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A three-year evaluation of metabolic changes in Singaporean Norplant acceptors

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Abstract

In a longitudinal study involving 100 Singaporean women, the effect of NorplantR on metabolic function was evaluated. With respect to liver function, the results indicate possible hepatocellular dysfunction as evidenced by a significant rise in serum bilirubin and a significant fall in total proteins and globulin during the period under review.

As regards lipid metabolism, total triglycerides and total cholesterol still remained significantly decreased at the end of the three years. The LDL, which was significantly decreased in the first year, increased during the subsequent two years to its preinsertion value at the end of three years. The HDL-cholesterol levels continued to decrease in the second and third year after a significant increase in the first year. Despite this, the HDL cholesterol/total cholesterol-HDL cholesterol remained above 0.200. As we have not incorporated a simultaneous non-pill treated control group, the observed changes in lipoprotein lipids could be attributed to extraneous factors such as diet, exercise, or other environmental changes. Nevertheless, the findings at the end of three years, though speculative, still appear to indicate Norplant use to be not directly contributory to cardiovascular risk.

The use of Norplant was not associated with any significant effects on carbohydrate metabolism after three years of use.

Resumé

On a évalué dans une étude longitudinale portant sur 100 femmes singapouriennes les effets de Norplant sur la fonction métabolique. En ce qui concerne la fonction hépatique, les résultats indiquent des troubles hépatocellulaires possibles, mis en évidence par une élévation significative de la bilirubine sérique et une diminution significative des protéines totales et de la globuline pendant la période étudiée.

Quant au métabolisme des lipides, les totaux des triglycérides et du cholestérol étaient encore abaissés de façon significative au terme de la période de trois ans. Les lipoprotéines légères, qui avaient considérablement diminué pendant la première année, sont remontées pendant les deux années suivantes pour retrouver, à la fin de la troisième année, le niveau qu'elles avaient avant l'insertion. Les niveaux de cholestérol HDL (lipoprotéines lourdes) ont continué à baisser pendant les deuxième et troisième années après une élévation significative pendant le première. Malgré cela, le rapport cholestérol HDL/Cholestérol total-cholestérol HDL est resté supérieur à 0.200. N'ayant pas inclus un groupe témoin sans pillule traité simultanément, les changements observés concernant les lipides lipoprotéiniques pourraient être attribués à des facteurs extérieurs tels que le régime alimentaire, l'activité physique ou d'autres facteurs d'environnement. Néanmoins, bien que de caractère conjectural, les constatations résultant de ces trois ans d'étude semblent encore indiquer que l'utilisation de Norplant ne contribue pas directement au risque cardiovasculaire. L'utilisation de Norplant n'a été liée à aucun effet significatif sur le métabolisme des hydrates de carbone au bout de trois ans.

Resumen

En un estudio longitudinal sobre 100 mujeres de Singapur se evaluaron los efectos de Norplant sobre la función metabólica. En lo que respecta a la función hepática, los resultados indican posibles trastornos hepatocelulares, señalados por una elevación significantiva de la bilirrubina sérica y una disminución significativa de las proteínas totales y de la globulina durante el período estudiado.

En lo que respecta al metabolismo de los lípidos, los totales de triglicéridos y de colesterol continuaban significativamente disminuidos al cabo del período de tres años. Las lipoproteínas ligeras, que habían disminuido considerablement durante el primer año, aumentaron durante los dos años siguientes, alcanzando, al final del tercer año, el nivel que habían señalado antes de la inserción. Los niveles de colesterol HDL (lipoproteínas pesadas) continuaron disminuyendo en el segundo y tercer año después de un aumento significativo durante el primer año. A pesar de ello, la relación colesterol HDL/colesterol total-colesterol HDL continuó siendo superior a 0.200. Dado que no se incluyó un grupo control sin píldora tratado simultáneamente, los cambios observados respecto de los lípidos lipoproteínicos podrían atribuirse a factores exteriores, tales como el régimen alimentario, la actividad física u otros factores ambientales. No obstante, a pesar de su carácter conjetural, los resultados de este estudio de tres años parecen indicar que el uso de Norplant no contribuye directamente al riesgo cardiovascular.

El uso de Norplant no estuvo asociado con ningún efecto significativo sobre el metabolismo de los hidratos de carbono al cabo de tres años.

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References

  1. 1.

    MillerG.J. and MillerN.E. (1975). Plasma high density lipoprotein concentration and development of ischaemic heart disease.Lancet,1, 16

  2. 2.

    BaggetB. and NashH.A., (1980). Effects of contraceptive steroids on serum lipoproteins and cardiovascular disease.Contraception,21, 115

  3. 3.

    CastelliW.P., DoyleJ.T., GordonT., HamesC.G., HjortlandM.C., HulleyS.B., KaganA. and ZukelW.J. (1977). HDL cholesterol and other lipids in coronary heart disease.Circulation,55, 767–772

  4. 4.

    GordonT., CastellW.P., HjortlandM.C., KannelW.B. and DawberT.R. (1977). High density lipoprotein as a protective factor against coronary heart disease.Am. J. Med.,62, 707–714

  5. 5.

    BradleyD.D., WingredJ., PetittiD.B., KraussR.M. and RamcharanS. (1978). Serum high density lipoprotein cholesterol in women using oral contraceptives, estrogens and progestins.N. Engl. J. Med.,299, 17–20

  6. 6.

