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ORIGINAL RESEARCH |
From the Department of Family Medicine, College of Medicine, and Departments of Biostatistics and Epidemiology, College of Public Health, University of Iowa, Iowa City, Iowa.
Address reprint requests to: Barcey T. Levy, PhD, MD, University of Iowa, Department of Family Medicine, 01292 East Pomerantz Family Pavilion, Iowa City, IA 52242; E-mail: barcey-levy{at}uiowa.edu.
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ABSTRACT |
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 ABSTRACT MATERIALS AND METHODSRESULTSDISCUSSIONREFERENCES |
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METHODS: We conducted a cross-sectional study of 426 postmenopausal women seen for their annual examination at university clinics. Logistic regression was used to identify predictors of current versus never HRT use.
RESULTS: Overall, 60% of women recruited in family practice clinics and 69% in gynecology clinics were current HRT users. Significant, positive, multivariable predictors of HRT use were gynecology versus family practice clinic attendance (odds ratio [OR] 2.6, 95% confidence interval [CI] 1.4, 4.6), surgical menopause (OR 2.3, 95% CI 1.2, 4.6), history of depression (OR 2.3, 95% CI 1.2, 4.7), at least two live births (OR 2.1, 95% CI 1.1, 4.0), and current alcohol use (OR 1.8, 95% CI 1.04, 3.2). Significant, negative, multivariable predictors were increasing age (60–70 years versus less than 60 years, OR 0.4, 95% CI 0.2, 0.8; 70 years or older versus less than 60 years, OR 0.4, 95% CI 0.2, 0.9) and history of breast cancer (OR 0.04, 95% CI 0.01, 0.14). Sociodemographic factors, smoking status, number of self-reported medical conditions, number of prescription medications besides HRT, oral contraceptive use, history of hypertension, and exercise level were tested as covariates and did not enter the model.
CONCLUSION: Although current HRT use rates between clinics were similar and higher than national averages, we found that the adjusted odds of current HRT use among women receiving care from gynecologists was 2.6 times that among women receiving care from family physicians. This practice variation may reflect physicians’ uncertainty surrounding the preventive value of HRT.
Physicians have been advised to consider estrogen for their postmenopausal patients.1,2 Hormone replacement therapy (HRT) reduces the risk of heart disease3–5 and osteoporotic fractures5,6 in postmenopausal women. Some studies also have found that HRTs are associated with a reduced risk of Alzheimer’s disease7–9 and colon cancer.10–12 These benefits must be tempered with the possibly elevated risk of breast cancer for women on HRT,5,13–16 although these tumors have been shown to be more differentiated and less aggressive.17,18
Despite the fact that use of HRT has been encouraged, current use of HRT in the United States is estimated at only 38% among postmenopausal women.19 Many women who start HRT do not continue this treatment.20 Benefits of HRT for heart disease and osteoporosis are likely to require long-term treatment. Although the rate of HRT use has been increasing in the United States,21 if benefits outweigh the risks, there are still large numbers of women who could potentially benefit from HRT.22,23
Several studies have reported that gynecologists feel more strongly than other physicians about the preventive role of HRT.24–27 However, we could find no studies comparing current HRT use in women seen by gynecologists versus family physicians for their annual examinations while controlling for sociodemographics, preventive health behaviors, and comorbidities of the patients. The purposes of this paper were to: 1) compare the characteristics of postmenopausal women seen by gynecologists versus family physicians, and 2) determine factors associated with current HRT use.
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MATERIALS AND METHODS |
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Women presenting for their annual examination were recruited by trained research assistants using appropriate informed consent procedures approved by the University of Iowa Institutional Review Board. The refusal rate was 5%. During the study period, the 426 women reflect the number of women we were able to recruit into the study using appropriate informed consent procedures. Because of other constraints on the research assistants’ time and the fact that informed consent was necessary, not all postmenopausal women presenting for annual examinations could be approached. Sample size calculations were not considered because there were no prior studies on which to base sample size. The research assistant verbally asked each participant a series of questions regarding current and past history of HRT use and current medications. Women were classified as current, past, or never HRT users. Women completed a 6-page risk factor questionnaire designed to collect information on demographics, health behaviors, medical history, and sexual history.
