Effect of postmenopausal hormone therapy on glucose and insulin concentrations. PEPI Investigators. Postmenopausal Estrogen/Progestin Interventions.
OBJECTIVE
To characterize the long-term impact of four hormone therapy regimens on insulin and glucose concentrations measured during a standard oral glucose tolerance test.


METHODS
The Postmenopausal Estrogen/Progestin Intervention Study was a 3-year placebo-controlled randomized trial to assess effects of four hormone regimens on cardiovascular risk factors. This efficacy analysis describes glucose and insulin concentrations from 788 adherent women at baseline and at 1 and 3 years' postrandomization.


RESULTS
When compared with women taking placebo, those taking conjugated equine estrogen (CEE) at 0.625 mg/day with or without a progestational agent had mean fasting insulin levels that were 16.1% lower, mean fasting glucose levels 2.2 mg/dl lower, and mean 2-h glucose levels 6.4 mg/dl higher (each nominal P < 0.05). No significant differences were apparent between women taking CEE only versus the three progestin regimens: medroxyprogesterone acetate (MPA) at 2.5 mg daily (continuous MPA), MPA at 10 mg on days 1-12 (cyclical MPA), and micronized progesterone (MP) (cyclical) at 200 mg on days 1-12. The impact of hormone therapy on insulin and glucose depended on baseline levels of fasting insulin and 1-h glucose (P < 0.05). However, the treatment effects on carbohydrate metabolism appeared to be consistent across participant subgroups formed by lifestyle, clinical, and demographic characteristics.


CONCLUSIONS
Oral hormone therapy involving 0.625 mg/day of CEE may modestly decrease fasting levels of insulin and glucose. Postchallenge glucose concentrations are increased, however, which may indicate delayed glucose clearance.
Espeland
M A
MA
Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157-1063, USA. mespelan@rc.phs.wfubmc.edu
Hogan
P E
PE
Fineberg
S E
SE
Howard
G
G
Schrott
H
H
Waclawiw
M A
MA
Bush
T L
TL
D001786:Blood Glucose / Q000378:metabolism*; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination; D015914:Estrogen Replacement Therapy; D004966:Estrogens, Conjugated (USP) / Q000627:therapeutic use*; D005215:Fasting; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007328:Insulin / Q000097:blood*; D017258:Medroxyprogesterone Acetate / Q000627:therapeutic use*; D010919:Placebos; D017698:Postmenopause / Q000097:blood*; D019518:Postprandial Period; D011374:Progesterone / Q000627:therapeutic use*; D045167:Progesterone Congeners / Q000627:therapeutic use; D013997:Time Factors
D001786:Blood Glucose; D004966:Estrogens, Conjugated (USP); D007328:Insulin; D010919:Placebos; D045167:Progesterone Congeners; D011374:Progesterone; D017258:Medroxyprogesterone Acetate