This is an observational clinical study, patients with systemic diseases will be enrolled according to the inclusion and exclusion criteria. 360 patients will received the examination of sublingual microcirculation by using sidestream dark filed video microscope. The microcirculation data includes total small vessel density, perfused small vessel density, microvascular flow index, and heterogeneity index. The patients will be divided into right groups according to their systemic diseases as follows: group 1 hypertension (60 patients), group 2 diabetes mellitus (60), group 3 hypertension and diabetes mellitus (60), group 4 end stage renal disease with hemodialysis (60), group 5 peripheral arterial occlusive disease (30), group 6 coronary artery disease (30), group 7 liver cirrhosis (30), and group 8 anemia (30).

Inclusion Criteria:

• Patients aged from 20 to 79 years old

• BMI ranged from 18.5 to 27 kg/m2

• Presence of one of the condition

  1. Diagnosed hypertenison > 6 months, without other systemic diseases
  2. Diagnosed diabetes mellitus > 6 monthes, without other systemic diseases
  3. Diagnosed with both hypertension and diabetes mellitus > 6 months, without other systemic diseases
  4. Diagnosed with end stage renal disease and recevied renal replacement therapy > 6 months
  5. Diagnosed with peripheral arterial occlusive diseases > 6 months
  6. Diagnosed with coronary artery disease > 6 months
  7. Diagnosed with liver cirrhosis > 6 months
  8. Diagnosed with anemia > 6 months, hemoglobin level < 10 g/dL

Exclusion Criteria:

• Diagnosed with sepsis, major tauma, or admission to ICU within one month

• Body temperature higher than 37.5 ℃ or lower than 35.5 ℃

• Any on of the following condition

  1. Asthma
  2. Chronic obstructive pulmonary disease
  3. Endocrine diseases
  4. Hematological disorders
  5. Uncured cancer
  6. Chronic uncured infection
  7. Other major disease with limited daily activity

• Non-native speakers

Patients with diagnosed hypertension, diabetes mellitus, both hypertension and diabetes mellitus, end stage renal disease with hemodialysis, peripheral arterial occlusive disease, coronary artery disease, liver cirrhosis, or anemia.