From the patient questionnaire data, analytic variables were created for exercise level, number of prescription medications, and number of medical conditions. Exercise level was determined by the following formula: 1 (number of days of the week exercise lightly for at least 30 minutes) +2 (number of days of the week exercise moderately for at least 30 minutes) +3 (number of days of the week exercise vigorously for at least 30 minutes). Number of medical conditions was determined from the following conditions inquired about pertaining to medical history: migraine headaches, gallbladder disease, diabetes, hypertension, depression, peptic ulcer disease or reflux esophagitis, hypothyroidism, hyperthyroidism, spinal or hip fracture, heart attack, blood clot, stroke, congestive heart failure, breast cancer, colon cancer, asthma, rheumatoid arthritis, liver disease, or other serious or major disease. Prescription medications included 74 coded types from among the following general headers: psychiatric drugs, other neurologic drugs, anticoagulants, cardiovascular drugs, thyroid agents, gastrointestinal drugs, anti-inflammatory drugs, analgesics, respiratory drugs, allergy shots, diabetes, anorexiant agents, antineoplastic agents, urologic disorder drugs, supplemental vitamins and minerals, vaginal preparations, osteoporosis drugs, other hormones, antibiotics, and musculoskeletal agents.
The Pearson 
2 or Fisher exact test was used to compare categoric variables, and the Wilcoxon rank sum test was used to compare continuous variables between the two clinics. For some of the questions, especially those pertaining to reasons for HRT use, the possible responses were yes, no, and unsure. We analyzed the data two ways: 1) by including the unsure cases as a separate category, and 2) by excluding the unsure cases. Results were very similar because of the low number of unsure responses. Percentages and P values reported in the tables are based on exclusion of the unsure cases.
Backward stepwise logistic regression models with significance set to P < .05 were used to determine factors predicting current versus never HRT use. Past users were not included in the analyses because they likely represent a different group of women than never users. We chose the never HRT users as the referent group. Covariates considered in the modeling process included: sociodemographics (age group less than 60 years, 60–69 years, 70 years or older), race (white versus nonwhite), marital status (married versus other), educational level (some college or higher versus high school or less), family income (less than $35,000, $35,000 to $74,999, $75,000 or higher), exercise level, smoking status (ever versus never), alcohol use (current versus past/never), clinic attended (gynecology or family practice), history of specific medical conditions (hypertension, depression, breast cancer), number of prescription medications excluding estrogen and progestin, past oral contraceptive use, surgical menopause (hysterectomy or bilateral oophorectomy versus natural menopause), number of medical conditions, and parity (two or more versus zero to one births). Because women attending the menopause clinic (an area within the gynecology clinic) might differ from other women attending the gynecology clinic with regard to HRT use, we considered those women separately in some of the regression analyses. The menopause clinic is staffed by a generalist obstetrician-gynecologist and a nurse practitioner. Ninety-five percent confidence intervals (CI) for crude and adjusted odds ratios (OR) for current HRT use were calculated using the standard errors from the logistic regression models and the normal approximation. All reported P values were two sided. All analyses were performed using the SAS statistical package 8.0 (SAS Institute, Cary, NC).
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RESULTS |
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compares the characteristics of women seen in the family practice versus gynecology clinics. Demographics were generally similar, but family income was lower among women seen by family physicians. Overall, 60% of women recruited in family practice clinics and 69% in gynecology clinics were current HRT users. Women seen in family practice clinics were less likely to smoke and more likely to have hypertension. Reproductive factors were quite similar between clinics, with the exception that patients from family practice clinics had significantly shorter length of menses, later age at first intercourse, and higher rates of past condom use. Hysterectomy rates were not statistically different between the two clinics. Only one woman had a bilateral oophorectomy.
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). The most common reason for currently using HRT was menopausal symptoms, with women seen by gynecologists more likely to cite this than women seen by family physicians. Other common reasons for currently taking HRT included prevention of osteoporosis and heart disease, with no significant differences between the two groups of patients. Reasons for not currently taking HRT did not differ significantly between the clinics, with the exception that concern about side effects was cited more often among women seen by family physicians. Close to one-third of the women not currently on HRT were worried about the risk of cancer, reported their menopausal symptoms were tolerable, or did not like taking medication.
