Differences in hormone replacement therapy use by social class,region and psychological symptoms

Sunil Shaha,*, Tess J. Harrisb, Derek G. Cooka

Objective To describe the relationship between socio-demographic factors, heart disease risk factors, psycho-logical symptoms and the use of hormone replacement therapy by English women.

Design Cross-sectional analysis of a population-based survey.

Setting England.

Population 13,214 women aged 40±69 years who participated in the nurse-administered schedule of the HealthSurvey for England between 1993 and 1996.

Outcome Current hormone replacement therapy use.

Results Women from social classes II and I and women who live in the south of England were more likely to usehormone replacement therapy independently of a range of socio-demographic factors including education. Theadjusted odds ratio for social classes II and I compared with social classes IV and V was 1.51 (95% CI 1.20 to1.91) and for women in the South of England was 1.38 (95% CI 1.18 to 1.62). Women with a history of heartdisease and those with high cholesterol levels were less likely to use hormone replacement therapy. Womenwith psychological symptoms were more likely to be prescribed hormone replacement therapy, as were thosewho had recently seen a doctor.

Conclusion There is marked socio-demographic inequity in use of hormone replacement therapy. This mayaccentuate existing inequalities in health and reduce any potential bene®ts of Hormone Replacement Therapyfor public health. The relationship between psychological symptoms, use of medical services and use ofhormone replacement therapy suggests that hormone replacement therapy is prescribed for the managementof psychological symptoms.

INTRODUCTION

The use of hormone replacement therapy (HRT) isadvocated both for the relief of menopausal symptomsand prevention of chronic disease. There is still uncer-tainty on the risks and bene®ts of HRT, particularly withregards to the prevention of ischaemic heart disease andthe increased risk of breast cancer1,2. There is, however,evidence that prescription of HRT is in¯uenced by socialcircumstances and is not solely based on an objectiveassessment of risks and bene®ts. Studies in the UnitedStates and Europe have found that women with highersocial and educational status are more likely to receiveHRT, while women at high risk of osteoporosis and heartdisease are less likely to receive HRT3±7.

There is limited information on the pattern of use ofHRT in the United Kingdom with con¯icting ®ndingswith regard to the role of social circumstances8±13. A

follow up of the contraceptive study8 conducted by theRoyal College of General Practitioners failed to ®nd arelationship between social class and use of hormonereplacement therapy. However, analysis of the VAMPgeneral practice database found an effect for socialclass but not education9. Most of these studies are limitedeither by sample size or representativeness. In this paper,we use the Health Survey for England to describeinequalities in use of HRT and compare risk factors forischaemic heart disease and self-reported psychologicalstatus between users and non-users in a national sampleof women.

METHODS

Our study used data from the Health Survey forEngland for the four years, 1993 to 1996. The HealthSurvey for England is an annual survey of people livingin households in England commissioned by The Depart-ment of Health14±17. The survey is conducted in twostages with an initial administered questionnairefollowed by a nurse visit for physical measurementsand biological sampling. The survey aims to include arepresentative sample of the population and asks a vari-able range of questions on social circumstances, healthand health service use. Each survey asks standard ques-tions on socio-economic status and prescribed medica-

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PII: S0306-5456(00)00076-0

British Journal of Obstetrics and GynaecologyMarch 2001, Vol. 108, pp. 269±275

www.bjog-elsevier.com

* Correspondence: Dr S. Shah, Department of Public Health Sciences, St

George's Hospital Medical School, Cranmer Terrace, London SW17 0RE,

UK.

aDepartment of Public Health Sciences, St George's

Hospital Medical School, London, UKbDepartment of General Practice and Primary Care, St

George's Hospital Medical School, London, UK

tion. The 1993 and 1994 surveys included detailed ques-tions on heart disease and measurement of serum choles-terol. In 1993, 1994, and 1995 the General HealthQuestionnaire, a measure of psychological morbiditywas included. For 1993 and 1994 women were askedwhether their periods stopped as a result of an operation.This question was used as a proxy for hysterectomystatus. Social class, in this analysis, was de®ned on thebasis of the woman's occupation.

