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Biomedical subjects

I Persson

Publications and source records attributed to I Persson.

At least 19 recordsLinked to original sources
PubMed1999

Risk of endometrial cancer following estrogen replacement with and without progestins.

BACKGROUND: Unopposed estrogen replacement therapy (i.e., estrogen without progestins) increases the risk of endometrial cancer. In this study, we examined the endometrial cancer risk associated with combined estrogen-progestin regimens currently in use, since the safety profiles of these regimens have not been clearly defined. METHODS: We conducted a nationwide population-based, case-control study in Sweden of postmenopausal women aged 50-74 years. We collected information on use of hormone replacement from 709 case patients with incident endometrial cancer and from 3368 control subjects. We used unconditional logistic regression to calculate odds ratios (ORs) as estimates of relative risks. All individual comparisons were made with women who never used the respective hormone replacement regimens. RESULTS: Treatment with estrogens alone was associated with a marked duration- and dose-dependent increase in the relative risk of endometrial cancer. Five or more years of treatment had an OR of 6.2 for estradiol (95% confidence interval [CI] = 3.1-12.6) and of 6.6 for conjugated estrogens (95% CI = 3.6-12.0). Following combined estrogen-progestin use, the association was considerably weaker than that for estrogen alone; the OR was 1.6 (95% CI = 1.1-2.4) after 5 or more years of use. This increase in risk was confined to women with cyclic use of progestins, i.e., fewer than 16 days per cycle (most commonly 10 days per cycle [OR = 2.9; 95% CI = 1.8-4.6 for 5 or more years of use]), whereas continuous progestin use along with estrogens was associated with a reduced risk (OR = 0.2; 95% CI = 0.1-0.8 for 5 or more years of use). CONCLUSION: The risk of developing endometrial cancer is increased after long-term use of estrogens without progestins and with cyclically added progestins. Continuously added progestins may be needed to minimize the endometrial cancer risk associated with estrogen replacement therapy.

Adenocarcinoma↗
PubMed1999

Low-potency oestrogen and risk of endometrial cancer: a case-control study.

BACKGROUND: Urogenital symptoms are common among postmenopausal women. Such symptoms may be alleviated by low-potency oestrogen formulations administered orally or vaginally. Although low-potency oestrogen formulations are assumed to have few, if any, adverse effects on the endometrium, risk of endometrial neoplasia has not been quantified. METHODS: In a nationwide population-based case-control study in Sweden of endometrial cancer among postmenopausal women, we obtained detailed information on hormone replacement from 789 cases of endometrial cancer and 3368 population controls. In a histopathological review, 80 cases were reclassified as having endometrial atypical hyperplasia. Odds ratios and 95% CI were calculated with unconditional logistic regression. FINDINGS: After multivariate adjustment, oral use of oestriol 1-2 mg daily increased the relative risk of endometrial cancer and endometrial atypical hyperplasia: the odds ratios for at least 5 years of use compared with never use were 3.0 (95% CI 2.0-4.4) and 8.3 (4.0-17.4), respectively. The association was stronger for well-differentiated cancers and those with limited invasion. The excess relative risk was lost rapidly after cessation of treatment. Only weak associations were observed between vaginal application of low-potency oestrogen formulations and relative risk of endometrial neoplasia. INTERPRETATION: Oral, but not vaginal, treatment with low-potency oestrogen formulations increases the relative risk of endometrial neoplasia. Thus close surveillance of patients is needed, and addition of a progestagen should be considered.

Administration, Intravaginal↗
PubMed1999

Genetic polymorphism of xenobiotic metabolizing enzymes among Chinese lung cancer patients.

