Digitized assessment of mammographic breast density--effects of continuous combined hormone therapy, tibolone and black cohosh compared to placebo.

OBJECTIVES: To determine the effects of continuous combined hormone therapy, tibolone, black cohosh, and placebo on digitized mammographic breast density in postmenopausal women. STUDY DESIGN: A prospective, double-blind, placebo-controlled study of 154 postmenopausal women randomized to estradiol 2 mg/norethisterone acetate 1 mg (E2/NETA), tibolone 2.5 mg or placebo and a prospective, open, uncontrolled drug safety study, of which 65 postmenopausal women were treated with black cohosh. Mammograms, at baseline and after six months of treatment, were previously classified according to visual quantification scales. MAIN OUTCOME MEASURES: Reanalysis of assessable mammograms by digitized quantification of breast density. RESULTS: Treatment groups were comparable at baseline. During treatment, both E2/NETA and tibolone significantly increased breast density (mean increase 14.3%, p<0.001 and 2.3%, p<0.001, respectively), while black cohosh and placebo did not. Twenty-four out of the 43 women on E2/NETA had an increase in density exceeding 10% and 6 women had an increase of 30% or more. In the tibolone group, only one woman had an increase in density of more than 10%. The difference in increase in breast density between E2/NETA on the one hand and tibolone, black cohosh and placebo on the other was highly significant (p<0.0001). CONCLUSIONS: Digitized mammographic breast density is a highly sensitive method confirming significant increase in density by standard E2/NETA treatment and to a lesser extent by tibolone, whereas black cohosh does not influence mammographic breast density during six months treatment. Digitized assessment also yields data on individual variation and small increases left undetectable by visual classification.

In vitro molecular assessment of the mechanisms of action of 19-nor progestins used as contragestational agents.

Norethisterone (NET) and levonorgestrel (LNG) are synthetic progestins used as contragestational agents. Both compounds are biotransformed at target tissues into A-ring reduced metabolites which possess different pharmacological properties. The aim of this study was to determine the molecular mechanisms of the progestational and antiprogestational effects of NET, LNG and their metabolites by using a highly efficient, sensitive in vitro molecular assay based on the detection of a reporter gene expression (the bacterial chloramphenicol acetyltransferase (CAT) inserted downstream of a minimal promoter containing two progesterone responsive elements (PRE2) and the TATA box. For this purpose we used CV-1 monkey kidney cells, which do not possess steroid receptors. These cells were cotransfected with a progesterone receptor expression vector and the reporter vector PRE2-TATA-CAT. Data obtained using this model showed that NET and LNG induced CAT activity in a manner similar to that of the potent progestin R5020. NET and LNG metabolites exhibited a weak progestational activity; however, when 5 alpha-NET metabolite was simultaneously administered with R5020, a clear antiprogestational effect similar to that of the antiprogestin RU486 was observed. Therefore, the results clearly demonstrate that the use of the reporter CAT vector containing hormone responsive elements is a suitable assay for the screening and evaluation of new synthetic steroids with agonist or antagonist progestational activities in transfected CV-1 cell line.

Comparative assessment of two low-dose oral contraceptives, Lo-Femenal and Lo-Estrin, in Mexican women.

This trial was designed to determine the differences in effectiveness, clinical acceptability, and one-year discontinuation rates of two low-dose oral contraceptives: Lo-Estrin (norethindrone acetate 1.5 mg plus ethinyl estradiol 0.030 mg) and Lo-Femenal (norgestrel 0.30 mg plus ethinyl estradiol 0.030 mg) in 148 Mexican women. In addition, the effects of both oral contraceptive preparations on blood lipids were prospectively evaluated in a subgroup of 41 women. The results indicated that there were no differences in pregnancy rates, discontinuation or clinical acceptability between the two groups. The lipid changes observed were minimal for the Lo-Femenal subgroup and somewhat greater for the Lo-Estrin group, mainly an increase in serum triglycerides. These changes were interpreted as estrogen induced effects of norethindrone-containing oral contraceptives. Overall, the data indicate that both Lo-Femenal and Lo-Estrin are effective and safe combined oral contraceptives.

Assessment of a new low-dose once-a-month injectable contraceptive.

Norethisterone (NET) in combination with mestranol (ME), in a macrocrystalline aqueous suspension that provides sustained release of steroids, was assessed as a once-a-month injectable contraceptive in ten healthy women of reproductive age. The ovarian function was studied before and after the intramuscular administration of 12mg NET plus 1.2mg ME, delivered as crystals of 150 micron average size. Serial blood samples were taken throughout the injection intervals in all women to measure serum progesterone (P), estradiol (E2), and NET. The NET/ME preparation effectively inhibited ovulation in 23 out of the 25 injection intervals studied. The administration of this formulation induced in some women a small degree of follicular maturation not followed by luteal activity. The endometrial bleeding patterns after each injection showed a bleeding-free period of two to three weeks. The overall data demonstrate that the parenteral administration of a macrocrystalline steroid preparation of NET/ME can bring about a sustained release contraceptive system at a substantially lower dose than those currently employed in once-a-month injectable contraception.

Assessment of the potency of orally administered progestins in women.

