783

a real dilemma about the relative and interventional treatment. of medical advantages

there is still

PJS, Keen H, Reid DD, McCartney P, Jarrett RJ. Myocardial ischaemia, risk factors and death from coronary heart

1. Rose G, Hamilton

2.

disease. Lancet 1977; i: 105-09. Shaper AG, Cook DG, Walker M, MacFarlane PW. Prevalence of ischaemic heart disease in middle aged British men. Br Heart J 1984;

51: 595-605. 3. Cannon PJ, Connell PA, Stockley IH, Garner ST, Hampton JR. Prevalence of angina as assessed by a survey of prescriptions for nitrates. Lancet 1988; i: 979-81. 4. Report from the V. A. Cooperative Coronary Surgery Study. Effect of coronary bypass surgery on longevity in high and low risk patients. Lancet 1977; ii: 1243-45. 5. European Coronary Surgery Study Group. Long-term results of prospective randomised study of coronary artery bypass surgery in stable angina pectoris. Lancet 1982; ii: 1173-80. 6. CASS Principal Investigators and their Associates. Coronary artery surgery study (CASS): a randomized trial of coronary artery bypass surgery. Survival data. Circulation 1983; 68: 939-50. 7. Parisi AF, Folland ED, Hartigan P. A comparison of angioplasty with medical therapy in the treatment of single-vessel coronary artery disease. N Engl J Med 1992; 326: 10-16. 8. Norell M, Lythall D, Coghlan G, et al. Limited value of the resting electrocardiogram in assessing patients with recent onset chest pain: lessons from a chest pain clinic. Br Heart J 1992; 67: 53-56. 9. Italian CNR Multicentre Prospective Study Group. Long-term survival in medically treated patients with ischaemic heart disease and prognostic importance of clinical and electrocardiographic data. Eur Heart J 1989; 10: 292-303. 10. Henderson RA. The current practice of coronary arteriography in the UK: the RITA trial coronary arteriogram register. Br Heart J (in press).

Does infection occur with modern intrauterine devices? The commonest reason for discontinuing use of an intrauterine device (IUD) is increased menstrual blood loss.1 However, investigators have also been worried about the possibility of an increased risk of pelvic inflammatory disease. An underlying difficulty is the confusion surrounding the diagnosis of PID. and Simple clinical features are not always predictive 1 can have low specificity and sensitivity. Some laboratory tests—eg, C-reactive protein and the erythrocyte sedimentation rate-can help but the gold standard for assessment of tubal involvement is laparoscopic verification. In 1970, the ninth report of the Cooperative Statistical Programme2 reviewed the incidence of pelvic sepsis with the IUDs used in that programme. The 2-year combined rates were 3-8-5-2 per 100 women for Lippes loops, bows, steel rings, and coils. At that time WHO,3 the US Advisory Committee on Obstetrics and Gynecology,4and the American College of Obstetricians and Gynecologistss all concluded that PID was not an important complication of IUD use. They also stated that many of these infections were minor in nature and could be treated with the IUD in situ. During the 1970s there was a massive increase in sexually transmitted diseases, largely attributable to gonococcal infection and Chlamydia trachomatis.s5 Although the incidence of PID correlated strongly with the prevalence of sexually transmitted diseases,66 it was impossible to ascertain the contribution of factors such as attitudes to sexuality, numbers of

sexual partners, knowledge about sexually transmitted diseases, and legal abortions.’At the same time, there was a general increase in the use of IUDs, especially of copper-releasing devices, and not surprisingly some people linked the increasing rate of PID to the growing use ofIUDs.1 The prevailing view was that the background rate of PID in the general population was about 1 % per annum.Early work8,9 had indicated a higher risk of PID in IUD users, but use of inappropriate controls biased the results. These reports also showed that combined oral contraceptive pills protected against PID. By 1987, the overall impression was that there was at least a 2-fold increase risk of PID; the risk seemed to be higher within 30 days of IUD insertion.10 However, there were many

