Systemic lupus erythematosus prevalence in the UK: methodological issues when using the General Practice Research Database to estimate frequency of chronic relapsing-remitting disease.

PURPOSE: The purpose of this study was to calculate the prevalence of systemic lupus erythematosus (SLE) between 1992 and 1998 using the General Practice Research Database (GPRD) METHODS: We identified all individuals who had contributed at least 3 years of data to the GPRD and who had a diagnosis of SLE with supporting evidence of their diagnosis. We calculated the annual age- and sex-specific prevalence of SLE. Additionally, we stratified the prevalence by years of data contributed to the GRPD. RESULTS: In males the point estimate of the prevalence of SLE increased from 7.5/100,000 (CI(95) 6.3, 8.8) to 10.1/100,000 (CI(95) 7.8, 12.2) but this rise was not statistically significant. However, prevalence appeared to increase significantly amongst females from 42.6/100,000 (CI(95) 39.6, 45.6) in 1992 to 70.8/100,000 (CI(95) 65.1, 76.6) in 1998. This increase was mainly amongst women aged 50-79 and in those contributing more than 5 years of data and could not be explained by increasing incidence of SLE or decreasing mortality during the study period. CONCLUSIONS: We found an increasing prevalence of SLE that could not be explained by increasing incidence or decreasing mortality. This is almost certainly an artefact caused by the increased likelihood of detecting or confirming cases of chronic relapsing-remitting diseases with increasing time contributed to the GPRD.

Myocardial infarction risk and hormone replacement: differences between products.

OBJECTIVES: To establish the risk of myocardial infarction (MI) in users of hormone replacement therapy (HRT) compared with non-users and to compare the risk between different HRT regimens. METHODS: A population-based cohort and case-control study, and a case-control study nested within a cohort of HRT users, using the UK General Practice Research Database. Differences between HRT regimen, mode of administration and duration and recency of use were examined whilst adjusting for confounding. RESULTS: In the cohort and case-control study, 4537 cases of MI were identified in 2.62 million observed women years, cases were age-matched to 27,220 controls. In both studies, current and past HRT use were associated with reduced risk estimates for MI compared with no prior use. MIs were less likely to be fatal amongst women who had used HRT than amongst never users (OR(adj) 0.58; 95% CI 0.45-0.75). No difference in risk was seen between current and past use, oral and transdermal HRT or between different regimens (p>0.44). In the nested study, no difference was found in the association with MI risk between different oestrogen-progestogen combinations or between different combinations and tibolone. Unopposed oestrogen use was not associated with a decrease in risk compared with combined HRT. CONCLUSIONS: These results are consistent with previous observational studies in supporting the hypothesis that use of postmenopausal HRT is associated with a decrease in risk of acute myocardial infarction (AMI). Case fatality differed between HRT users and non-users, suggesting a protective effect of HRT. This study does not demonstrate a difference between regimens.

Venous thromboembolism associated with cyproterone acetate in combination with ethinyloestradiol (Dianette): observational studies using the UK General Practice Research Database.

PURPOSE: To derive risk estimates for venous thromboembolism (VTE) in women prescribed cyproterone acetate combined with ethinyloestradiol (CPA/EE), a drug licensed in the UK for the treatment of women with acne or hirsutism. CPA/EE provides a treatment option for women with polycystic ovary syndrome (PCOS). CPA/EE has been associated with an increased risk of VTE. METHODS: Using the General Practice Research Database, we conducted cohort and case-control analyses in all women aged 15-39 and then nested in a population of women of the same age with acne, hirsutism or PCOS. RESULTS: The incidence rate ratio (IRR) for VTE in women exposed to CPA/EE versus conventional combined oral contraceptives (COCs) was significantly raised (all women: 1.92; 95% CI: 1.22,2.88; nested: 2.51; 95% CI: 1.07,5.75). Using exposure to conventional COCs as the reference, the adjusted odds ratio (ORadj) for VTE associated with CPA/EE was 1.45 (95% CI: 0.80,2.64) in all women and 1.71 (95% CI: 0.31,9.49) in women with acne, hirsutism or PCOS. CONCLUSIONS: The risk of VTE associated with CPA/EE use does not differ significantly from that associated with the use of conventional COCs. These data are reassuring and together with knowledge of the risks associated with other treatments for acne, in particular, should influence prescribing practice.

