Weight Trajectory in New Users of Sulfonylureas as Add on Therapy Next to Metformin.

Study Overview
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Brief Summary
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Next to HbA1c, body weight is regarded as an important surrogate end-point in trials investigating glucose-lowering agents. An increase in weight could contribute to worsening insulin resistance. Differences in weight after starting glucose lowering agents have been described in many randomized controlled trials (RCTs). With this prospective observational study, weight trajectories after receiving add-on therapy next to metformin are evaluated in primary care patients with good glycaemic control.

Detailed Description
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This prospective cohort study is part of the ZODIAC (Zwolle Outpatient Diabetes project Integrating Available Care) study, which started in 1998 as a prospective observational study and includes patients with known T2DM who are treated in primary care. The investigators aim to investigate the course of the bodyweight and glycaemic control, the years after starting specific SU's, pioglitazone or insulin as add-on therapy, in metformin treated primary care patients with T2DM. As part of the process called benchmarking, a dataset of quality measures is collected annually for all patients participating in the ZODIAC study during the patient's visit to the practice nurse and/or general practitioner and sent to the investigators' diabetes centre for benchmarking and research purposes once a year.

Official Title
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A Prospective Observational Cohort Study; The Weight Trajectory in New Users of Sulfonylureas as Add on Therapy Next to Metformin.

Conditions
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Type 2 Diabetes Mellitus

Intervention / Treatment
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* Drug: individual SUs, insulin, pioglitazone


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: T2DM Treated in primary care in period 1998 to 2012 used metformin monotherapy subsequently received add-on therapy with a SU or pioglitazone during their entire follow-up period
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patients on metformin mono-therapy who receive add-on<br> | Drug: individual SUs, insulin, pioglitazone<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The course of weight (Kg) after starting individual SU's, pioglitazone or insulin as add-on therapy. | The course of the bodyweight up to five years after starting individual SU's (gliclazide/glibenclamide/tolbutamide/glimepiride), pioglitazone or insulin as add-on therapy, in metformin treated primary care patients with T2DM. | Up to 5 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The course of the glycaemic control (HbA1c %) , up to five years after starting individual SU's, pioglitazone or insulin as add-on therapy. | The course of the glycaemic control, up to five years after starting individual SU's (gliclazide, glibenclamide, tolbutamide, glimepiride), pioglitazone or insulin as add-on therapy, in metformin treated primary care patients with T2DM. | Up to 5 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Type 2 diabetes, New-user design, Weight trajectory, Add-on therapy, Sulphonylureas.