A total of 15,256 women aged 40-69 took part in thesurvey. This was an estimated response rate of 76% overthe four years. Medication history was available for13,214 women (87%) who cooperated with the nursevisit. Women were classi®ed as users of HRT if theirprescribed medication included non-contraceptiveoestrogens. For the years 1995 and 1996 women takingprogestogens alone could not be excluded from thisgroup. In 1993 and 1994 there were only 23 such women.

Use was analysed as a dichotomous outcome variable.Odds ratios are presented adjusted for age alone andafter adjustment for a range of socio-demographic vari-ables and history of surgical menopause. Odds ratioswere calculated using logistic regression models devel-oped in SPSS for Windows 7.5 (SPSS Inc, ChicagoIllinois, USA). The model used for socio-demographicfactors adjusted for all factors simultaneously. The logicof such an approach is that where such adjustments havelittle effect on other factors of interest, such as region,ischaemic heart disease and psychological symptoms,the evidence that the effects of interest are not due toconfounding by socio-demographic factors is strength-ened. It should be noted that as not all variables weremeasured in every year of the survey, some of theanalyses were restricted to a subset of years. This isindicated in the tables. Analyses which adjusted forhysterectomy status was only possible for 1993 and1994. As the surveys attempted to draw a representativesample in each year, this would not introduce bias intothe study.

RESULTS

One thousand nine hundred and forty-one women(14.6%) aged 40 to 69 were users of HRT. Use washighest among 50-54 year olds (28.9%) and lowestamong women over the age of 65 (4%). Use increasedannually from 12.6% in 1993 to 16.2% in 1996 (OR foryear � 1.10 (95% CI: 1.05-1.14)). Use was commoneramong women who reported that their periods stopped asa result of an operation (Table 1).

Women from social classes I and II were more likely touse hormone replacement therapy as were women wholive in households with a car, owner occupiers and thosenot in receipt of income support. Employment status wasless strongly associated with use of HRT (Table 1).

Single and widowed women and women who reportedtheir ethnic group as either black or from the Indian sub-continent were less likely to use hormone replacementtherapy. Educational status, measured by school leavingage, was not signi®cantly associated with the use of HRT.Region of residence was an important predictor of use.Women in the South of England (London, the Southeastand Southwest) were more likely to use hormone repla-cement therapy than women in the rest of England.Women in rural areas were also more likely to usehormone replacement therapy.

After adjustment for all socio-demographic factors,social class, marital status, region and ethnicity remainedimportant predictors of use of HRT (Table 1). There wasno evidence of an interaction between social class andregion.

For the 1993 and 1994 surveys, history of surgicalmenopause was known and analysis for these years,which controlled for hysterectomy status, did not changethe ®ndings. Strati®ed analysis for women with a historyof surgical menopause showed that the in¯uence of socialclass and region were less strong but in the same direc-tion. In our adjusted model we found no interactionbetween hysterectomy status and social class but theNorth/South difference was greater for those without ahysterectomy (OR� 1.56 (95% CI 1.29 to 1.90) thanamongst those with a hysterectomy (OR� 1.10 (95%CI 0.83 to 1.46), P� 0.18 for interaction)

Women with a history of doctor-diagnosed angina or aheart attack were less likely to use HRT, as were womenwith high cholesterol levels (Table 2). Women withcholesterol levels below 5.2 mmol/L were more thantwice as likely to be users as those with levels above7.8 mmol/L (Table 2). Similarly obese women wereless likely to receive HRT. These ®ndings were notaffected by adjustment for socio-demographic factors orhistory of surgical menopause. Adjustment for bodyweight and history of heart disease did not explain therelationship between cholesterol levels and use ofhormone replacement therapy. In contrast, self-reportedsymptoms or risk factors for heart disease were not asso-ciated with hormone replacement therapy (Table 2).

Women with psychological symptoms on the GeneralHealth Questionnaire 12 and those who reported stresswas affecting their health were more likely to usehormone replacement therapy (Table 3). Women with along-standing illness or contact with a doctor in the lasttwo weeks were also more likely to be users of hormonereplacement therapy (Table 3). These associations werestronger after adjustment for socio-demographic factorsbut addition of hysterectomy status to the model reducedsome of the effects. In the fully adjusted model for 1993/4, including reported surgical menopause, use ofhormone replacement therapy was still signi®cantly asso-ciated with psychological symptoms, stress, self±reported health and contact with a doctor (Table 3).