Polymorphisms in xenobiotic metabolizing enzymes have been implicated in inter-individual and inter-ethnic differences in cancer susceptibilty. Several studies have indicated an association between variant alleles of the human CYP1A1, CYP2E1 and GSTM1 genes and lung cancer. Activity of microsomal epoxide hydrolase (HYL1) has also been associated with lung cancer, and 2 variant alleles causing amino acid substitutions have been described. We have investigated genetic polymorphisms of the CYP1A1, CYP2E1, GSTM1 and HYL1 genes in 76 Chinese lung cancer patients and 122 healthy Chinese subjects. The allele frequency of the CYP1A1*2B allele was 0.21 among lung cancer patients and 0.20 in the reference group, whereas the corresponding values for the CYP1A1*2A allele were 0.34 and 0.36. The CYP2E1*5B and CYP2E1*6 alleles were less frequent among the cancer patients (0.20 and 0.22) compared with healthy subjects (0.25 and 0.26). The frequency distribution of the HYL1*2 allele was 0.49 among lung cancer patients and 0.42 in the reference group, and the corresponding frequencies for the HYL1*3 allele were 0.13 and 0.10. The homozygous GSTM1*0 genotype was found in 64% of lung cancer patients and in 66% of healthy subjects. Among heavy smokers, the frequency was 73%. The differences in the distribution of variant CYP1A1, CYP2E1 and GSTM1 alleles in lung cancer patients and healthy controls were not statistically significant. Our results indicate that the polymorphisms investigated are of minor importance as genetic susceptibility markers for lung cancer in this population. An increased risk for lung cancer in subjects carrying the HYL*3 allele was observed and suggests that polymorphism in this gene might possibly be a susceptibility factor in the Chinese population.

Adult↗
PubMed1999

Breast-cancer risk following long-term oestrogen- and oestrogen-progestin-replacement therapy.

While use of hormone-replacement therapy (HRT) effectively alleviates menopausal symptoms and prevents osteoporosis and possibly cardiovascular disease, there is concern of a detrimental impact on breast-cancer risk. There is a particular lack of data regarding the effect of long-term use of oestrogen-progestin combinations on breast-cancer risk. We conducted a large epidemiological study in Sweden, where combined oestrogen-progestin treatment has been predominant, to examine the influence of different regimens of menopausal hormone therapy on breast-cancer risk. In this population-based case-control study, 3,345 women aged 50 to 74 years with invasive breast cancer (84% of all eligible) and 3,454 controls of similar age (82% of all selected) were included. Mailed questionnaires and telephone interviews were used to collect detailed information on use of hormone replacement and on potential confounding factors. Odds ratios (OR) and 95% confidence intervals (CI) were estimated through multiple logistic regression. There was a trend of increasing breast-cancer risk with duration of oestrogen/oestrogen-progestin use (OR for women treated at least 10 years, 2.43; 95% CI, 1.79-3.30, as compared to never-users), with statistically significant estimates only for women with BMI<27 kg/m2. Excess risks were observed to current use and use that ceased more than 10 years ago (OR for women treated at least 5 years, OR was 2.68, 95% CI, 2.09-3.42, and OR 2.57, 95% CI, 1.28-5.15, as compared with never-users, respectively). A positive association which was noted for use of oestrogen combined with testosterone-derived progestins appeared especially pronounced with continuously combined regimens. Long-term use of replacement oestrogens with or without progestins may substantially increase the incidence of post-menopausal breast cancer, particularly among non-obese women.

Breast Neoplasms↗
PubMed1999

Oral-contraceptive use and risk of hip fracture: a case-control study.

BACKGROUND: Epidemiological studies indicate a protective effect of postmenopausal oestrogen therapy on the risk of osteoporotic fractures. Whether premenopausal oestrogen exposure in the form of oral contraceptives also reduces the risk of osteoporotic fractures remains uncertain. METHOD: We did a population-based case control study of hip fracture among Swedish postmenopausal women, 50-81 years of age, through mailed questionnaires and telephone interviews. Of those women who were eligible, 1327 (82.5%) cases and 3312 (81.6%) randomly selected controls responded. FINDINGS: 130 (11.6%) cases and 562 (19.1%) controls reported ever-use of oral contraceptives. Ever-use of oral contraceptives was associated with a 25% reduction in hip fracture risk (odds ratio 0.75 [95% CI 0.59-0.96]). Women who had ever used a high-dose pill (equivalent to > or = 50 microg ethinylestradiol per tablet) had a 44% lower risk for hip fracture than never-users (0.56 [0.42-0.75]). No overall trend was observed with duration of oral-contraceptive use, or time since last use. However, when making comparisons with women who have never used oral contraceptives, the odds ratios for hip-fracture were 0.69 (0.51-0.94) for use after age 40, 0.82 (0.57-1.16) for use at ages 30-39, and 1.26 (0.76-2.09) for use before age 30. INTERPRETATION: Our results imply that in postmenopausal women, oral-contraceptive use late in reproductive life may reduce the risk of hip fracture, although we recognise the limitations of the case-control method.