Utilisation of hormone replacement therapy in the United Kingdom. A descriptive study using the general practice research database.

OBJECTIVE: To determine prevalence and patterns of hormone replacement therapy (HRT) utilisation in women in the UK. DESIGN: Prospective observational study. SETTING: UK general practice. POPULATION: Women from general practices throughout the UK. METHODS: The study period was 1 January 1992 to 31 December 1998. Age-specific prevalence was calculated for each year. Trends in prescribing patterns were described over time. A sub-cohort of 'new starters' on HRT was identified to establish patterns of use, including duration of use and switching of preparations. Characteristics of the sub-cohort were compared with a reference group of non-HRT users. MAIN OUTCOME MEASURES: Prevalence, prescribing patterns and differences in characteristics between HRT users and non-HRT users. RESULTS: Among women aged 45-64, prevalence of HRT use increased from 18.6% in 1992 to 27.7% in 1998. Secular trends were observed away from prescribing combined-sequential preparations and towards use of combined-continuous preparations. Among the prescriptions for combined HRT products, only 4.3% contained medroxyprogesterone acetate (MPA). A total of 45.7% of women without a record of a hysterectomy and 53.8% of women with a record of a hysterectomy used HRT for at least three years. When women were partitioned by year of starting HRT, there was a trend of increasing duration of use across the seven years. Some women without a record of a hysterectomy were receiving unopposed oestrogen without progestogen supplementation. CONCLUSIONS: Within the past decade, use of HRT has increased among women in the UK with large numbers of women using HRT for long periods and treatment often tailored to the individual.

Differences in the use of combined oral contraceptives amongst women with and without acne.

BACKGROUND: Cyproterone acetate combined with ethinyl estradiol (CPA/EE) provides a treatment option for women with acne, hirsutism or polycystic ovary syndrome (PCOS). CPA/EE may be prescribed as an oral contraceptive (OC), but is not licensed as such in the UK. The use of CPA/EE steadily increased after its introduction to the UK market in 1987, but there was a marked increase in its share of the OC market after 1995. METHODS: Using the General Practice Research Database, utilization patterns of CPA/EE and conventional oral contraceptives were compared in women aged 15-39 years, with or without acne or PCOS. RESULTS: Between 1994 and 1998, CPA/EE accounted for an increasing proportion of all OC use. The proportion of CPA/EE prescribed to women with acne declined between 1994 and 1998, whereas that prescribed to women with PCOS remained constant. The age-specific use of CPA/EE by women with acne or PCOS almost doubled. After 1995, there was a marked increase in the use of products containing levonorgestrel by women with acne or PCOS. CONCLUSIONS: A large proportion of CPA/EE is prescribed to women with acne and/or PCOS, although this proportion decreased between 1992 and 1998. This has important implications in CPA/EE risk assessment studies.

The risk of venous thromboembolism in women prescribed cyproterone acetate in combination with ethinyl estradiol: a nested cohort analysis and case-control study.

