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Keywords:

  • biliary;
  • bone density;
  • hormone replacement therapy;
  • liver cirrhosis;
  • oestrogen;
  • osteoporosis

Abstract.

  1. Top of page
  2. Abstract.
  3. Introduction
  4. Methods
  5. Dual-energy X-ray absorptiometry
  6. Statistics
  7. Ethics
  8. Results
  9. Discussion
  10. Conflict of interest statement
  11. Acknowledgements
  12. References

Objectives.  The prevalence of osteoporosis amongst patients with primary biliary cirrhosis (PBC) is high and may be a serious clinical problem. Hormone replacement therapy (HRT) is effective in preventing bone loss but has not been evaluated in randomized trials in PBC. The primary aim was to study the effect of transdermal HRT in combination with daily vitamin D and calcium supplementation on bone loss compared with vitamin D and calcium supplementation only in postmenopausal women with PBC. The secondary aim was to study the safety of transdermal HRT.

Subjects/interventions.  Eighteen females with PBC were randomized to receive 2 years therapy with either (i) transdermal oestradiol 50 μg 24 h−1 two times per week + medroxyprogesterone 2.5 mg day−1 + alfacalcidol 0.25 μg day−1 and calcium 1 g day−1 or (ii) alfacalcidol 0.25 μg day−1 and calcium 1 g day−1. Dual-energy X-ray absorptiometry for measurement of bone mineral density (BMD) and sampling of blood and serum for measurements of biochemical markers of liver function was performed before, during and at the end of treatment.

Results.  BMD increased significantly at the lumbar spine (P < 0.05) and the femoral neck (P < 0.05) in the HRT group whereas no significant change was found in the control group. One oestrogen-treated patient was excluded after 1 year because of deteriorating, but reversible, aminotransferases. Dropout frequency because of nonliver-related causes was higher in the HRT group. Otherwise, no difference with respect to adverse liver reactions was found between the groups.

Conclusion.  Transdermal HRT increases BMD in PBC patients with few severe side effects related to the liver.


Introduction

  1. Top of page
  2. Abstract.
  3. Introduction
  4. Methods
  5. Dual-energy X-ray absorptiometry
  6. Statistics
  7. Ethics
  8. Results
  9. Discussion
  10. Conflict of interest statement
  11. Acknowledgements
  12. References

Primary biliary cirrhosis (PBC) is an autoimmune liver disease mostly affecting women. The disease is characterized by a slow but progressive destruction of the bile ducts, chronic cholestasis, development of liver cirrhosis and liver failure in some patients [1–3]. The prevalence of osteoporosis amongst patients with PBC is on average 30% [4–7]. Reports concerning the rate of bone loss in these patients are contradictory and vary between equal to twice as rapid as in age-matched controls without liver disease [6, 8, 9]. Metabolic bone disease, when present in patients with PBC, can contribute to great morbidity and rarely contraindicate a life-saving liver transplantation [8]. The pathogenesis of osteoporosis in PBC is unknown and both high turnover and low turnover osteoporosis have been suggested [5, 10–12]. Histomorphometric changes resemble those of peri-postmenopausal osteoporosis [10, 12] and some claim that osteoporosis in PBC is the same as postmenopausal osteoporosis [6, 10].

The recommended management of osteoporosis and prevention of bone loss in PBC includes vitamin D and calcium supplementation, bisphosphonates, fluorides or oestrogen [13–16]. The documentation of these treatments in randomized studies in PBC patients, however, is scarce.