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). Many women reported weight gain, with no significant difference by clinic. Reasons for discontinued use did not differ significantly by clinic with approximately 5% of women overall reporting fear of breast cancer. Despite a significant percentage of women reporting weight gain, only 4% reported that this was a factor that led to discontinuation.
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examines the bivariate associations between current HRT use and characteristics of women in the study. Characteristics significantly associated with current HRT use were: younger age, higher income, higher educational level, past oral contraceptive use, self-reported history of depression, no history of breast cancer, attending the gynecology clinic, and having had a surgical menopause. Factors not significantly associated with current HRT use were: race, employment status, marital status, exercise level, body mass index, number of self-reported medical conditions, number of medications, number of live births, and self-reported history of hypertension. Current alcohol use approached significance.
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). Significant, positive, independent predictors included: attending the gynecology versus the family practice clinic, surgical menopause, history of depression, current alcohol use, and greater number of live births. Significant, negative, independent predictors included older age groups and history of breast cancer. Attendance in the menopause clinic (part of the gynecology clinic) versus family practice clinic was not significantly associated with HRT use (adjusted OR 1.2, 95% CI 0.6, 2.7). Race, educational level, marital status, income, smoking status, history of hypertension, number of prescription medications excluding estrogen and progesterone, number of medical conditions, and past oral contraceptive use did not enter the final model. When the regression was run at the P < .1 level, the only other variable to enter was race, with white women being more likely to be HRT users (OR 3.1, 90% CI 1.1, 8.6). The inclusion of race did not change the adjusted ORs for the other variables in the model.
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DISCUSSION |
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Excluding past users, the rate of current HRT use among women seen by gynecologists was 80% compared with 66% among women seen by family physicians. These rates translated to an adjusted OR of 2.6. All other factors being equal, why was the odds of current HRT use over 2 among women receiving annual examination care from a gynecologist as compared with a family physician? Perhaps gynecologists see more women likely to accept HRT, they are better at maintaining compliance with HRT, or they feel more strongly about the value of HRT compared with family physicians. Recent reports28–30 suggest that the latter might be the case. These reports strongly encourage the use of postmenopausal HRT, stating that "estrogen and hormone replacement therapy improves the quality of life and increases life expectancy for most menopausal women"28 and "the benefits of hormone replacement therapy outweigh any associated risks."29 Connelly et al found that provider opinion was critical to women’s decision making with regard to HRT.30
Several studies have found that gynecologists reported being more likely to prescribe HRT than other physicians,24,25,27 whereas another study did not confirm this.31 However, these studies did not report actual prescription rates, only physicians’ responses about whether they would prescribe HRT given hypothetic clinical scenarios. Obstetrician-gynecologists were more likely than family physicians and internists to report they believed in the preventive value of HRT.26,27 We found no difference between clinic settings in percentages of current HRT users who reported using HRT for osteoporosis or heart disease prevention, with close to half of all women reporting current HRT use for these reasons. Stafford et al,23 using National Ambulatory Medical Survey data and multivariable logistic regression, found that gynecologists were four times as likely as family physicians or internists to prescribe HRT for women without menopausal symptoms, but that in women with menopausal symptoms, these differences were not apparent.
If family physicians in our sample were dealing with more health problems during their patients’ annual examinations, then the HRT issue might be underad-dressed. Redelmeier et al32 found that patients 65 and older with diabetes mellitus were significantly less likely to receive estrogen than other patients (OR 0.4, 95% CI 0.37, 0.43). Our analyses showed no relationship between HRT use and hypertension, number of medical conditions, or number of medications besides HRT a patient was using. Not surprisingly, women with a history of breast cancer were significantly less likely to be on HRT.