Adult↗
PubMed1999

Performance in functional balance tests during menopausal hormone replacement: a double-blind placebo-controlled study.

BACKGROUND AND PURPOSE: Recent studies have indicated that oestrogens might have an effect on postural control. The purpose of this study was to investigate the short-term effect of hormone replacement therapy (HRT) on postural control in menopausal women and to analyse the correlation between sway velocity measures and results of functional balance tests. SUBJECTS: 100 menopausal women who were randomized to receive either HRT or placebo for three months were included in the study. METHOD: The balance function was measured with nine different static and dynamic functional balance tests. The sway velocities were measured on a computerized force platform. RESULTS: No significant differences were found between the two groups in the results of the functional balance tests after the three-month placebo-controlled period or in the changes over time. However, some significant improvements occurred within both groups over this three-month period. The correlations between different sway velocities and the results of the functional balance tests were all very low (r < 0.35). CONCLUSION: It can not be concluded that HRT had a positive effect on the performance in the functional balance tests, as some improvement occurred in both groups. The low correlations indicate that the sway velocity and functional balance tests measure different aspects of balance function.

Analysis of Variance↗
PubMed1999

Nest attendance during egg laying in pheasants.

As precocial bird species hatch synchronously, incubation during the egg-laying stage should be disadvantageous because it makes the embryos develop asynchronously. We established the patterns of nest attendance during egg laying and the start of incubation in ring-necked pheasants, Phasianus colchicus, and tested three hypotheses regarding the advantage of early incubation. To determine nest attendance, we measured egg temperatures in real pheasant nests. Females spent more time on the nest as laying progressed, with an average of 6.4 h at a clutch size of 10. At the start of incubation, nest attendance increased to over 20 h/day. On the day before full incubation, time spent on the nest was positively correlated with the female's condition and negatively with the number of breeding attempts she had already made that season. The hypothesis that an early start of incubation improves egg viability was rejected, as the predicted relationship between the number of eggs laid after the start of incubation and the number laid before the start of incubation was not significant. We also rejected the possibility that early incubation reduces the risk of nest parasitism, as it was negatively related to the number of females radiotracked around the nest. Our data supported the hypothesis that early incubation reduces the risk of nest predation by shortening the period of exposure, as the number of eggs laid after incubation started was positively related to the number of breeding attempts made by the female, and thus to the perceived predation risk, but was negatively related to the time of season. Copyright 1999 The Association for the Study of Animal Behaviour.

Journal Article↗
PubMed1999

Equality and selection for existence.

It is argued that the policy of excluding from further life some human gametes and pre-embryos as "unfit" for existence is not at odds with a defensible idea of human equality. Such an idea must be compatible with the obvious fact that the "functional" value of humans differs, that their "use" to themselves and others differs. A defensible idea of human equality is instead grounded in the fact that as this functional difference is genetically determined, it is nothing which makes humans deserve or be worthy of being better or worse off. Rather, nobody is worth a better life than anyone else. This idea of equality is, however, not applicable to gametes and pre-embryos, since they are not human beings, but something out of which human beings develop.

Beginning of Human Life↗
PubMed1999

Ultrasonographic blood flow measurement in the carotid arteries in postmenopausal women.

OBJECTIVES: The aim of the present study was to evaluate blood flow in postmenopausal women on hormone replacement therapy (HRT) compared to controls. Blood flow was ultrasonographically measured in the great arteries of the neck instead of in the vessels of the internal genital organs. METHODS: Fifty healthy women with climacteric complaints, at least 6 months postmenopausal, participated in the study. They were randomly divided into two groups. One group received 2 mg estradiol (E2) for 12 days, continued with 2 mg E2 and 1 mg norethisterone acetate for 10 days, followed by 1 mg E2 for 6 days, cyclically during 6 months. The other group received placebo tablets the first 3 months and the same HRT as the first group for the last 3 months. Blood flow was measured ultrasonographically by color flow pulsed Doppler in the common (CCA), internal (ICA) and external (ECA) carotid arteries, before the start of the study, after 3 and 6 months of therapy. RESULTS: CCA and ICA, both low resistance vessels, and ECA, a high resistance vessel, and their waveforms were identified. Pulsatility index did not decrease statistically significant (p > 0.05) in any of the great vessels during 6 months of HRT in this study. There were no differences in blood flow between the HRT-treated group compared to control group during 3 months of therapy, except for the right ECA (p = 0.04). CONCLUSION: The difference in blood flow and wave-forms of the major arteries of the neck were clearly shown, but HRT did not have any important impact on the blood flow in this study. No difference was shown concerning blood flow between the two groups of postmenopausal women, on active therapy or placebo.