Two randomized studies with bisphosphonate treatment and with conflicting results have appeared [17, 18]. Beneficial effects on bone mineral density (BMD) in PBC after oestrogen therapy have been reported previously [16, 19, 20]. The patients seemed to tolerate oestrogen treatment well. These studies, however, were retrospective studies or not randomized trials with the risk for selection bias. Oestrogen replacement given orally might theoretically worsen the liver disease by inducing a lithogenic bile which is not the case with transdermal oestrogen [21]. Oestrogen given transdermally seems to have less metabolic effects on the liver [22, 23] making this route of administration potentially safer in patients with chronic liver disease. Transdermal oestrogen in doses of 50–100 μg given to postmenopausal women without liver disease increases BMD by 3–5% per year as measured with bone densitometry at the lumbar spine level with somewhat less effect at the femoral neck [24–26]. The effect of transdermal oestrogen was comparable to oral oestrogen [26] and decreased bone loss in postmenopausal liver transplant women [27]. However, no randomized trials of transdermal oestrogen therapy to prevent bone loss in PBC have been reported.

The primary aim was to study the effect on bone loss (ΔBMD per year) of transdermal hormone replacement therapy (HRT) in combination with daily vitamin D and calcium supplementation compared with daily vitamin D and calcium supplementation only in postmenopausal women with PBC.

The secondary aim was to study the safety of transdermal HRT with respect to the liver disease in patients with PBC.

Methods

  1. Top of page
  2. Abstract.
  3. Introduction
  4. Methods
  5. Dual-energy X-ray absorptiometry
  6. Statistics
  7. Ethics
  8. Results
  9. Discussion
  10. Conflict of interest statement
  11. Acknowledgements
  12. References

Five centres were invited to participate (University hospitals of Karolinska, Huddinge, Umeå, Uppsala and Örebro). These had together about 250 PBC patients in their files at the planning of the study.

Postmenopausal women between the age of 40 and 70 years with the diagnosis of PBC and Child-Pugh score A [28] were recruited for the study. The minimum criteria for the diagnosis of PBC were presence of anti-mitochondrial antibodies and liver histopathology compatible with PBC. Postmenopausal status was defined as loss of menstruations for at least 1 year and elevated follicle-stimulating hormone (FSH) compatible with a postmenopausal status.

Exclusion criteria were other bone disorders than osteoporosis related to liver disease or postmenopausal status, history of cancer, unexplained vaginal bleeding, unexplained uterus enlargement or lump in the breasts, history of thromboembolic disorder, hyperthyroidism, impairment of the renal function, severe heart disease, uncontrolled hypertension (diastolic blood pressure > 100 mmHg) and history of drug or alcohol abuse.

The patients should not have been treated with calcitonin, high-dose vitamin D (more than 50 000 IU weekly), systemic corticosteroids, high-dose heparin, oestrogen (except for local preparations not containing oestradiol), progestagens, fluorides or bisphosphonates.

The patients were screened after they had given informed consent to participate. Screening included medical history including past and present pharmacotherapy according to a standardized questionnaire, physical examination, blood and serum biochemistry, urine analyses, TSH, T4 and FSH. In addition, mammography was performed, unless performed within the preceding 12 months.

Patients who fulfilled the inclusion and exclusion criteria were examined with dual-energy X-ray absorptiometry (DXA) at the lumbar spine and the femoral neck (see below). Clinical X-ray of the lumbar spine was performed unless performed within the previous 12 months.

The patients were randomized to transdermal HRT (oestradiol patch, 50 μg 24 h−1 twice weekly (Estraderm®, Novartis Pharma AG, Stein, Switzerland) in combination with medroxyprogesterone (Gestapuran®, Leo Pharmaceuticals, Ballerup, Denmark) for 24 months or no hormone supplementation. Randomization was performed with sealed envelopes containing the allocation to either of the treatment groups. A stratification was made with respect to the presence or absence of osteoporosis defined according to the definition by the WHO as a T-score of <2.5 SD [29]. The women who were randomized to HRT were referred for gynaecological examination and instructed by the gynaecologist how to use the hormonal study medication before start of the therapy. Women over 60 years of age started with Estraderm® 25 μg 24 h−1 and increased the dose to 50 μg 24 h−1 after 3 months. The dose of medroxyprogesterone was 10 mg day−1 12 days month−1 if less than 2 years from menopause or 2.5 mg day−1 continuously if more than 2 years from menopause.

