The diagnosis of type 2 diabetes mellitus is made on the basis of the clinical picture and laboratory parameters.Optional medical device diagnostics – depending on the results of the history, physical examination and laboratory diagnostics – to identify secondary diseases of diabetes mellitus.
- Cardiovascular diagnostics
- Repeated blood pressure measurement on both arms with cuff adjusted to arm circumference.
- 24-hour blood pressure measurement [not infrequently there is masked hypertension/high blood pressure].
- Ankle-brachial index (ABI; examination method that can describe the risk of cardiovascular disease) – in case of non-palpable or weakly palpable foot pulses (caveat: mediasclerosis).
- Transcranial Doppler sonography (ultrasound examination through the intact skull for orienting control of cerebral (“concerning the brain“) blood flow; brain ultrasound).
- Doppler sonography of the carotids (carotid arteries) – evidence of stenosis, plaques, or intima-media thickening (IMT) of the carotids indicate a 6-, 4-, and 2-fold increased risk of myocardial infarction (heart attack), respectively
- Exercise ECG (electrocardiogram during exercise, that is, under physical activity/exercise ergometry) – if myocardial ischemia (insufficient supply of the heart muscle (myocardium) with arterial blood) and normal resting ECG is suspected.
- Cardio-computed tomography (cardio-CT) – early detection of coronary vascular calcification.
- Cardiac catheter examination
- Liver ultrasonography (liver ultrasound) – 2 out of 3 diabetic patients have fatty liver.
- Renal sonography (ultrasound examination of the kidneys) including the urinary tract – if renal dysfunction is suspected.
- Pancreatic ultrasonography (ultrasound examination of the pancreas) – once in new-onset diabetes mellitus; as pancreatic cancer screening in case of positive family history or genetic risk for pancreatic cancer (pancreatic cancer).
- Electrocardiogram (ECG; recording of the electrical activity of the heart muscle) – signs of an elapsed (silent) infarct?; look for signs of ischemia such as ST-segment and T-wave changes (compared with pre-ECG) and Q-wave spikes or R-wave reductions.
- Echocardiography (echo; cardiac ultrasound) – as a regular cardiac check-up, especially to detect a new contractile dysfunction.
- Ergometry/load ECG – detection of ischemia (reduced blood flow to the myocardium) and to assess exercise capacity in watts (prognostic marker), sinus frequency ( chronotropic incompetence?, cardiac autonomic neuropathy?) and repolarization (T-wave alternans test, if applicable).
- Long-term ECG – to investigate /determine:
- Cardiac arrhythmias: asymptomatic atrial fibrillation, complex ventricular arrhythmia (especially non-sustained ventricular tachycardia) and bradycardia.
- Mean heart rate and heart rate variability (cardiac autonomic neuropathy?).
- Ophthalmologic examination (see “Further therapy” below).
- Visual acuity determination (determination of visual acuity); examination of the anterior segments of the eye.
- Funduscopy (reflection of the fundus of the eye, i.e., examination of the retina) with dilated pupil.