Perhaps we should not be surprised about the differences in current HRT use between the women attending the two clinics. Small area practice variation has been found in a number of clinical areas, especially when there is uncertainty about the value of a treatment.33 Yankowitz et al found that obstetricians were significantly more likely than family physicians to order prenatal triple screening.34 Roos concluded that hysterectomy rate differences were "due as much to the practice style of physicians as to gynecologic need."35 Other studies have found striking differences in patterns of HRT use depending on where one lives in the United States, with women from the West and South being significantly more likely to be using HRT than their counterparts in the Northeast.19,23 In addition, there are wide variations in developed countries around the world, with the highest rates in the United States, lower rates in the United Kingdom and Scandinavian countries, and lowest rates in continental Europe.36 The overall percentage of current HRT users in our population (67%) was higher than that reported in recent studies, where prevalence of current HRT ranges from 37% to 43%.19,20 Thus, the physicians in this study appear to be supportive of the idea that HRT may be beneficial for the majority of women.22,28,29
The decision to initiate postmenopausal HRT for prophylaxis is complex. New evidence regarding risks and benefits accumulates rapidly, with a recent expert panel concluding there is little or no benefit of HRT for the treatment of conditions other than menopause.37 The clinician attempting to counsel a woman regarding HRT must sift through information from various types of studies, many of which have yielded inconsistent results. Although some specialty physician groups have formulated practice guidelines regarding HRT for prophylaxis, including the American College of Physicians,2 the U.S. Preventive Health Services Task Force,1 and The North American Menopause Society,38 these guidelines are not always helpful. For example, although the U.S. Preventive Health Services Task Force concluded that all postmenopausal women should be counseled about the potential risks and benefits of hormone prophylaxis, they also stated that there is insufficient evidence to recommend for or against it.1 Given the uncertainty in the value of HRT, physicians are left to decide their own prescribing philosophy. Perceived uncertainty in treatments has been shown to lead to practice variation.33
Clinicians have been advised to consider many aspects in this decision, including recent scientific evidence and women’s thoughts, concerns, and individual risk factors.39 Many physicians report that they have insufficient knowledge and lack of time to counsel their patients.26,40 Although there are abundant data from observational studies that long-term HRT is associated with reduced risk of cardiovascular disease3,41 and osteoporosis6,42 compared with no treatment, these studies have been criticized because they are observational and may not have taken into account unrecognized confounders. Women taking HRT in these studies are generally healthier than those not taking HRT,43 and the results of the observational studies may overestimate the purported benefits of HRT, even though investigators have tried to control for confounders. The results of the Women’s Health Initiative, a randomized, primary prevention trial of 27,500 women assigned to HRT versus placebo will not be available until about 2005.44 In 2000, investigators informed participants in the Women’s Health Initiative that during the study’s first 24 months, there were small increases in the number of myocardial infarctions, strokes, and thromboembolisms in women taking HRT or ERT compared with those taking placebo.45 The results of two randomized trials have called into question the established practice of recommending HRT for women with preexisting heart disease,46,47and the American Heart Association now recommends that HRT not be initiated for secondary prevention of cardiovascular disease in postmenopausal women.48 The North American Menopause Society recently published algorithms for HRT that include the statement, "For postmenopausal women who have established coronary heart disease, use other appropriate treatments rather than initiate continuous-combined conjugated equine estrogens and medroxyprogesterone acetate."38
We found a strong age-cohort effect. Compared with women less than 60 years old, women aged 60–69 years (OR 0.4) and women 70 years and older (OR 0.4) were more than half as likely to be current HRT users. Keating et al also found similar trends among women in their nationally representative sample, but their results did not reach statistical significance,19 and Whitlock et al reported the highest HRT prescription rates for women 50–59 years of age.49 In our study, hysterectomy (OR 2.3) and current alcohol use (OR 1.8) were strong predictors of HRT use as has been shown in other studies.19,21
An interesting finding that deserves further study is that women who reported a history of depression were 2.3 times as likely to be current HRT users as those women without this history. Perhaps these women were having more severe menopausal symptoms or were more willing to use HRT. Or perhaps they had increased contact with their health care provider and thus a greater number of opportunities for HRT counseling and prescription. Keating et al found that self-report of anxiety or depression was associated with HRT use in bivariate, but not multivariable analyses.19 Similar to the findings of others, hypertension was not predictive of HRT use.19,21,23
Reasons women cited for not taking HRT were consistent with other studies,20 and included tolerable menopausal symptoms, concern about side effects, and concern about risk of cancer. Researchers have found that women fear breast cancer more than cardiovascular disease, even though cardiovascular disease causes more morbidity and mortality.50
Our study is one of the few to obtain information about HRT use directly from women, while controlling for a large number of factors, which could affect HRT use. Limitations to this study include the fact that it was a relatively small study of predominantly white, well-educated women recruited from patient care centers associated with a single university medical center, and results may not be representative of the population as a whole. However, these women are most likely representative of the population of postmenopausal women willing to use HRT and continue regular gynecologic care. We did not ask every woman about menopausal symptoms, and thus could not control for this in the model. Patients self-reported their medical conditions. Because the university where these patients were studied participated in the Postmenopausal Estrogen/Progestin Interventions trial51 and the Women’s Health Initiative,44 the physicians whose patients were studied may be more accepting of HRT and more aware of its potential benefits than physicians elsewhere.