270 S. SHAH ET AL.

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HRT USE BY CLASS, REGION AND PSYCHOLOGICAL 271

Table 1. Socio-demographic factors and HRT use.

Adjusted for age Adjusted for socio-demographic

factorsa

Adjusted for socio-demographic

factorsa and surgical menopause

(1993 & 1994 only)

n OR (95% CI) n OR (95% CI) n OR (95% CI)

Social class

I 1 II 3480 1.58 (1.38 to 1.81) 3432 1.47 (1.26 to 1.72) 1678 1.51 (1.20 to 1.91)

IIInm 4635 1.40 (1.23 to 1.59) 4585 1.28 (1.11 to 1.47) 2185 1.31 (1.06 to 1.62)

IIIm 1125 1.04 (0.84 to 1.28) 1099 1.02 (0.82 to 1.26) 516 1.00 (0.72 to 1.39)

IV 1 V 3695 1.0 3646 1.0 1776 1.0

Surgical menopauseb Yes 1140 3.14 (2.67 to 3.70) 1105 3.18 (2.68 to 3.76) - -

No 5213 1.0 5050 1.0 - -

Employment

Working 6955 1.0 6863 1.0 3339 1.0

Unemployed 286 0.79 (0.57 to 1.11) 278 0.88 (0.62 to 1.24) 139 0.79 (0.46 to 1.37)

Not working 5973 0.81 (0.72 to 0.90) 5621 0.89 (0.79 to 1.01) 2677 0.84 (0.69 to 1.01)

School leaving age

Under 16 7116 1.0 6935 1.0 3421 1.0

16 or over 5980 1.11 (1.00 to 1.23) 5827 0.92 (0.82 to 1.03) 2734 1.03 (0.87 to 1.23)

Car access

No 2404 1.0 2275 1.0 1090 1.0

Yes 10800 1.58 (1.36 to 1.85) 10487 1.19 (0.99 to 1.44) 5065 1.02 (0.77 to 1.35)

Housing tenure

Owner occupier 10560 1.0 10267 1.0 4940 1.0

Council tenant 2042 0.68 (0.58 to 0.79) 1925 0.89 (0.74 to 1.07) 938 0.82 (0.62 to 1.08)

Private tenant 592 0.86 (0.67 to 1.10) 570 0.89 (0.69 to 1.15) 277 0.71 (0.47 to 1.08)

Income support recipient No 11479 1.0 11209 1.0 5406 1.0

Yes 1699 0.75 (0.63 to 0.88) 1553 1.00 (0.83 to 1.21) 749 1.08 (0.82 to 1.42)

Ethnicity

White 12655 1.0 12344 1.0 5953 1.0

ISC 242 0.56 (0.35 to 0.89) 165 0.71 (0.42 to 1.21) 76 0.96 (0.46 to 1.37)

Black 158 0.45 (0.25 to 0.83) 145 0.55 (0.30 to 1.01) 76 0.27 (0.10 to 0.78)

Other 121 0.86 (0.50 to 1.48) 108 0.93 (0.53 to 1.65) 50 1.27 (0.57 to 2.84)

Marital status

Married 10075 1.0 9756 1.0 4699 1.0

Single 535 0.47 (0.34 to 0.66) 515 0.41 (0.28 to 0.60) 252 0.48 (0.27 to 0.85)

Widowed 1207 0.55 (0.44 to 0.70) 1157 0.53 (0.40 to 0.71) 564 0.59 (0.38 to 0.91)

Divorced/separated 1392 0.98 (0.84 to 1.15) 1334 0.96 (0.77 to 1.19) 640 1.06 (0.78 to 1.45)

Living alone No 11416 1.0 11017 1.0 5340 1.0

Yes 1798 0.86 (0.73 to 1.01) 1745 1.27 (1.00 to 1.62) 815 0.89 (0.62 to 1.29)

NHS region

North & York 1902 1.0 1845 1.0 901 1.0

NW 1794 1.21 (0.99 to 1.48) 1744 1.25 (1.02 to 1.54) 870 1.24 (0.90 to 1.70)

Trent 1337 1.16 (0.93 to 1.45) 1292 1.20 (0.95 to 1.50) 625 1.19 (0.84 to 1.69)

