The incidence of T2DM is increasing worldwide and treatments that are implementable in primary care could contribute greatly to the prevention/remission of T2DM. Previous studies have shown that weight loss can improve quality of life and help achieve normal blood glucose levels in overweight/obese patients with T2DM/prediabetes. However, weight loss and weight management can be challenging for many using only lifestyle modifications. NICE guidelines for managing diabetes recommend orlistat for reducing weight in patients who are overweight/obese. Side effects may occur within the first 12 weeks of using orlistat and guidelines suggest treatment may be continued beyond 12 weeks only if weight loss since the start of treatment exceeds 5%. The study objectives are to determine: (i) the incidence of orlistat and (ii) metformin prescriptions in patients with incident T2DM/prediabetes in primary care; (ii) if orlistat is prescribed according to NICE guidelines; (iii) whether patient characteristics including body mass index (BMI) and socio-demographics, including linkage to deprivation, are associated with: (a) prescribing of orlistat (b) stopping orlistat early; (iv) the association of orlistat with long term outcomes including weight loss, and reductions in haemoglobin A1c (HbA1c), fasting plasma glucose (FPG) and blood pressure (BP). Patients diagnosed with incident T2DM or prediabetes between 1.1.2016 and 31.12.2017, and ≥18 years of age will be included and followed up in their primary care records for 2 years. For each patient, the closest recorded BMI in the baseline period 2 years prior to diagnosis will be identified. First record of receiving orlistat anytime from 12 weeks prior to diagnosis will be extracted. The incidence of orlistat prescribing per 1000 person years at risk with 95% confidence intervals (CIs) will be determined. Multivariable regression models will be fitted to estimate associations of BMI and the other outcomes with prescribing of orlistat in patients with T2DM/prediabetes.
In patients with T2DM or prediabetes:
Primary outcomes: (i) Prescription of orlistat and metformin (ii) change in weight/BMI.
Secondary outcomes: (i) change in HbA1c (ii) change in FPG (iii) change in BP (iv) proportion of patients with BMI <28 kg/m2 and T2DM/prediabetes prescribed orlistat (v) incidence of T2DM (prediabetes only).
Shraboni Ghosal - Chief Investigator - Keele University
Shraboni Ghosal - Corresponding Applicant - Keele University
James Bailey - Collaborator - Keele University
Kayleigh Mason - Collaborator - Keele University
Kelvin Jordan - Collaborator - Keele University
Neil Heron - Collaborator - Keele University
Patient Level Index of Multiple Deprivation