Hormone Replacement Therapy: A Survey of Irish General Practitioners. U FALLON, C KELLEHER. Department of Health Promotion, Clinical Science Institute,.
Hormone Replacement Therapy: A Survey of Irish General Practitioners U FALLON, C KELLEHER Department of Health Promotion, Clinical Science Institute, National University of Ireland, Galway. Abstract We report findings of a cross-sectional postal survey of current prescribing practices of hormone replacement therapy (HRT) by Irish General Practitioners from a random sample of 600 Irish College of General Practitioners members. Median estimated prescribing rate of HRT was 17.5% (interquartile range 10 to 30%). The majority of General Practitioners would prescribe for the prevention of osteoporosis but there was some reluctance to prescribe solely for the prevention of CVD. Common cardiovascular conditions were regarded as contraindications to HRT by nearly one-third of GPs. Female GPs were more likely than males to request mammography (p< 0.002), to consider a first degree relative with breast cancer a contraindication (p< 0.01) and less likely to prescribe HRT for longer than 10 years (p 5 years after 124 (37.6) 166 (50.3) 120 (36.4 menopause* ) > 10 years after 69 (20.9) 93 (28.2) 62 (18.8 menopause* ) before periods stop* 268 (81.2) 117 (35.5) 86 (26.1 ) at oopherectomy* 255 (77.3) 251 (76.1) 198 (60.0 )
*not exclusive categories
Table 2 illustrates that the presence of symptoms and risk factors strongly influenced their willingness to prescribe, particularly in the case of CVD prevention where 81 (24.5%) would prescribe only if the woman was at high risk and 19 (5.8%) omitted to answer this question. Table 2 also shows how many years after menopause General Practitioners would consider starting HRT for different indications. Osteoporosis was the single largest indication for starting HRT after menopause in the time categories shown. General Practitioners were also asked for what indications they prescribe HRT in order of frequency. Two hundred and fifty-nine (78.5%) respondents gave relief of menopausal symptoms s the most common reason. Prevention of osteoporosis was the next most frequently given indication, followed by early menopause. Prevention of CVD was cited by 170 General Practitioners (51.5%) as their least frequent indication for prescribing. Fifty-five (16.7%) respondents did not rank the prevention of CVD at all as a possible indication. Figure 1 shows that General Practitioners are clearly willing to prescribe for longer periods for all indications in women who have a history of oopherectomy. General Practitioners were asked whether the possibility that HRT increases the risk of breast cancer, discouraged them from prescribing it for longer than 10 years (table 3). In general, respondents were evenly divided on this question if the woman was at high risk of osteoporosis or CVD. However, the majority of General Practitioners agreed they would be discouraged for this reason if the woman was not at risk of CVD or osteoporosis; female General Practitioners being more likely to say so than men (p < 0.0001). This difference remained highly significant when controlled for age, type of practice, position within the practice and being vocationally trained where the adjusted odds ratio of being female and answering yes to this question was 3.7 (95% Cl 2.04 - 6.8) (p < 0.0001). Female General Practitioners were also more likely to send their patients for mammography before prescribing HRT (adjusted OR 2.3) (95% CI 1.4-4.1) (p=0.003) and at regular intervals while on HRT (adjusted OR 2.6) (95% CI 1.44.8)
Table 3 Prescription practice of general practitioners in relation to risk of breast cancer GPs discouraged from prescribing HRT for > 10 years because of risk of breast cancer Case Scenario
yes
no
n
(%)
n
not answered (%)
total
n
(%)
n
(%)
patient at high risk of CVD Total
147
(44.5)
172
(52.1)
11
(3.3)
330
(100)
Male
85
(40.3)
117
(55.5)
9
(4.3)
211
(100)
Femal
62
(52.1)
55
(46.2)
2
(1.7)
119
(100)
Patient at high risk of CVD Total
169
(52.2)
148
(44.8)
13
(3.9)
330
(100)
Male
100
(47.4)
103
(48.8)
8
(3.8)
211
(100)
Femal
100
(84)
16
(13.4)
3
(2.5)
119
(100)
Patient not at high risk of either Total
222
(67.3)
89
(27)
19
(5.8)
330
(100)
Male
122
(57.8)
73
(34.6)
16
(7.6)
211
(100)
Femal
100
(84)
16
(13.4)
3
(2.5)
119
(100)
GP who routinely send their patients for mammography when prescribing HTR Yes n
No (%)
n
Not answered (%)
Total n
(%)
Before prescribing HRT Total
192
(58.2)
125
(37.8)
13
(3.9)
330
(100)
Male
109
(51.6)
96
(45.5)
6
(2.8)
211
(100)
Femal
83
(69.7)
29
(24.4)
7
(5.9)
119
(100)
At regular intervals while on HRT Total
192
(58.2)
125
(37.8)
13
(3.9)
330
(100)
Male
109
(51.6)
96
(45.5)
6
(2.8)
211
(100)
Femal e
83
(69.7)
29
(24.4)
7
(5.9)
119
(100)
(p = 0.002). Females were more likely to say that breast cancer in a first degree relative was a contraindication or a relative contraindication to HRT. Again this remained significant when adjusted for all other factors (OR 2.3) (95% CI 1.2 - 4.4) ( p = 0.011).