West Midlands 1339 1.22 (0.98 to 1.51) 1300 1.25 (1.00 to 1.56) 634 1.59 (1.14 to 2.21)

Anglia & Oxford 1461 1.59 (1.30 to 1.95) 1417 1.56 (1.26 to 1.92) 640 1.81 (1.32 to 2.49)

N Thames 1657 1.45 (1.19 to 1.77) 1565 1.54 (1.25 to 1.89) 740 1.59 (1.15 to 2.19)

S Thames 1808 1.64 (1.35 to 1.99) 1733 1.64 (1.34 to 2.00) 858 1.62 (1.19 to 2.20)

South West 1916 1.64 (1.35 to 1.99) 1866 1.59 (1.31 to 1.93) 887 1.78 (1.32 to 2.41)

Urbanc

Urban 7345 1.0 7056 1.0 2216 1.0

Rural 2507 1.33 (1.18 to 1.51) 2424 1.24 (1.09 to 142) 705 1.14 (0.88 to 1.47)

North/Southd

North 6372 1.0 6181 1.0 3030 1.0

South 6842 1.39 (1.25 to 1.53) 6581 1.36 (1.23 to 1.51) 3125 1.38 (1.18 to 1.62)

a Age, social class, region, ethnicity, marital status, education, living alone, car ownership, tenure, whether on income support, employment status.b Available for survey years 1993, 1994 only.c Available for survey years 1994, 1995, 1996.d South includes the NHS regions of Anglia & Oxford, North Thames, South Thames, South West.

q RCOG 2001 Br J Obstet Gynaecol 108, pp. 269±275

Psychological symptoms or contact with a doctor did notexplain the relationship between use of HRT and doctor-diagnosed heart disease or cholesterol levels.

DISCUSSION

In this study we have described patterns of use ofhormone replacement therapy in a large representativesample of English women. Large inequalities in useexist in relation to social class, region and ethnicity.We have also found that women with a history of ischae-mic heart disease and women with high cholesterol levelsare less likely to receive HRT. Women with psychologi-cal symptoms and those who have seen a doctor recentlyare more likely to use HRT.

Our study addressed two of the major problems withmost existing UK studies which are either too small todetect important differences or have studied unrepresen-tative populations. Also, previous studies have not beenable to report on regional variations. Furthermore, wehave been able to look simultaneously at a range ofsocio-demographic factors, ischaemic heart disease riskand psychological state.

Before considering the interpretation and implications

of our ®ndings, we will address some potential weak-nesses with our study design.

Study design issues

Women were included in our analysis if their hormonereplacement therapy status was known as a result of parti-cipation in the nurse-administered schedule of the HealthSurvey for England. This was 87% of those who took partin the initial survey. Social class and lifestyle differencesbetween participants and non-participants were small andwould only be important if participation was also asso-ciated with use of HRT. Social class was de®ned usingthe woman's occupation. Analysis using the husband'soccupation made little difference to the results.

The main problem with our study is its cross sectionaldesign. This means that the direction of effects describedis not always certain. This is irrelevant for socio-demo-graphic factors, such as social class or region, but is animportant issue for the interpretation of ®ndings on cardi-ovascular risk and psychosocial factors.

Adjusted analyses controlled for a range of factorswhich previous studies and our own analysis suggestare important determinants of HRT use. The rationalefor including the full range of social variables in the

272 S. SHAH ET AL.

Table 2. HRT use and risk factors for ischaemic heart disease. BMI� body mass index; IHD� ischaemic heart disease.

Adjusted for age only Adjusted for socio-demographic factorsa and

surgical menopause (1993 & 1994 Only)

n OR (95% CI) n OR (95%CI)

Doctor diagnosed IHDb

No 6209 1.0 5904 1.0

Yes 279 0.60 (0.38 to 0.95) 251 0.58 (0.36 to 0.96)

Cholesterolb mmol/L

,5.2 964 1.0 921 1.0

5.2-6.5 2319 0.76 (0.61 to 0.94) 2187 0.73 (0.58 to 0.93)

6.5-7.8 1535 0.73 (0.57 to 0.93) 1465 0.69 (0.54 to 0.90)

.7.8 665 0.40 (0.28 to 0.57) 630 0.39 (0.27 to 0.57)

BMI

20-25 4819 1.0 2395 1.0

,20 449 0.83 (0.62 to 1.13) 201 0.68 (0.40 to 1.14)