BACKGROUND: Cyproterone acetate combined with ethinyl estradiol (CPA/EE) is licensed in the UK for the treatment of women with acne and hirsutism and is also a treatment option for polycystic ovary syndrome (PCOS). Previous studies have demonstrated an increased risk of venous thromboembolism (VTE) associated with CPA/EE compared with conventional combined oral contraceptives (COCs). We believe the results of those studies may have been affected by residual confounding. METHODS: Using the General Practice Research Database we conducted a cohort analysis and case-control study nested within a population of women aged between 15 and 39 years with acne, hirsutism or PCOS to estimate the risk of VTE associated with CPA/EE. RESULTS: The age-adjusted incidence rate ratio for CPA/EE versus conventional COCs was 2.20 [95% confidence interval (CI) 1.35-3.58]. Using as the reference group women who were not using oral contraception, had no recent pregnancy or menopausal symptoms, the case-control analysis gave an adjusted odds ratio (OR(adj)) of 7.44 (95% CI 3.67-15.08) for CPA/EE use compared with an OR(adj) of 2.58 (95% CI 1.60-4.18) for use of conventional COCs. CONCLUSIONS: We have demonstrated an increased risk of VTE associated with the use of CPA/EE in women with acne, hirsutism or PCOS although residual confounding by indication cannot be excluded.

Incidence and prevalence of lower urinary tract symptoms suggestive of benign prostatic hyperplasia in primary care--the Triumph project.

OBJECTIVE: Benign prostatic hyperplasia (BPH) is one of the most common conditions associated with ageing in men. BPH often presents as lower urinary tract symptoms (LUTS) due to difficulties in voiding and irritability of the bladder. We conducted a retrospective cohort study within the Integrated Primary Care Information (IPCI) database, a general practitioners database in The Netherlands, to assess the incidence of LUTS suggestive of BPH (LUTS/BPH) in the general population. MATERIALS: Our study population comprised all males, 45 years or older who were registered for at least 6 months prior to start of follow-up. The study period lasted from 1 January 1995 to 31 December 2000. Cases of LUTS/BPH were defined as persons with a diagnosis of BPH, treatment or surgery for BPH, or urinary symptoms suggestive of BPH that could not be explained by other co-morbidity. RESULTS: The study cohort comprised 80,774 males who contributed 141,035 person-years of follow-up. We identified 2181 incident and 5605 prevalent LUTS/BPH cases. The overall incidence rate of LUTS/BPH was 15 per 1000 man-years (95% CI: 14.8-16.1). The incidence increased linearly (r(2) = 0.99) with age from three cases per 1000 man-years at the age of 45-49 years (95% CI: 2.4-3.6) to a maximum of 38 cases per 1000 man-years at the age of 75-79 years (95% CI: 34.1-42.9). After the age of 80 years, the incidence rate remained constant. For a symptom-free man of 46 years, the risk to develop LUTS/BPH over the coming 30 years, if he survives, is 45%. The overall prevalence of LUTS/BPH was 10.3% (95% CI: 10.2-10.5). The prevalence rate was lowest among males 45-49 years of age (2.7%) and increased with age until a maximum at the age of 80 years (24%). CONCLUSIONS: The incidence rate of LUTS/BPH increases linearly with age and reaches its maximum at the age of 79 years.

Study of the association between ischemic heart disease and use of alpha-blockers and finasteride indicated for the treatment of benign prostatic hyperplasia.

OBJECTIVE: Given the high possibility of co-occurrence of benign prostatic hyperplasia (BPH) and cardiovascular disease, we evaluated whether patients using BPH drugs are at an increased risk of acute hospital admission for ischemic heart disease (IHD). METHODS: A nested case control study within a cohort of 4414 men (aged > or =30 years) who had a history of using BPH products between 1992 and 1998 was conducted. Cases were defined as men with a first record of an acute hospital admission for IHD during the study period; three controls were matched to each case on year of birth, pharmacy and calendar time (index date). RESULTS: The study population comprised 220 cases and 515 controls. Current use of alpha-blockers (adjusted odds ratio 1.0, 95% confidence interval: 0.5-2.2) or finasteride (adjusted odds ratio 0.3, 95% CI: 0.1-1.4) was not associated with hospital admission for IHD. Furthermore, current use of BPH drugs was not associated with IHD in patient subgroups (age, history of cardiovascular disease, diabetes), nor with duration of use prior to hospitalization. CONCLUSION: Although the power of the study was low, we found no evidence for an association between current use of BPH drugs and hospital admission for IHD. Therefore, our study seems to confirm the good cardiovascular safety profile of modern BPH drugs.