Use of combined oral contraceptive preparations alters the insulin sensitivity of fatty acid and ketone metabolism.
Eight women taking low-dose-oestrogen combined oral contraceptive preparations were compared to eight women in the luteal phase of the menstrual cycle during hourly incremental insulin infusions of 0 (basal), 0.005, 0.01 and 0.05 U/kg/h short-acting insulin. Dose-response relationships between insulin and intermediary metabolites were sought by analysis of variance applied to regression. For insulin (log) and glucose the slope of the relationship was significantly shallower in the oral contraceptive group. For insulin (log) and non-esterified fatty acids the slopes of the regression lines were not different between groups but lines were significantly displaced. For insulin (log) and total ketone bodies (log) slopes of the regression lines were not different but significant displacement was observed. At identical insulin concentrations women taking an oral contraceptive had higher non-esterified fatty acids (NEFA) (difference between groups +0.15 mmol/l, P less than 0.001) and total ketone bodies (log: -0.26 mmol/l, P less than 0.001). The potency of insulin action in oral contraceptive users versus the luteal group was 0.47 (P less than 0.01) for NEFA and 0.38 (P less than 0.001) for total ketone bodies. The results demonstrate, for the first time, in-vivo insulin resistance of NEFA and ketone bodies' metabolism induced by oral contraceptive use.
Singh
B M
BM
Diabetic Clinic, General Hospital, Birmingham, UK.
Nattrass
M
M
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D003277:Contraceptives, Oral, Combined / Q000009:adverse effects*; D005230:Fatty Acids, Nonesterified / Q000097:blood*; D005260:Female; D005990:Glycerol / Q000097:blood; D006801:Humans; D007328:Insulin / Q000097:blood / Q000502:physiology*; D007659:Ketones / Q000097:blood*
D001786:Blood Glucose; D003277:Contraceptives, Oral, Combined; D005230:Fatty Acids, Nonesterified; D007328:Insulin; D007659:Ketones; D005990:Glycerol