methodological difficulties with these investigations, with bias towards overdiagnosis. Struthers" subsequently reviewed these early accounts and concluded that in some twenty-eight articles including 25 674 women, of whom 42-5% were nulliparous, the overall PID rate was 1 49/100-woman-years—ie, lower than first thought. The largest database for IUD studies with random allocation multicentre comparison of devices is that collected by WHOY In this issue (p 785) Farley and colleagues show that there is only a slight risk of PID during the first 20 days post-insertion and thereafter there is little difference between rates in IUD users and the background population. This international database included 22 908 IUD insertions and more than half a million cycles of use (51 399 woman-years). After the first 20 days the risk was low and remained constant for up to 8 years of follow-up. Rates varied with geographical area, and inversely with age. Rates were lower in women who had had IUDs inserted after 1980 (62% lower). The findings also indicate that the PID rate is related to the background risk of sexually transmitted diseases. Other studies13,14 have likewise shown a low risk, Cramer et al13 showed that, in women having only one sexual partner, there was no increased risk of primary tubal infertility associated with IUD use, and Daling et ap4 found that the lowest risk of getting tubal infertility was associated with the use of a copper IUD. Two studies have followed up patients who had had IUDs removed for medical reasons; both are reassuring since they show no impairment of fertility, even when the IUD was removed for pain and/or bleeding, expulsion, or

"other medical" reasons.1S,16 The transient increased risk during the first 20 days of use may be associated with the insertion procedure. Thus it is essential that all patients should be adequately assessed before the fitting of an IUD, and that it should be fitted under strict aseptic control. To reduce the risk associated with insertion, the devices should be left in place for as long as possible. In terms of contraceptive efficacy, Newton and Tacchp7 showed that extended use was safe for all modern IUDs. The Copper T 380 series and Multiload 375 devices can safely remain in place for at least 8 years

784

replacement is necessary, as can the 20g/day levonorgestrel IUD. 5 years is recommended for the

before

Nova T because the pregnancy

rate

increases

subsequently. 12 For multiparous women and nulliparous women in low-risk groups, there seems to be little if any risk of getting PID with modern copper-releasing IUDs and the 20 fig/day levonorgestrel IUD. If a patient in a high-risk group needs to use an IUD, a copperreleasing or a levonorgestrel-releasing device can be prescribed, after counselling. The levonorgestrel IUD will offer some protection against PID: the rate, at 5 years of use, is less than 1 per 100 woman-years. In all cases medicated devices releasing copper or levonorgestrel are preferable to the older nonmedicated devices. 1. WHO Scientific Group. Mechanism of action safety and efficacy of IUDs. Geneva: WHO, 1987. 2. WHO. IUDs: physiological and clinical aspects. WHO Tech Rep Ser 1968; 397: 21. 3. Advisory Committee on Obstetrics and Gynecology. Report on IUDs. Washington, DC: US Food and Drug Administration, 1968. 4. American College of Obstetricians and Gynecologists. The IUD. ACOG Tech Bull 1968; 10. 5. Kessel E. PID with IUD use: a reassessment. Fertil Steril 1989; 51: 1-11. 6. Westrom L. PID bacteriology and sequelae. Contraception 1987; 36: 111-28. 7. Westrom L. PID and other STDs. Curr Sci 1989; 1: 5-10. 8. Wright NH, Leemmle P. Acute PID in an indigent population. Am J Obstet Gynecol 1968; 101: 979-90. 9. Westrom L, Bengtsson LP, Mardh DA. The nsk of pelvic inflammatory disease in women using intrauterine contraceptive devices as compared to non-users. Lancet 1976; ii: 221-24. 10. Grimes DA. IUD and PID: recent developments. Contraception 1987; 36: 97-109. 11. Struthers B. IUDs, PID and fertility in nulliparous women. Adv Contraception 1990; 7: 211-30. 12. WHO Task Force Report: The T Cu 380A, Multiload 250 and Nova T IUDs at 3, 5, and 7 years of use. Contraception 1990; 42: 142-58. 13. Cramer D, Schiff I, Schoenbaum SC, et al. Tubal infertility and IUDs. N Engl J Med 1985; 312: 941-47. 14. Daling JR, Weiss NS, Metch BJ, et al. Primary tubal infertility in relation to IUD use. N Engl J Med 1985; 312: 937-41. 15. Wilson JC. A prospective New Zealand study of fertility after removal of copper IUDs: a four year study. Am J Obstet Gynecol 1989; 160: 391-96. 16. Sandmire HF. Fertility after IUD discontinuation. Adv Contraception 1986; 2: 327-35. 17. Newton JR, Tacchi D. Long-term use of IUDs. Lancet 1990; 335: 1322-23.

