Case study: when it’s time to turn to a DPP-4 inhibitor

The case

Jimmy is a 76-year-old retired teacher who lives alone and was diagnosed with type 2 diabetes (T2D) five years ago, and has been maintained on metformin 850 mg twice daily.

Presenting condition and symptoms

He presents for a routine visit and, as part of pathology testing, the HbA1c was noted to be 7.7%. Just six months ago, the HbA1c was only 7.1%, which was close to his designated HbA1c target of 7.0%. On questioning, he has no symptoms of hyperglycaemia.

Medical history

As well as his five-year history of T2D, he is also overweight with a BMI of 28 kg/m2. His current dose of metformin was the maximum tolerated dose – higher doses caused gastrointestinal side effects.

Jimmy had well-controlled hypertension (BP 130/78 mmHg) and dyslipidaemia (LDL 2.1 mmol/L).

He is known to have some microalbuminuria (urine albumin-to-creatinine ratio [uACR] 12.6 mg/mmol) and stable renal impairment (eGFR 42 ml/min/1.73m2.

While he has minimal retinopathy, he is free of any other diabetes complications such as overt cardiovascular disease or peripheral neuropathy.

Medication history

  • Metformin 850 mg bd
  • Telmisartan 80 mg daily
  • Atorvastatin 20 mg daily