25-30 4745 0.98 (0.88 to 1.10) 2197 1.01 (0.85 to 1.21)

.30 2698 0.69 (0.60 to 0.80) 1209 0.80 (0.63 to 1.00)

Symptoms of IHD (Rose

Angina Questionnaire)b

No 5942 1.0 5651 1.0

Yes 528 1.02 (0.78 to 1.34) 489 0.99 (0.74 to 1.33)

Diagnosed hypertensionb

No 5066 1.0 4814 1.0

Yes 1422 1.04 (0.87 to 1.25) 1341 0.95 (0.78 to 1.15)

Smoking

No 9845 1.0 4591 1.0

Current 3360 0.93 (0.83 to 1.04) 1555 0.99 (0.82 to 1.19)

Physical activityb

Active 2524 1.0 2415 1.0

Inactive 3964 0.94 (0.81 to 1.09) 3740 0.94 (0.80 to 1.10)

a Age, social class, region, ethnicity, marital status, education, living alone, car ownership, tenure, whether on income support, employment status.b Available for survey years 1993, 1994.

q RCOG 2001 Br J Obstet Gynaecol 108, pp. 269±275

regression model was to attempt to explain the importantvariations in use. Our key ®nding of social class andregional variations were little changed by adjustmentfor other socio-demographic factors. This was also truefor our ®ndings in relation to cardiovascular risk factorsand psychological symptoms. We were only able tocontrol for hysterectomy status for half the sample. Ascontrol for hysterectomy status made little difference tothe ®ndings for the socio-demographic or cardiovascularvariables, we are con®dent that that these ®ndings arevalid for the whole sample.

Comparison with other work

Our ®ndings on socio-demographic variations in use ofHRT are consistent with other studies which have foundrelationships with various measures of socio-economicstatus. We do not believe that regional variations in usein England have been described before although regionalvariations have been found in the USA4,6,18. It is interest-ing that we found no relationship with educational statusthat is often, but not always, reported as a predictor of useof HRT. The large variations in use between ethnicgroups are similar to those found in our previous studyin London and mirror ®ndings in the United States4,10,18.

Our ®nding that women with ischaemic heart diseaseare less likely to use HRT is consistent with otherstudies8. The cross sectional nature of our study makes

interpretation of this ®nding dif®cult, but may re¯ectselection of women without heart disease to receiveHRT. The effect size seen in this study is the same asthat reported in longitudinal observational studies19,20.However, other studies have not found a relationshipbetween HRT use and total cholesterol levels4,5,7,21. Our®ndings are likely to represent selection of women withlow cholesterol to receive HRT as randomised trials ofHRT have shown minimal direct effects on total choles-terol22.

Our ®ndings on psychological symptoms are consis-tent with a previous UK study which showed that womenwho receive HRT are more likely to have a history ofnon-psychotic psychiatric illness8. They are also consis-tent with studies which showed that users of HRT andthose who attend HRT clinics experience high rates ofdepression23,24.

Implications

The large social class and regional differences in HRTuse suggest that women at greatest risk of cardiovasculardisease and premature mortality are least likely to receiveHRT. If observational evidence on the bene®ts of HRT iscorrect, such prescribing will accentuate inequalities inhealth. Furthermore as women from higher social classesare at greater risk of breast cancer, such prescribingpatterns are likely to increase the adverse effects of

HRT USE BY CLASS, REGION AND PSYCHOLOGICAL 273

Table 3. HRT use and psychological symptoms.

Adjusted for age Adjusted for socio-

demographic factorsa

Adjusted for socio-demographic

factorsa and surgical menopause

(1993 & 1994 only)

n OR (95% CI) n OR (95% CI) n OR (95% CI)

GHQ scoreb

No. of psychological 0 5302 1.0 5155 1.0 3416 1.0

symptoms 1-3 2465 1.16 (1.00 to 1.33) 2380 1.19 (1.02 to 1.38) 1534 1.08 (0.89 to 1.30)

41 1755 1.37 (1.18 to 1.60) 1687 1.49 (1.27 to 1.75) 1052 1.33 (1.09 to 1.64)