Protecting individuals; preserving data information technology led to widespread public concern about privacy and data protection. Soon we were awash with publications and consultative documents containing numerous recommendations for standards of practice. The content and style of these pronouncements depended on their derivation, whether from a professional or government body, or from a medical or non-medical background. Naturally they tended to relate to prevailing national mores. Many specifically considered the questions raised by the need for the public good, particularly for medical research, whether clinical or epidemiological. Perhaps the most scholarly was the report of a working party set up by Advances

in

the Commission of the European Communities chaired by E. G. Knox.’ It is therefore especially unfortunate that a draft EC directive2 currently circulating for consultation should be formulated in such a way that it could, if implemented, lead to the rapid demise of much of the epidemiological (and social science) research in the Community.3This draft directive is proposed despite the Commission’s endorsement of the 1981 Data Protection Convention of the Council of Europe, the justification given being that only seven members (including the UK) have ratified it and passed domestic legislation. The Commission concludes that, without a further directive, equivalent protection between member states is insufficient. The dangers in the document stem from its heavy legal overtones. Standards concerning the use of personal data are based on the levels prevailing in the most restrictive states. Moreover, the authors seem to have totally ignored the needs of the public health for epidemiological and much other research. Take this sweeping general caveat: "member states shall prohibit the automatic processing of data revealing ethnic or racial origin ... and of data regarding health or sexual life, without the express and written consent, freely given, of the data subject". An important and damaging principle sets out that personal data should be "kept in a form which permits identification of the data subjects for no longer than is necessary for the purpose for which the data were stored.". The restrictive nature of these proposals could rule out the release of cancer information to regional cancer registries and thus effectively sabotage the large body of research they generate into causes of cancer and evaluation of the effectiveness and safety of treatment. This would be in line with with the prevailing policy in Germany, for example, where cancer registration is severely restricted. It would also render impossible retrospective studies of health records. Those who are consulted must point out the real dangers in these proposals and insist on a reformulation that permits the continuation of epidemiological research. A study of the wording suggests that this could be readily achieved by exempting medical research that is conducted under strict ethical safeguards. Medical communities in member states are already conscious of the need to safeguard both privacy and confidentiality. In the UK a group set up by the Royal College of Physicians is preparing a report on ethical safeguards; we hope this will provide guidelines to help exempt medical research from the damaging proposals in the directive. 1. Knox EG. The

2.

3.

confidentiality of medical records: the principles and practice of protection in a research-dependent environment. Report of working party of Advisory Panel for Social Medicine and Epidemiology in European Economic Community. Luxembourg: Commission of the European Communities, 1984. Proposal for an EC Council Directive concerning the protection of individuals in relation to the processing of personal data. Syn 287. Brussels, 1992. Knox EG. Confidential medical records and epidemiological research. Br Med J 1992; 304: 727-28.

Does infection occur with modern intrauterine devices?

It is difficult to determine if the IUD increases the risk of pelvic inflammatory disease (PID) because simple clinical features are not consistently ...
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