Carotid Arteries↗
PubMed1999

Postmenopausal hormone therapy and risk of cardiovascular disease and hip fracture in a cohort of Swedish women.

Postmenopausal estrogen use is associated with a reduced risk of heart disease and hip fracture; in observational studies, different behaviors among hormone users and nonusers may partially explain these results. We examined risk of cardiovascular disease and hip fracture with medium-potency compared with low-potency or short-term estrogen use, and the effect of added progestin, among 9,236 women in Uppsala, Sweden, who responded to a mailed questionnaire in 1987-1988. Using population registries, we identified 213 cases of myocardial infarction, 289 strokes, and 114 hip fractures from 1987-1995. We found a reduced risk of myocardial infarction for medium-potency compared with low-potency or short-term estrogen use (relative risk = 0.75, 95% confidence interval (CI) = 0.56-0.99), with a similar decrease in the subgroup that took estrogens with progestin (RR = 0.69, 95% CI = 0.45-0.90). There was no relation of medium-potency estrogen to stroke (RR = 0.91, 95% CI = 0.71-1.17, and RR = 0.81, 95% CI = 0.61-1.10 for the subgroup taking progestin), and no effect of duration on either heart disease or stroke. We observed a reduction in hip fractures for medium-potency use (RR = 0.65, 95% CI = 0.45-0.95), and for use of combined estrogen-progestin therapy (RR = 0.64, 95% CI = 0.41-1.00). These data support a decreased risk of heart disease and hip fracture for medium-potency estrogen use alone or with progestin; self-selection to hormone use cannot explain these reductions.

Cardiovascular Diseases↗
PubMed1998

Hormone replacement therapy and risk of hip fracture: population based case-control study. The Swedish Hip Fracture Study Group.

OBJECTIVE: To determine the relative risk of hip fracture associated with postmenopausal hormone replacement therapy including the effect of duration and recency of treatment, the addition of progestins, route of administration, and dose. DESIGN: Population based case-control study. SETTING: Six counties in Sweden. SUBJECTS: 1327 women aged 50-81 years with hip fracture and 3262 randomly selected controls. MAIN OUTCOME MEASURE: Use of hormone replacement therapy. RESULTS: Compared with women who had never used hormone replacement therapy, current users had an odds ratio of 0.35 (95 % confidence interval 0.24 to 0.53) for hip fracture and former users had an odds ratio of 0.76 (0.57 to 1.01). For every year of therapy, the overall risk decreased by 6% (3% to 9%): 4% (1% to 8%) for regimens without progestin and 11% (6% to 16%) for those with progestin. Last use between one and five years previously, with a duration of use more than five years, was associated with an odds ratio of 0.27 (0.08 to 0.94). After five years without hormone replacement therapy the protective effect was substantially diminished (-7% to 48%). With current use, an initiation of therapy nine or more years after the menopause gave equally strong reduction in risk for hip fracture as an earlier start. Oestrogen treatment with skin patches gave similar risk estimates as oral regimens. CONCLUSIONS: Recent use of hormone replacement therapy is required for optimum fracture protection, but therapy can be started several years after the menopause. The protective effect increases with duration of use, and an oestrogen-sparing effect is achieved when progestins are included in the regimen.

Administration, Cutaneous↗
PubMed1998

Body size in different periods of life and breast cancer risk in post-menopausal women.

Adult obesity has been associated with an increased risk of post-menopausal breast cancer, but it is unclear whether this relationship reflects a causal role of obesity during childhood and adolescence, of weight gain during adult life or of adult obesity per se. In a population-based case-control study in all of Sweden, we included 3,345 (84% of all eligible) women aged 50-74 years with invasive breast cancer, and 3,454 (82% of all selected) controls of similar age. Mailed questionnaires and telephone interviews were used to collect detailed information on anthropometric measures. Odds ratios were estimated through multiple logistic regression. Women with the leanest somatotype at age 7 had about a 3-fold higher risk of breast cancer than the most obese (P for trend 0.0009). A suggested protective effect of a high body mass at age 18 and a detrimental influence of body mass 1 year prior to data collection largely reflected the effect of weight gain after age 18, a strong predictor of breast cancer risk. Among women at least 20 years post menopause, those who had gained 30 kg or more since age 18 had an odds ratio of 2.04 (95% confidence interval 1.20-3.48) of breast cancer compared with those who had maintained their weight unchanged. The effect of weight gain was unequivocal among non-users but not among users of hormone replacement therapy. Our findings have important implications, suggesting weight preservation as a means for prevention of post-menopausal breast cancer as well as a causal role of childhood body build in breast cancer etiology.