Stress affecting healthc

Not at all 1930 1.0 1873 1.0 1850 1.0

Slightly 2335 1.21 (1.0 to 1.46) 2261 1.19 (0.98 to 1.44) 2232 1.15 (0.94 to 1.41)

Moderate 1 2111 1.44 (1.19 to 1.73) 2035 1.44 (1.19 to 1.75) 2015 1.31 (1.07 to 1.60)

Longstanding illness

No 6967 1.0 6733 1.0 3334 1.0

Yes 6244 1.28 (1.16 to 1.42) 6026 1.39 (1.26 to 1.55) 2819 1.26 (1.07 to 1.48)

Saw doctor in last 2 weeksc

No 5231 1.0 5054 1.0 4976 1.0

Yes 1180 1.60 (1.34 to 1.90) 1135 1.75 (1.46 to 2.08) 1111 1.67 (1.38 to 2.00)

General health

Very good 4108 1.0 4009 1.0 1953 1.0

Good 5636 1.10 (0.98 to 1.24) 5462 1.19 (1.05 to 1.34) 2629 1.21 (1.01 to 1.46)

Fair 2747 1.12 (0.97 to 1.29) 2621 1.39 (1.19 to 1.62) 1270 1.30 (1.03 to 1.63)

Bad/very bad 714 1.14 (0.91 to 1.44) 661 1.66 (1.29 to 2.13) 294 1.27 (0.85 to 1.92)

a Age, social class, region, ethnicity, marital status, education, living alone, car ownership, tenure, whether on income support, employment status.b Available for survey years 1993, 1994, 1995.c Available for survey years 1993, 1994.

q RCOG 2001 Br J Obstet Gynaecol 108, pp. 269±275

HRT in the population. However, the absence of bene®tfrom HRT in trials on secondary prevention of heartdisease suggests that the need for caution in determiningthe overall public health implications of our ®ndings25,26.

Nevertheless, our ®ndings may re¯ect wider inequal-ities in access to preventative services and the operationof the inverse care law in prescribing in England. Wecannot, from our study, identify the reasons for differ-ences in prescribing, but the role of professional attitudesand variations in access to preventative services, such aswell women clinics, need to be explored. It is also possi-ble prescription costs act as a barrier to use of HRT.

Our ®ndings add to the large observational literaturethat current users of HRT have a lower prevalence ofischaemic heart disease. The unresolved question iswhether this re¯ects selection of women at low risk ofischaemic heart disease for HRT or a direct bene®cialeffect of oestrogen therapy27±29. The relationship betweencholesterol levels and HRT suggests that prescribingpatterns in England do select women at lower risk ofischaemic heart disease. This interpretation is supportedby a recent prospective study in Sweden7. These ®ndingsfurther emphasise the need for randomised control trialevidence on the cardio-protective effects of HRT.

Higher levels of psychological symptoms and stressamong users of HRT may re¯ect either a direct adverseeffect of HRT or a tendency of women with existing orpast psychological distress to use HRT. Other longitu-dinal evidence suggests the latter8. This suggests thatHRT is prescribed to treat psychological symptoms. Ifthese symptoms were caused by distressing physicalsymptoms of the menopause, such as hot ¯ushes ordyspareunia, we would expect them to be relieved byHRT and women on HRTto report a similar or betterpsychological state than non-users. Thus, prescription ofHRT may be a medical response to current or pastpsychological distress among menopausal women. Thisexplanation is further supported by the higher use ofmedical services by users of HRT. Such prescribingwould be reinforced by lay views of HRT as a panaceafor a range of problems experienced in middle age. Thisanalysis cannot comment on the appropriateness of suchprescribing, but suggests the need for further work todetermine whether the management of menopausalwomen with psychological symptoms in primary careis appropriate.

Acknowledgements

The data for this study were provided by The Data

Archive of the University of Essex. The authors would

like to thank the Data Archive and the depositors of the

information for permission to use the data. Material from

the Health Survey for England is Crown Copyright and has

been made available by the Of®ce of National Statistics, the

Joint Health Surveys Unit of Social and Community Plan-

ning Research and the Department of Epidemiology and

Public Health at University College, London. Neither the

depositors nor the Data Archive bear any responsibility for

the analysis or interpretation of the data reported here.

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Accepted 11 October 2000

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q RCOG 2001 Br J Obstet Gynaecol 108, pp. 269±275