherence is suboptimal, and drops off considerably within the first 3 months.

Metformin: Is it a drug for all reasons and diseases?

“…Compliance, however, may be much lower than previously considered as a retrospective cohort study of 15,981 patients indicated 48% became nonadherent within the first year of treatment with metformin [29]. Discontinuance of metformin is primarily attributed either to side effects, or glycemic control being achieved independent of pharmacotherapy [29]. Similarly, a 2018 report indicated that 30% of prescribed doses of metformin were not taken, whereas higher adherence was seen for sulfonylureas, diphenyly-peptide-4 inhibitors (DPP-4 inhibitors, or gliptins) and sodium-glucose co-transport inhibitors-2 (SGLT-2, or gliflozins), but not for glucagon-like peptide-1 receptor agonists (GLP-1 receptor agonists) [29].…”

“…The usual dose-range for metformin is from 250 to 2550 mg/day with plasma levels ranging from approximately 5 to 20 μM (Table 2). Compliance, however, may be much lower than previously considered as a retrospective cohort study of 15,981 patients indicated 48% became nonadherent within the first year of treatment with metformin [29]. Discontinuance of metformin is primarily attributed either to side effects, or glycemic control being achieved independent of pharmacotherapy [29].…”

“…Discontinuance of metformin is primarily attributed either to side effects, or glycemic control being achieved independent of pharmacotherapy [29]. Similarly, a 2018 report indicated that 30% of prescribed doses of metformin were not taken, whereas higher adherence was seen for sulfonylureas, diphenyly-peptide-4 inhibitors (DPP-4 inhibitors, or gliptins) and sodium-glucose co-transport inhibitors-2 (SGLT-2, or gliflozins), but not for glucagon-like peptide-1 receptor agonists (GLP-1 receptor agonists) [29]. In the latter study it was noted that whereas DPP-4 inhibitors were generally well-tolerated, GI side effects were more frequently associated with metformin and attributed to the lower adherence with the biguanide [30].…”

COVID-19 and the prevalence of drug shortages in Canada: a cross-sectional time-series analysis from April 2017 to April 2022

“…35 This highlights the value of prioritizing shortages that pose the greatest risk to patients — an exercise operationalized in March 2020. 36 …”

Nutraceutical Treatment of Patients with Polycystic Ovary Syndrome

“…Patients suffering from PCOS are at risk of long-term negative health hazards that are not, or only partly addressed by the usual allopathic treatments, the adherence to which is suboptimal in real-world [33]. In addition, Metformin may induce Vitamin B12 deficiency [34].…”