Age Factors↗
PubMed1998

Variation in the efficacy of hormone replacement therapy in the prevention of hip fracture. Swedish Hip Fracture Study Group.

Use of postmenopausal hormone replacement therapy (HRT) has been associated with a reduced risk of osteoporotic fractures. However, it is uncertain whether this risk reduction is modified by other risk factors for hip fracture. In a population-based case-control study in Sweden, we investigated the association between HRT and hip fracture risk within categories of age, body measures and lifestyle factors in postmenopausal women, 50-81 years of age. Mailed questionnaires and telephone interviews were used to collect data. Of those eligible, 1328 incident cases with hip fracture (82.5%) and 3312 randomly selected controls (81.6%) answered the questionnaire. Ever use of HRT in women less than 75 years old was associated with an odds ratio (OR) of 0.66 (95% confidence interval: 95% CI 0.50-0.87) for hip fracture compared with OR 0.40 (95% CI 0.21-0.77) in women 75 years or older. We found a significant interaction between HRT and both weight and physical activity (p < 0.05). The protective effect of HRT was particularly pronounced in lean women: compared with never HRT users, ever users weighing under 60 kg had an OR of 0.44 (95% CI 0.30-0.66) whereas women weighing more than 70 kg had an OR of 0.91 (95% CI 0.53-1.56). Women with low recent leisure physical activity (less than 1 h/week) similarly benefited more from HRT for hip fracture prevention than women with a higher degree of recreational physical activity. The observed interactions with weight and physical activity suggest that HRT has the best protective effect against hip fracture among high-risk women.

Age Factors↗
PubMed1998

Association of family history and other risk factors with breast cancer risk (Sweden).

OBJECTIVES: Women with a family history of breast cancer have an increased risk for the disease. However, the combined impact of family history and other risk factors on breast cancer risk is unclear. We conducted a large epidemiologic study to examine this issue. METHODS. In a population-based case-control study in all of Sweden, 3,345 women aged 50 to 74 years with invasive breast cancer (84 percent of all eligible), and 3,454 controls of similar age (82 percent of all selected) were included. Mailed questionnaires and telephone interviews were used to collect detailed information on potential breast cancer risk factors. Odds ratios (OR) and 95 percent confidence intervals (CI) were estimated through multiple logistic regression. RESULTS: Women with a history of breast cancer in any first-degree relative had an increased risk of breast cancer compared with those without such a history (OR = 1.96, CI = 1.67-2.30). There was no clear indication of a differential impact of hormonal risk factors (age at menarche, parity, age at first birth, age at menopause, use of exogenous hormones, and weight gain) or body build at age seven among women with and without a positive family history. Yet, benign breast disease and height clearly were related to breast cancer risk in subjects without a family history, whereas seemingly not so in women with a family history. Formal tests for interaction between family history and these factors, however, did not prove statistically significant. CONCLUSIONS: Our findings indicate that established risk factors entail similar associations with breast cancer risk among women with and without family history of the disease.

Aged↗
PubMed1998

Recent trends in breast cancer incidence in Sweden.

Breast cancer incidence in Sweden during the period 1984-93 shows no clear trend in women aged below 40 years but a transient increase at ages 50-69 years, probably as a result of mammography screening. Our data give no indication that use of oral contraceptives or replacement hormones have affected nationwide breast cancer incidence rates.

Adult↗
PubMed1998

Hormonal aspects of epithelial ovarian cancer: review of epidemiological evidence.