Both groups received supplementation with vitamin D (alfacalcidol 0.25 μg day−1(Etalpha®, Leo Pharmaceuticals, Ballerup, Denmark) and calcium (Calcium-Sandoz®, Novartis Pharma SA, Orleon, France) 1 g day−1.

The baseline measurements and visits at 1, 3, 12 and 24 months included medical history including experiences of adverse reactions, questioning of therapy compliance, physical examination and blood and serum biochemistry and urine analyses as above. In addition, DXA examinations at the lumbar spine and the femoral neck were performed after 12 and 24 months.

Any increase on bilirubin, alkaline phosphatases or aminotransferases of 100% or more above baseline values or an increase in bilirubin to ≥100 μmol L−1 was considered as intolerability.

Dual-energy X-ray absorptiometry

  1. Top of page
  2. Abstract.
  3. Introduction
  4. Methods
  5. Dual-energy X-ray absorptiometry
  6. Statistics
  7. Ethics
  8. Results
  9. Discussion
  10. Conflict of interest statement
  11. Acknowledgements
  12. References

The investigations were performed with Lunar DPX-LTM (Lunar Co., Madison, WI, USA) scanners at screening and after 12 and 24 months of treatment. The mean BMD value of the second, third and fourth lumbar vertebrae (lumbar spine BMD) and of the femoral neck (femoral neck BMD) were used in the present study.

Statistics

  1. Top of page
  2. Abstract.
  3. Introduction
  4. Methods
  5. Dual-energy X-ray absorptiometry
  6. Statistics
  7. Ethics
  8. Results
  9. Discussion
  10. Conflict of interest statement
  11. Acknowledgements
  12. References

The primary efficacy variable was rate of bone loss (g cm2 year−1) at the lumbar spine and the femoral neck as determined by DXA measurements. The sample size calculation was based on an earlier report where fluoride treatment versus placebo in PBC showed a bone loss rate of 3.3% per year in the control group and an increase of 1.5% during therapy with fluorides [30]. Based on these figures and assuming a significance level of 0.05 and a power of 0.8 and compensating for a dropout frequency of 20%, 40 patients were needed.

Wilcoxon signed rank test was used for comparison of related variables. Mann–Whitney U-test was used for group comparisons. Values are presented as median (range).

Ethics

  1. Top of page
  2. Abstract.
  3. Introduction
  4. Methods
  5. Dual-energy X-ray absorptiometry
  6. Statistics
  7. Ethics
  8. Results
  9. Discussion
  10. Conflict of interest statement
  11. Acknowledgements
  12. References

The study was approved by the Ethics Committees of Uppsala University, Karolinska Institute, University of Linköping and Umeå University.

Results

  1. Top of page
  2. Abstract.
  3. Introduction
  4. Methods
  5. Dual-energy X-ray absorptiometry
  6. Statistics
  7. Ethics
  8. Results
  9. Discussion
  10. Conflict of interest statement
  11. Acknowledgements
  12. References

The patients were recruited from 1997 to the end of 1999. Until that time only 18 PBC patients had been randomized into the study. The main reason was that many had previously received oestrogen treatment or treatment with systemic corticosteroids for different reasons, which became apparent during screening, and were excluded from participation in the study. Thus, it was decided to end the recruitment prematurely at the end of 1999.

The baseline characteristics of the randomized patients are presented in Table 1. The prevalence of osteoporosis was higher amongst patients not receiving oestrogen (four of 10 compared with two of eight patients). Lumbar X-ray did not show any fractures in 17 of 18 patients. The remaining patient was not willing to undergo the examination.

Table 1.  Patient data
 Oestrogen + vitD + Ca (n = 8)VitD + Ca (n = 10)
  1. Values excepting the final row are presented as median (range).

