Hormone replacement therapy in Norwegian women, 1996–1997☆
Introduction
In the past, Norwegian women were restrictive in their use of estrogens for peri- and postmenopausal symptoms. Compared with women in other Scandinavian countries they appeared to be more sceptical towards hormone replacement therapy (HRT) than many of their neighbouring sisters [1]. Some of this scepticism was probably due to fear of adverse reactions extrapolated from the use of oral contraceptives (OCs), but there also seems to be a reluctance to interfere with the natural process of ageing [2].
During the last 10 years, however, these patterns have changed Fig. 1. According to sales figures, there has been a considerable increase in the sale of estrogens in this period. If sales figures defined daily doses per day (DDD per day) for 1999 provide an reasonable indication of use, more than 200,000 Norwegian women, or approximately 40% of all women between the ages of 45 and 66, are using some kind of estrogens today [3].
In contrast to USA, where conjugated equine estrogens have been and still are the most frequently prescribed estrogen preparation, the Norwegian market is totally dominated by the natural estrogen estradiol, most often used in combination with a progestagen derivative [3]. Norway and Iceland seem to be the only or among the very few of the countries in Europe where conjugated equine estrogens are not at all available. The only medium potency estrogen available in Norway is the natural estrogen estradiol in different combinations and brands.
A study presented in Maturitas last summer [4] showed no significant increase in use of HRT during the period 1994–1998 in spite of a clear increase in the sale.
The Norwegian women and cancer (NOWAC) study, which is the first population study in this field in Norway, gives us the opportunity to have a closer look at prevalence and user patterns and to see whether or not there is an increasing use of HRT among Norwegian women.
Section snippets
Materials and methods
The Norwegian women and cancer study (NOWAC) is a population based, prospective study based on questionnaires mailed to women aged 30–70 years.
This report is based on cross-sectional data for women aged 45–64 years whose names were drawn randomly from the Central Population Register.
Norway has a Central Population Register of all inhabitants including those with temporary residency status. All persons living in Norway have been given a unique identification number, which includes information on
Results
The mean age of the women was 53 years and their mean education 11.6 years. About 60% of the women had a normal BMI, while 30% tended to be overweight and about 9% were obese. A majority of 80% were married or living with a partner.
Table 1 shows that more than 60% of the women were classified as postmenopausal. Less than 25% were premenopausal, 8% perimenopausal, and 7% of the women were unable to decide upon their own menstruation status. These women were classified as ‘uncertain status’, 99%
Methodology
The final response rate was 60%. This could imply a problem with selection bias of which we have two different types. One is the non-coverage type caused by not capturing participants by the actual mechanism of contact. The other is the non-response type, either due to non-completion or unwillingness to participate. In our study the non-coverage problem is almost non-existent (less than 0.5%), as the personal identification number is mandatory in Norway, frequently used for instance by the tax
Concluding remarks
The study shows that prevalence numbers have increased from 1996 to 1997. Our findings confirm estimates based on the sales figures in the same period, which say that almost every third woman between 45 and 64 years was using estrogens per os or trans-cutaneously in Norway in 1996–1997.
High household income, BMI≤30, ever smoking and use of OCs was positively related to HRT use. However, our data seem to indicate that the impact of socio-economic differences on the prevalence of HRT is
References (35)
- et al.
Trends in the use of climacteric and postclimacteric hormones in Nordic countries
Maturitas
(1995) - et al.
Hormone replacement therapy: knowledge, attitudes, self-reported use- and sales figures in Nordic women
Maturitas
(2000) - et al.
Determinants of self rated menopause status
Maturitas
(1997) - et al.
Duration of hormonal replacement therapy in general practice; a follow-up study
Maturitas
(1998) - et al.
Why do postmenopausal women discontinue hormone replacement therapy?
Maturitas
(1999) - et al.
The prevalence of oestrogen replacement therapy in South Australia
Maturitas
(1993) Management of hormone replacement therapy: the Italian experience
Eur. J. Obstet. Gynecol. Reprod. Biol.
(1996)- et al.
Determinants of hormonal replacement therapy in recently postmenopausal women
Eur. J. Obstet. Gynecol. Reprod. Biol.
(1992) - et al.
The climacteric, osteoporosis and hormone replacement; views of women aged 45–49
Maturitas
(1995) - et al.
Mortality decline and widening social inequalities
Lancet
(1986)
Premenopausal determinants of menopausal estrogen use
Prev. Med.
Declining socioeconomic differences in the use of menopausal and postmenopausal hormone therapy in Finland
Maturitas
Hormone replacement therapy and previous use of oral contraceptives among Swedish women
Maturitas
Characteristics of noncontraceptive hormone users
Prev. Med.
Østrogenbehandling [Estrogen replacement]
Tidsskr. Nor. Laegeforen.
Cited by (49)
Changes in Hormone Therapy Prescriptions Among Middle-Aged Women in Taiwan: Implications for Health Needs at Menopause
2011, Women's Health IssuesCitation Excerpt :In European countries, such as the United Kingdom, France, Denmark, Norway, and Sweden, the prevalence rate of HT use among middle-aged women or older exceeded 30% in the late 1990s. After the WHI reports, the rate declined by 15% within 1 year, falling by 40% by 2004 (Bakken, Eggen, & Lund, 2001; Gayet-Ageron et al., 2005; Mishra et al., 2006; Oddens & Boulet, 1997; Thunell, Stadberg, Milson, & Mattsson, 2005). Most of the above-mentioned studies, however, were concerned with HT reduction.
- ☆
The Norwegian women and cancer (NOWAC) study 1996–1997