Epithelial ovarian cancer is fairly common with high rates in Scandinavia, intermediate rates in western Europe and North America and low rates in the developing countries and in Japan. The 5-year survival rate is less than 40%. Increasing parity consistently gives a strong protection against epithelial ovarian cancer. A lesser degree of protection is probably derived from incomplete pregnancies and lactation. Ages at menarche and menopause are most probably weak predictors of epithelial ovarian cancer risk. Ever users of oral contraceptives (OC) have 30% lower risk compared to never users. The protection increases with duration of OC use, being about 50% after 5 years. The reduced risk among past OC users persists for at least 10 years after cessation of use. Results concerning hormone replacement therapy (HRT) and epithelial ovarian cancer risk are conflicting, but most data point to a weak or no association, but as an increasing number of women use HRT it still seems important to resolve any potential effect. Infertility adds to epithelial ovarian cancer risk in nulliparous women, while temporary fertility problems in parous women do not appear to increase risk. A possible independent risk effect of fertility drug use has not been easy to assess and remains unresolved. It has been particularly difficult to separate the effects of fertility drugs from those of infertility. Tubal ligation and hysterectomy convey protection against epithelial ovarian cancer, possibly through a suppressed ovarian hormone production. The causes of epithelial ovarian cancer are poorly understood, but reproductive hormones are thought to be involved in the aetiology. For a long time the 'incessant' and 'gonadotrophin' hypotheses have been promoted in relation to carcinogenesis. Both hypotheses find support in ovarian cancer epidemiology, and recent progress in molecular biology adds to the understanding of possible aetiological mechanisms. Another hypothesis focuses on the retrograde transport of contaminants or carcinogens through the Fallopian tubes. It is important to establish if the same risk factors apply to the various histological types of ovarian cancer, as particularly the mucinous ovarian tumours seem to present with different risk factors. Another question to resolve is if sporadic vs. inherited cases carry distinct risk profiles. As the hypotheses above do not explain all of the results derived from ovarian cancer epidemiology, there is a need to test additional hypotheses to possibly define preventive programmes and to come closer to the cause of ovarian cancer.

Adenocarcinoma↗
PubMed1998

Oral contraceptive use: interview data versus pharmacy records.

BACKGROUND: If women tend to forget and underreport their past oral contraceptive (OC) use, but the recall among cases is enhanced by the presence of disease, recall bias may explain some reported health effects of OC use. METHODS: Two different sources of information on lifetime OC use were compared for 427 (84%) of a community-based sample of 511 women aged 20-34: (i) structured interviews, using a life event calendar and picture display as memory aids, and (ii) a register of all prescriptions dispensed by pharmacies in the county since 1970. RESULTS: Interview data and pharmacy records showed high levels of agreement for any OC use, current use, time since first and last use, total duration of use, and for duration of use in different 'time windows'. But there was a tendency to under-report specific kinds of OC used in the past. CONCLUSION: Underreporting of OC use among non-cases would usually introduce little or no bias (as compared to pharmacy records) for this kind of interview and women. However, it may be preferable to use interviews for current OC use, and pharmacy records for specific kinds of OC used in the past.

Adult↗
PubMed1997

Hormone replacement therapy and the risk of breast cancer. Nested case-control study in a cohort of Swedish women attending mammography screening.

There is concern that hormone replacement therapy (HRT) increases the risk of breast cancer. We undertook a case-control study of this risk relationship within a cohort of 40- to 74-year-old women in Uppsala County, Sweden, who participated in mammography screening. Incident cases of breast cancer were ascertained during 5 years of follow-up. In all, 435 cases (87% invasive, 13% in situ cancers) were detected, 313 through screening and 122 through clinical diagnosis. As controls, 1,740 women were selected randomly. Information on risk factors and use of HRT was obtained through interviews before the start of follow-up. Multivariate analyses revealed an increased risk among users of any type of HRT for more than 10 years, the odds ratio (OR) being 2.1 (95% confidence interval [CI] 1.1-4.0), as well as when restricting analyses to cases diagnosed through mammography screening. After stratification for compound type, risk estimates were apparently higher among women reporting estradiol-progestin combined treatment vs. estradiol or conjugated estrogens alone, with ORs for more than 10 years of intake being 2.4 (95% CI 0.7-8.6) and 1.3 (95% CI 0.5-3.7), respectively. Analyses through a model including both compound type and length of hormone intake confirmed a significant excess risk linked to treatment for more than 10 years, OR = 2.6 (95% CI 1.3-5.1). Our results indicate a moderately increased risk of breast cancer after many years of HRT and, hypothetically, a further enhancement of the risk with added progestins.

Adult↗