Table 4 shows how General Practitioners regarded some common cardiovascular conditions in terms of contraindications and relative contraindications. Two hundred and forty-three (73.6%) General Practitioners agreed that HRT should be offered to all women age 50 to 65 years assuming no contraindications. General Practitioners were asked about entering their female patients into a randomised controlled trial of HRT. Thirty-three (10%) said “yes definitely”, 126 (39%) said “yes probably”, 95 (28.8%) said “no probably” and 70 (21.2%) said “no definitely”. The only feature associated with being interested in participating was being a practice principal (adjusted OR 2.6) (95% CI 1.2 -5.7) (p=0.022). Table 4 Arteriosclerotic conditions likely to act as contraindications to prescribing HRT: Contraindicated
no
yes
relative
no answer
total
n
(%)
n
(%)
n
(%)
n
(%)
n
(%)
ischaemic heart disease
29
(8.8)
227
(68.8 )
66
(20.0 )
8
(2.4)
330
(100 )
Cerebrovascula r disease
47
(14.2 )
167
(50.6 )
99
(30.0 )
17
(5.2)
330
(100 )
Angina
31
(9.4)
216
71
(3.4)
330
18
(5.5)
195
(21.5 ) (31.2 )
12
hypertension
(65.5 ) (59.1 )
14
(4.2)
330
(100 ) (100 )
103
Discussion The estimated median prescribing rate of HRT is consistent with estimates from other developed countries. This figure remains to be validated by a notesearch in a sample of practices. However, population studies of women’s health in Ireland, indicate that this is more likely to be the proportion of women who have ever taken HRT rather than the proportion currently taking it91”. The range of estimated prescribing rate is quite wide, indicated by a large interquartile range. One of the striking features of this survey is that GPs appear to be confident about prescribing for menopausal symptoms in the short term and for the prevention of osteoporosis in the long term but they expressed considerable uncertainty about prescribing for the prevention of CVD over long periods of time even though CVD is the commonest cause of death and disability in postmenopausal Irish women”. Of those who do prescribe for this reason, there is a tendency to do so only if risk factors are present or if the patient is at high risk of CVD. Most of these will prescribe for up to 10 years and again more will prescribe for longer durations if the woman has a history of oopherectomy. A number of common cardiovascular conditions were indicated by some General Practitioners as relative or absolute contraindications. For instance up to one third of General Practitioners stated that hypertension was a relative contraindication. In fact both the PEPI trial13 and the Medical Research Council study of women who have had a hysterectomy11 have shown that HRT does not have any significant effect on blood pressure and some smaller studies indicate it might even be beneficial14. Since hypertension is a major risk factor for coronary heart disease then HRT might arguably be positively indicated. Similarly, angina and ischaemic heart disease were frequently indicated as relative or absolute contraindications. Given the volume of epidemiological literature about the cardio-protective effect of HRT, prescribing policy with regard to the prevention of CVD appears relatively conservative. However, such evidence does not come from randomised controlled trials so scepticism is understandable and emphasises the urgent need for such trials”. Overall, there were no significant variations in prescribing patterns with age, as might be expected, but there were some differences with gender. Female General Practitioners were more likely to have reservations about the risk of breast cancer, reflected in their caution about prescription in the case of a significant family history and their greater likelihood of routinely sending their patients for mammography screening both before prescribing HRT and at regular intervals while on HRT. Despite this, female General Practitioners estimated
that they prescribe more HRT than male General Practitioners. One possible explanation is that female GPs may see more women patients in this age category than their male counterparts. Unfortunately there is no information available on age/gender ratios of attendance at male and female GPs. There are other possible explanations for the differences. Concern about unnecessary medicalisation of the menopause is a controversial issue for women generally16. Increased sensitivity to breast cancer by GPs as women themselves may also be a factor. It is beyond the scope of this study to speculate on these reasons, but such differences indicate the need for further research on this issue. Interestingly, a recent survey of female menopausal GPs in the United Kingdom found nearly half had tried HRT and 41.2% were current users, the highest rate in any professional group17,18. Correspondence: C Kelleher, Department of Health Promotion, Clinical Science Institute, National University of Ireland, Galway. Acknowledgements We thank Helen Wilkes of the Medical Research Council Epidemiology and Medical Care Unit for affording access to her original questionnaire and for advice and comments on study design and analysis. We also wish to thank the Irish College of General Practitioners for access to their database. References 1. 2. 3.