Although overall HRT use was high, specialty of the treating physician was a significant predictor of women’s HRT use, even after controlling for other factors, which might affect HRT use. Part of this practice variation may be explained by differences in the perception of the value of HRT between gynecologists and family physicians, given the confusing plethora of evidence regarding the effectiveness of HRT. Future studies of HRT use should explore how physicians evaluate the existing evidence for individual patients.
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Footnotes |
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Received October 25, 2001. Received in revised form June 12, 2002. Accepted July 18, 2002.
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REFERENCES |
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2. Guidelines for counseling postmenopausal women about preventive hormone therapy. American College of Physicians. Ann Intern Med 1992;117:1038–41.
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6. Maxim P, Ettinger B, Spitalny GM. Fracture protection provided by long-term estrogen treatment. Osteoporos Int 1995;5:23–9.[Medline]
7. Waring SC, Rocca WA, Petersen RC, O’Brien PC, Tangalos EG, Kokmen E. Postmenopausal estrogen replacement therapy and risk of AD: A population-based study. Neurology 1999;52:965–70.
8. Baldereschi M, Di Carlo A, Lepore V, Bracco L, Maggi S, Grigoletto F, et al. Estrogen-replacement therapy and Alzheimer’s disease in the Italian Longitudinal Study on Aging. Neurology 1998;50:996–1002.
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13. Breast cancer and hormone replacement therapy: Collaborative reanalysis of data from 51 epidemiological studies of 52,705 women with breast cancer and 108,411 women without breast cancer. Collaborative Group on Hormonal Factors in Breast Cancer. Lancet 1997;350:1047–59.[Medline]
14. Persson I, Weiderpass E, Bergkvist L, Bergstrom R, Schairer C. Risks of breast and endometrial cancer after estrogen and estrogen-progestin replacement. Cancer Causes Control 1999;10:253–60.[Medline]
15. Schairer C, Lubin J, Troisi R, Sturgeon S, Brinton L, Hoover R. Menopausal estrogen and estrogen-progestin replacement therapy and breast cancer risk. JAMA 2000; 283:485–91.
16. Magnusson C, Baron JA, Correia N, Bergstrom R, Adami HO, Persson I. Breast-cancer risk following long-term oestrogen- and oestrogen-progestin-replacement therapy. Int J Cancer 1999;81:339–44.[Medline]
17. Gapstur SM, Morrow M, Sellers TA. Hormone replacement therapy and risk of breast cancer with a favorable histology: Results of the Iowa Women’s Health Study. JAMA 1999;281:2091–7.
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19. Keating NL, Cleary PD, Rossi AS, Zaslavsky AM, Ayanian JZ. Use of hormone replacement therapy by post-menopausal women in the United States. Ann Intern Med 1999;130:545–53.
20. Newton KM, LaCroix AZ, Leveille SG, Rutter C, Keenan NL, Anderson LA. Women’s beliefs and decisions about hormone replacement therapy. J Women’s Health 1997;6: 459–65.[Medline]
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