Assessment of Metformin Use Pattern in UK using CPRD

Date of ISAC Approval: 
30/06/2016
Lay Summary: 
Diabetes is one of the most common chronic diseases worldwide. It affects an estimated 415 million people in 2015. Type 2 diabetes mellitus, as the most common form of diabetes, accounts for 85% to 95% of all cases. Metformin is an oral antidiabetic drug and currently is the first-line medication for the treatment of type 2 diabetes. Metformin use, for example, adherence, discontinuation, in recent years is particularly important given the approval of several new drugs for type 2 diabetes treatment. The purpose of this study is to describe latest metformin use pattern in T2D patients including the percentage of patients who discontinued metformin (discontinuation), the percentage of patients who did not take metformin as asked by the physicians (adherence), and the percentage of patient who did not received the maximum dose of metformin (optimal dose). We will further examine what type of patients discontinued metformin, were not adherent to metformin, or never got the maximum dose of metformin. Findings from this study will help to understand the metformin use in the UK and identify potential population who did not receive appropriate treatment for their type 2 diabetes. This study will ultimately to help better manage type 2 diabetes in the UK.
Technical Summary: 
The primary aims to describe metformin use pattern in T2DM patients and the secondary objective is to evaluate factors associated with metformin non-adherence, discontinuation and sub-optimal dose. Exploratory analysis will be conducted to assess metformin use pattern in anti-hyperglycaemic agent(s) (AHA) naive T2DM patients initiating metformin in 2013. Study endpoints include metformin non-adherence, metformin discontinuation, and percentage of patients with sub-optimal metformin dose in the follow-up period (12-months following the index date-dispensing date of the first metformin prescription in 2013). Two multivariate logistic regression analyses will be conducted. One logistic model is to evaluate patient demographic and clinical factors associated with metformin non-adherence (proportion of days covered-PDC <80%) and another is to evaluate factors associated with sub-optimal metformin dose during the follow-up period. For metformin discontinuation, Cox proportional hazards regression model will be conducted to assess factors associated with discontinuation.
Health Outcomes to be Measured: 
Total number of metformin prescriptions Total metformin treatment days Rate of metformin non-adherence (PDC < 80%) Percentage of patients discontinued metformin Percentage of patients with sub-optimal dose
Collaborators: 

Mr Panagiotis Mavros - Chief Investigator - Janssen US
Huang Xingyue - Collaborator - Merck & Co., Inc.
Jinan Liu - Corresponding Applicant - Janssen US