Autonomic neuropathy influences great toe blood pressure.
OBJECTIVE
To assess the influence of autonomic neuropathy on toe blood pressure (TBP), a parameter used currently as an ischemic index.


METHODS
The age-matched study subjects included 20 non-insulin-dependent diabetes mellitus (NIDDM) patients with autonomic neuropathy (DN) and 10 NIDDM patients without autonomic neuropathy (D), assessed by standard cardiovascular tests and galvanic skin response, and 8 control subjects (C). None of the subjects had peripheral vascular disease (PVD) (ankle/brachial index 0.9-1.1.


RESULTS
The TBP and toe/brachial index (TBI) were significantly lower in DN than in C and D (P < 0.01). The saturation index (SI), the ratio between foot venous and arterial partial pressure of oxygen (PO2), was significantly higher in DN than in C and D (P < 0.05). An inverse relationship was found between TBI and SI (r = 0.554, P = 0.001).


CONCLUSIONS
The autonomic nervous system directly influences peripheral circulation. In diabetic patients without PVD, a failure of sympathetic fibers caused by autonomic neuropathy could lead to a reduction of TBP. Therefore, TBP cannot be used as an ischemic index in diabetic patients.
Department of Endocrinology, University of Rome, Tor Vergata, Italy.
L
L
Uccioli
G
G
Monticone
L
L
Durola
F
F
Russo
F
F
Mormile
G
G
Mennuni
G
G
Menzinger
D000704:Analysis of Variance; D000842:Ankle / Q000098:blood supply; D001341:Autonomic Nervous System / Q000503:physiopathology; D001785:Blood Gas Monitoring, Transcutaneous; D001794:Blood Pressure; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000503:physiopathology*; D003929:Diabetic Neuropathies / Q000097:blood / Q000503:physiopathology*; D006801:Humans; D007024:Hypotension, Orthostatic; D008875:Middle Aged; D010100:Oxygen / Q000097:blood; D010313:Partial Pressure; D011187:Posture; D012044:Regression Analysis; D012119:Respiration; D013599:Systole; D013909:Thorax; D014034:Toes / Q000098:blood supply*; D014636:Valsalva Maneuver
D010100:Oxygen