    BriggsM. and BriggsM. (1981). A randomised study of metabolic effects of four low-estrogen oral contraceptives: I. Results after 6 cycles.Contraception,23, 463

  7. 7.

    KnoppR.H., WaldenC.E., WahlP.W. and HooverJ.J. (1982). Effect of oral contraceptives on lipoprotein, triglycerides and cholesterol: relationship to estrogen and progestin therapy.Am. J. Obstet. Gynecol.,142, 725

  8. 8.

    WynnV. and NiththyananthanR. (1982). The effects of progestins in combined oral contraceptives on serum lipids with special reference to high density lipoproteins.Am. J. Obstet. Gynecol.,142, 766

  9. 9.

    CrampD.G. (1967). New automated method for measuring glucose by glucose oxidase.J. Clin. Pathol.,20, 910–912

  10. 10.

    WeichselbaumT.E. (1946). An accurate and rapid method for the determination of proteins in small amounts of blood serum and plasma.Am. J. Clin. Pathol.,16, 40–49

  11. 11.

    SpencerK. and PriceC.P. (1977). Influence of reagent quality and reaction conditions on the determination of serum albumin by the Bromocresol Green-Dye Binding Method.Ann. Clin. Biochem.,14, 105–115

  12. 12.

    JendrassikL. and GrofP. (1938). Simplified photometric methods for the determination of the blood bilirubin.Biochem. Z.,297, 81–89

  13. 13.

    BesseyF.K., LowryO.H. and BrockM.J. (1946). A method for the rapid determination of alkaline phosphatase with five cubic millimetres of serum.J. Biol. Chem.,164, 321–329

  14. 14.

    BursteinM., ScholnikH.R. and MorfinR. (1970). Rapid method for the isolation of lipoproteins for human serum by precipitation with polyanions.J. Lipid Res.,11, 583–595

  15. 15.

    TrinderP. (1969). Determination of glucose in blood using glucose oxidase with an alternative oxygen acceptor.Ann. Clin. Biochem.,6, 24–27

  16. 16.

    StahlerF., GruberW. and StinohoffK. (1977). Eine praxisgerechte enzymatic Cholesterinbestimmung.Med. Lab. (Stuttg.),30, 29–37

  17. 17.

    WahfieldA.W. (1974). Methods of enzymatic analysis. In: BergmeyerH.U. ed., Verlag Chemiw Weinheim and Academic Press, New York and London, pp. 1831

  18. 18.

    FriedewaldW.I., LevyR.I. and FredricksonD.S. (1982). Estimation of the concentration of low density lipoprotein cholesterol in plasma, without use of the preparative ultracentrifuge.Clin. Chem.,18, 499–502

  19. 19.

    CroxattoH.B., DiazS. and PavezM. (1978). Clinical chemistry in women treated with progestogen implants.Contraception,18, 441–450

  20. 20.

    CroxattoH.D., DiazS., RobertsonD.N. and PavezM. (1983). Clinical chemistry in women treated with levonorgestrel implants (Norplant) or TCu-200-IUD.Contraception,27, 281–288

  21. 21.

    ShaabanM.M., ElwanS.I., El-SharkawyM.M. and FarghalyA.S. (1984). Effect of levonorgestrel contraceptive implants (Norplant) on liver function.Contraception,30, 407–412

  22. 22.

    SinghK., ViegasO., LiewD., SinghP. and RatnamS.S. (1988). The effects of Norplant on clinical chemistry in Singapore acceptors after one year of use: metabolic changes.Contraception,38, 79–89

  23. 23.

    RobertsonD.N. (1983). Norgestrel releasing silastic rods: clinical effects, biochemical effects and in vivo release rates. In:Advances in Human Fertility and Reproductive Endocrinology, Vol. 2. Long-acting Steroid Contraception, D.R.MischellJr., ed., Raven Press, New York, pp. 127–147

  24. 24.

    ShaabanM.M., AbdallaS.I., AnchS.A. and DarwishH.A. (1984). Effects of subdermal levonorgestrel contraceptive implants, norplant, on serum lipids.Contraception,30, 413–419

  25. 25.

    HolmaP. and RobertsonD.N. (1985). Cholesterol and HDL-cholesterol values in human during use of subdermal implants releasing levonorgestrel.Contraception,32 (2), 163–171

  26. 26.

    HjermanI., Velve ByreK., HolmeI. and LerenP. (1981). Effect of diet and smoking intervention on the incidence of coronary heart disease.Lancet,2, 1303–1310

  27. 27.

    NikkilaE.A., ViikinkoskiP., ValleM. and FrickM.H. (1984). Prevention of progression of coronary atherosclerosis by treatment of hyperlipidaemia: a seven year prospective angiographic study.Br. Med. J.,289, 220–223

  28. 28.

    Singh, K., Viegas, O., Liew, D., Singh, P. and Ratnam, S.S. (1989). Two-year follow-up of changes in clinical chemistry in Singaporean Norplant acceptors: metabolic changes.Contraception (in press)

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Singh, K., Viegas, O.A.C. & Ratnam, S.S. A three-year evaluation of metabolic changes in Singaporean Norplant acceptors. Adv Contracept 6, 11–21 (1990). https://doi.org/10.1007/BF01849483

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Keywords

  • Bilirubin
  • Avant
  • Carbohydrate Metabolism
  • Serum Bilirubin
  • Metabolic Function