4. 5. 6. 7.
8. 9. 10. 11. 12.
13.
14. 15. 16.
17. 18.
Smith DC. Prentice R, Donovan JT, et al. Association of exogenous oestrogen and endometrial carcinoma. N Engl J Med 1975; 293: 1164-7. Colditz GA, Hamkinson SE, Hunter DJ et al. The use of estrogens and progestins and the risk of breast cancer in postmenopausal women. N Engl J Med 1995; 332: 1589-93. Collaborative Group on Hormonal Factors in Breast Cancer. Breast cancer and HRT: collaborative reanalysis of data from 51 epidemiological studies of 52,705 women with breast cancer and 108,411 women without breast cancer. Lancet 1997; 350:1047-59 Stampfer MJ, Colditz GA. Oestrogen replacement therapy and coronary heart disease: a quantitative assessment of the epidemiological evidence. Preventive Medicine 1991; 20: 47-63. Grady D, Rubin SM, Pettiti DB et al. Hormone Therapy To Prevent Disease and Prolong Life in Postmenopausal Women. Ann Int Med 1992; 117: 1016-37. Matthews KA, Kuller LH, Wing RR, Meilahan EN, Plantinga P. Prior to use of Estrogen Replacement Therapy, Are Users healthier than Nonusers? Am J Epidemiol 1996; 143: 971-8. Fallon UB, Kelleher CC, Shannon W, McDonnell MM. Randomised controlled trial of HRT in Irish general practice; a feasibility study. J. Irish College of Physicians and Surgeons 1999; 28: 86^90. Wilkes HC, Meade TW. HRT in general practice; a survey of doctors in the Medical Research Council’s general practice research framework. BMJ 1991; 302: 1317-20. Wiley MM, Merriman B. Women and health care in Ireland; knowledge, attitudes and behaviour. Dublin: The Economic and Social Research Institute, 1996. Happy Heart National Survey ; a report on Health Behaviour in Ireland. Irish Heart Foundation April 1994. Shaping a Healthier Future. Dublin: Department of Health, 1994 The Writing Group for the PEPI Trial. Effects of estrogen and progestins and the risk of breast cancer in postmenopausal women. The Postmenopausal Estrogen/Progestin Interventions (PEPI) trial. JAMA 1995; 273: 188-208. Medical Research Council’s General Practice Research Framework. Randomised comparison of oestrogen versus oestrogen plus progestogen HRT in women with hysterectomy. BMJ 1996; 312: 473-478. Lip G, Beevers M, Churchill D, Beevers DG. Do Clinicians prescribe HRT for hypertensive postmenopausal women? B J Clin Pract 1995; 49: 61-64. Hannaford PC. Editorial: Is there sufficient evidence for us to encourage the widespread use of HRT to prevent disease? Br. J. Gen. Pract. 1998; 48: 951-952. Kelleher CC . HRT: is it good for women’s health? pp: 153 - 158. In: Byrne A, Conroy J and Ryder S (Eds.) UCG Women’s Studies Centre Review, Vol. 2. University College Galway: Women’s Studies Centre, 1993. Isaacs AJ, Britton AR, McPherson K. Utilisation of HRT by women doctors. BMJ 1995; 311: 1399-401. Norman GS, Studd JWW. A survey of views on HRT. Brit J Obs Gynae 1994; 101: 879-887.
