Venoarteriolar reflex responses in diabetic patients

Area of Science:

• Cardiovascular Physiology
• Diabetology
• Neurology

Background:

• Diabetes mellitus (DM) is associated with microvascular complications, including polyneuropathy.
• The venoarteriolar reflex (VAR) is a critical mechanism regulating cutaneous blood flow.
• Impaired VAR responses may contribute to diabetic complications.

Purpose of the Study:

• To investigate VAR responses in patients with type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM) who have polyneuropathy.
• To assess the relationship between VAR responses and factors like age, DM duration, initial skin temperature, and body mass index (BMI).

Main Methods:

• Comparison of VAR responses between T1DM patients, T2DM patients, and age/BMI-matched healthy controls.
• Monitoring of cutaneous blood perfusion in the big toe pulp under controlled temperature conditions (32°C).
• Assessment of VAR in supine, sitting with legs dependent, and supine positions.

Main Results:

• Loss of VAR responses was observed in 75% of T1DM patients and 78% of T2DM patients, versus none in controls.
• Reduced venoarteriolar perfusion responses were evident in both diabetic groups compared to healthy subjects.
• Positive associations were found between VAR responses and age, DM duration, and initial cutaneous temperature.

Conclusions:

• Polyneuropathy in T1DM and T2DM significantly impairs venoarteriolar reflex responses.
• VAR impairment is linked to key diabetes-related factors, highlighting its clinical relevance.
• These findings suggest VAR assessment could be valuable in managing diabetic microvascular complications.