The effects of at least three doses of each of five orally administered progestins on estrogen-primed, postmenopausal endometrial biochemistry and morphologic features were analyzed. The progestins tested were norethindrone, medroxyprogesterone acetate (MPA), norgestrel, dydrogesterone, and progesterone. The dose required to elicit responses similar to those seen in premenopausal, secretory endometria was assessed for each of the parameters measured, and the relative potencies were calculated. Potencies, relative to a value of 1 for norethindrone, are L norgestrel 8 (D/L norgestrel 4), MPA 0.1, dydrogesterone 0.02, and progesterone 0.002. The dose of norethindrone required to elicit secretory phase activity was about 0.35 mg/day. These values agree with published data obtained with the use of different methods (delay of menstruation in premenopausal women, endometrial histologic features of estrogen-primed, ovariectomized women).

An assessment of the side effects of switching from one oral contraceptive to another.

Side effects associated with three oral contraceptives were evaluated in a study in which women were switched to Norlestrin 1 from either Ovral (64 subjects) or Norinyl 1/50 (26 subjects). In the cycle prior to crossover, breast discomfort was more frequent among Norinyl users than among Ovral users. The prevalence of all other reported side effects was not significantly different for Norinyl and Ovral. The crossover to Norlestrin did not significantly change the numbers of patients reporting side effects. By the end of third Norlestrin cycle, rates of all side effects were similar for women who were switched from either Ovral or Norinyl.

Effect of oral contraceptive agents on nutrients: II. Vitamins.

Clinical, biochemical and nutritional data were collected from a large population of women using oral contraceptive agents. Higher incidence of abnormal clinical signs related to malnutrition were observed in the lower (B) as compared to the higher (A) socioeconomic groups, and also in the nonsupplemented groups as compared to the supplemented groups in the B subjects. As a rule the intake of oral contraceptive agent subjects of vitamin A, C, B6 and folic acid did not differ from that of the controls As expected, subjects from the supplemented groups had higher intake of vitamin A, C, B6, thiamin, riboflavin and folic acid, and A groups had higher intake of vitamin C, B6, riboflavin and folic acid. Increased plasma vitamin A and decreased carotene levels were observed in oral contraceptive agent users. In general oral contraceptive agents had little or no effect on plasma ascorbic acid. Urinary excretion of both thiamin and riboflavin in subjects using oral contraceptive agents were lower in A groups. Erythrocyte folate and plasma pyridoxal phosphate was decreased in A groups due to oral contraceptive agents. Subjects who took supplements had higher levels of plasma vitamin A, ascorbic acid and folate. But urinary thiamin and riboflavin were higher only in group A subjects who took supplements.

PIP: 18-45 year old women were tested to determine if the use of oral contraceptive agents (OCAs) affects the metabolism of vitamins. 4 different hormonal conditions and 2 socioeconomic levels in 8 groups were considered. Some of each socioeconomic level had taken Norinyl (1 mg norethisterone and 50 mcg mestranol) for 3 months or more. Others had used Ovral (.5 mg norgestrel and 5 mcg ethinyl estradiol) for equal periods. There were some in each group who had resumed use of OCAs during lactation within 5 weeks after pregnancy. Vitamins and mineral supplements were given to groups in each socioeconomic classification. They had a higher intake of Vitamins-A, C, thiamin, riboflavin, and folic acid. Incidence of clinical sings of malnutrition, such as dry skin, easily pluckable hair, angular lesions of the mouth, dental caries, bleeding gums, glossitis, and scaling of the skin, were significantly more frequently observed in the lower socioeconomic groups, and especially in nonsupplemented groups of women taking OCAs than in others. OCA administration increased plasma Vitamin-A levels but no socioeconomic effect was found. Plasma carotene levels were decreased by OCA therapy, but less so in the higher socioeconomic subjects. Plasma ascorbate was not affected by OCA use. Urinary excretion of thiamin annd riboflavin was decreased in subjects using OCAs. Erythrocyte folate and plasma pyridoxal phosphate (PLP) were also decreased. Results show a definite lowering effect of OCAs on red cell folate in subjects in the upper socioeconomic levels. There may also be a depletion of body stores of folic acid. It has been suggested that women who become pregnant soon after discontinuing OCA therapy have a high chance of developing folic acid deficiency during pregnancy. The lower socioeconomic group may be marginally deficient in folic acid. Similar results were obtained with thiamin and riboflavin. Changes due to OCA use with respect to thiamin, riboflavin, folate, and PLP were seen mainly in subjects in the upper lower socioeconomic groups may have prevented detection of smaller similar alterations due to OCA use.

Effect of oral contraceptive agents on nutrients: I. Minerals.

The epidemiological aspects of oral contraceptive agents on nutrient metabolism were studied in a large population of women. Incidence of clinical abnormalities, related to malnutrition, were more frequently observed in the lower (B) as compared to the higher (A) socioeconomic groups. In the A groups some clinical signs were more common in the nonsupplemented groups of subjects. In general, the intake of oral contraceptive agent subjects for calories, protein, calcium, magnesium, iron, copper and zinc did not differ from the controls. The intake of the above nutrients in group A subjects were higher than those of group B except for calories. The subjects who took supplements had higher intakes of calcium, iron, magnesium and copper. No effect of oral contraceptive agents was seen on hemoglobin, hematocrit and erythrocyte count. Serum iron was increased due to "Norinyl." Total iron binding capacity was increased as a result of oral contraceptive agent administration. Total iron binding capacity values were higher in group B as compared to group A and in the nonsupplemented as compared to the supplemented groups. Plasma copper was increased and plasma zinc was decreased as a result of oral contraceptive agent administration. An increase in erythrocyte zinc was observed due to "Norinyl." No effect of oral contraceptive agents on plasma calcium, magnesium and erythrocyte magnesium was observed. Although no effect of oral contraceptive agents on plasma total protein was found, serum albumin was decreased.