Age, years57 (52–68)57 (52–67)
Years since diagnosis 4 (1–25) 5 (1–17)
Bilirubin at baseline, μmol L−110 (7–43) 9 (6–22)
ALT at baseline, μkat L−1 0.89 (0.50–2.40) 0.97 (0.40–3.30)
Alk.phosphatase at baseline, μkat L−1 7.9 (3.4–38.0)10.5 (4.7–26.3)
Albumin at baseline, g L−142 (35–44)43 (40–45)
Osteoporosis, no. of patients (lumbar spine and/or femoral neck) 2 4

A within-group comparison (Wilcoxon signed rank test) showed a significant increase in lumbar (P = 0.046) and femoral neck (P = 0.028) BMD in the HRT group. The corresponding values for the control group were a nonsignificant increase at the lumbar spine (P = 0.114) and a nonsignificant decrease at the femoral neck (P = 0.086).

Femoral neck BMD decreased over time in those who did not receive HRT, −0.0054 (range −0.0318 to 0.0389) g cm2 year−1, whereas the corresponding value increased in those who received HRT, 0.0140 (range 0.0104–0.0389) g cm2 year−1 (P = 0.005). Lumbar spine BMD increased over time in the control group, 0.0114 (range −0.0420 to 0.0795) g cm2 year−1 and three times more in the HRT group, 0.0326 (range −0.0032 to 0.0795) g cm2 year−1, but the difference was not statistically significant (P = 0.051). Figure 1 shows the relative change in the lumbar spine and the femoral neck BMD over time (ΔBMD year−1 as percentage of BMD at baseline) for both treatment groups. BMD at the femoral neck decreased by −0.6 (range −3.6 to 3.0)% year−1 in the control group and increased by 1.7 (range 1.2 to 4.4)% year−1 in the HRT group (P = 0.007). The corresponding values for the rate of lumbar BMD change over time for the control and hormonal treatment group was 1.0 (range −4.7 to 3.0) and 3.1 (range −0.3 to 11.3)% year−1, respectively (P = 0.051).

image

Figure 1. Relative change per year of lumbar and femoral neck bone mineral density (BMD). The box plot is based on the median, quartiles and extreme values. P-values for the comparison between intervention and control group are shown.

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Three patients dropped out in the HRT group (Fig. 2). One female stopped using the patches after 4 weeks because of temporary, spotty vaginal bleedings. The second female had a slight increase in systolic blood pressure after 3 months (150 mmHg) and did not want to continue. The third woman had increased AST (three times above baseline) and ALT values (five times above baseline) and was withdrawn. Bilirubin and alkaline phosphatases were not increased over baseline in this woman. AST and ALT returned to baseline values within 3 months after withdrawal. This woman did not experience any symptoms and had not taken any other drug except for famotidine on demand. No other cause, except for the oestrogen treatment, was disclosed as an explanation for the liver reaction. Except for these three cases, the transdermal oestrogen therapy was well tolerated.

image

Figure 2. Schedule of the trial.

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One woman in the control group was withdrawn after 12 months when her bilirubin levels had increased to 89 μmol L−1 (>100% over baseline). AST, ALT and alkaline phosphatase levels were unchanged compared with baseline values. This woman had a further increase in bilirubin and developed ascites within the following 6 months.

The relative change of bilirubin, AST, ALT, alkaline phosphatases and albumin over baseline values did not differ when the two treatment groups were compared (Table 2).

