Vascular function of forearm microcirculation in postmenopausal women with type 2 diabetes: potential benefit of hormone replacement therapy?
OBJECTIVE
To study the potential effects of hormone replacement therapy (HRT) on vascular function of the peripheral circulation in postmenopausal women with type 2 diabetes.


METHODS
Seventeen premenopausal women aged 47.4 +/- 4.4 years (PreM), 23 nondiabetic postmenopausal women aged 59.4 +/- 7.0 years (PM), 15 postmenopausal women with type 2 diabetes aged 60.3 +/- 7.2 years (PMD) and 12 postmenopausal women with type 2 diabetes using HRT aged 61.2 +/- 4.0 years (PMDHRT) were studied. Vascular function of the peripheral circulation was investigated by measuring hyperemic responses of the forearm microcirculation following an ischemic stimulus using venous occlusion, strain-gauge plethysmography. Fasting lipids, glucose and glycated hemoglobin (HbA1c) were also measured.


RESULTS
Forearm vascular function was significantly impaired in the PMD group: maximal blood flow (ml/100 ml/min) was 15.23 +/- 8.19 vs. 28.21 +/- 12.30 (PreM), 23.62 +/- 6.62 (PM) and 23.37 +/- 5.78 (PMDHRT) (p = 0.004); flow debt (ml/100 ml) was 3.99 +/- 2.83 vs. 7.40 +/- 4.92 (PreM), 5.66 +/- 3.67 (PM) and 8.57 +/- 4.84 (PMDHRT) (p = 0.0018); vascular resistance (mmHg/ml/100 ml/min) was 11.90 +/- 9.02 vs. 5.04 +/- 2.41 (PreM), 5.55 +/- 2.69 (PM) and 5.96 +/- 1.88 (PMDHRT) (p = 0.003). Fasting lipids, HbA1c and body mass index were not significantly different between the two diabetic groups.


CONCLUSIONS
Postmenopausal women with diabetes have abnormal vascular function of resistance arteries that may improve with HRT. HRT may therefore reduce cardiovascular risk in postmenopausal women with type 2 diabetes, and a clinical end-point trial is warranted to test this hypothesis.
Ching
H L
HL
Keogh Institute for Medical Research, Sir Charles Gairdner Hospital, Nedlands, WA 6009, Australia.
Watts
G F
GF
Dhaliwal
S S
SS
Barrett
P H R
PH
Stuckey
B G A
BG
D000328:Adult; D000368:Aged; D001783:Blood Flow Velocity; D001786:Blood Glucose; D001794:Blood Pressure; D002784:Cholesterol / Q000097:blood; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000503:physiopathology*; D015914:Estrogen Replacement Therapy; D005260:Female; D005542:Forearm; D006442:Glycated Hemoglobin; D006801:Humans; D008833:Microcirculation / Q000187:drug effects / Q000502:physiology*; D008875:Middle Aged; D017698:Postmenopause; D012867:Skin / Q000098:blood supply*; D014655:Vascular Resistance
D001786:Blood Glucose; D002784:Cholesterol; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D006442:Glycated Hemoglobin