Table 2.  Relative change in liver biochemistry during treatment
 Maximum change% from baseline value Median (range)P
Oestrogen + vitD  + Ca (n = 7)VitD + Ca (n = 10)
Bilirubin38 (5 to 83)33 (−5 to 107)NS
ALT−5 (−24 to 483)8 (−7 to 140)NS
Alk. phosphatase−4 (−34 to 29)−2 (−10 to 35)NS
Albumin−5 (−12 to 0)−5 (−14 to 5)NS

Discussion

  1. Top of page
  2. Abstract.
  3. Introduction
  4. Methods
  5. Dual-energy X-ray absorptiometry
  6. Statistics
  7. Ethics
  8. Results
  9. Discussion
  10. Conflict of interest statement
  11. Acknowledgements
  12. References

Hormone replacement therapy with transdermal oestrogen twice weekly in combination with progesterone increased BMD in PBC patients significantly compared with vitamin D and calcium supplementation only. The difference between the groups was most prominent at the femoral neck where BMD increased by 2% year−1 whereas in those who did not receive HRT the bone loss was on average 1% year−1. BMD increased at the lumbar spine as well during hormonal supplementation by 3% year−1 and in the control group by 1% year−1. The difference at the lumbar spine did not reach statistical significance, probably explained by the low power of this study, which was originally designed to include 40 patients.

In spite of the fact that only half of the planned patients were recruited an obvious effect of transdermal HRT on BMD was detected. This is in accordance with previous nonrandomized studies suggesting that oestrogen treatment is effective in reducing bone loss in PBC. These studies, however, are hampered by selection bias, e.g. comparing osteoporotic (therapy) versus nonosteoporotic (control) PBC patients [20] or were based on retrospective data [7, 19].

Oestrogen treatment was well tolerated by PBC patients and liver transplanted patients according to previous reports [7, 16, 19, 20, 31]. However, three of eight women in the present study withdrew because of side effects. One of these had an obvious increase in AST and ALT probably caused by oestrogen. One female in the control group was also withdrawn as she became icteric. This woman was classified as Child A class (score 5) prior to the study but had probably more advanced disease which progressed during follow-up. This assumption was also supported during the clinical follow-up of this patient.

The other withdrawals, slightly increased blood pressure and vaginal spot bleedings, respectively, were according to the patient's wishes to stop treatment because of their concerns. In the remaining patients HRT was well tolerated. Our relative high dropout frequency during HRT is in accordance with previous reports from treatment in postmenopausal women [32, 33]. The high dropout frequency limits the usefulness of oestrogen for maintenance therapy in PBC. The corresponding dropout frequency for bisphosphonates are reported to be less [34, 35]. Thus, this speaks in favour of bisphosphonates as treatment when bone loss in PBC patients progresses in spite of vitamin D and calcium supplementation. In addition, recent reports concerning HRT indicate that the risk/benefit balance is not favourable for HRT as first line treatment for the prevention of bone loss [36, 37].

Hepatic safety during oestrogen therapy in PBC can probably be managed by regular serum biochemistry sampling during treatment but follow-up is needed for long time as the reaction may come as late as after 1 year.

One of the main reasons for the low recruitment into the study was that many of the women with PBC had been prescribed oestrogen treatment by their family doctors or gynaecologists and consequently were not eligible for the study. This was surprising as we thought that the presence of liver disease in these patients should make the prescribing doctors more reluctant to use oestrogens because of safety concerns. To our knowledge, no reports are available concerning the prevalence of oestrogen prescriptions amongst PBC patients. Prescription of oestrogen to treat or prevent osteoporosis in this patient group, however, seems to be infrequent [38].

Acknowledgements

  1. Top of page
  2. Abstract.
  3. Introduction
  4. Methods
  5. Dual-energy X-ray absorptiometry
  6. Statistics
  7. Ethics
  8. Results
  9. Discussion
  10. Conflict of interest statement
  11. Acknowledgements
  12. References

Members of the Swedish Internal Medicine Liver Club (SILK). Hanna Sandberg-Gertzén, Åke Danielsson. Novartis for sponsorship.

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  1. Top of page
  2. Abstract.
  3. Introduction
  4. Methods
  5. Dual-energy X-ray absorptiometry
  6. Statistics
  7. Ethics
  8. Results
  9. Discussion
  10. Conflict of interest statement
  11. Acknowledgements
  12. References
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