Scientific
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BACKGROUND: Idiopathic pulmonary fibrosis (IPF) and sarcoidosis are common diagnoses in patients attending chest clinics, but little is known about the epidemiology of these diseases. We used data from a general practice database to provide information on the current incidence of IPF and sarcoidosis in the UK. METHODS: Data were extracted for all patients with a diagnosis of IPF or sarcoidosis between 1991 and 2003. The whole population of the database was used to calculate disease incidence stratified by age, sex, region, and time period. Poisson regression was used to compare the incidence between populations and Cox regression was used to compare survival between populations. RESULTS: 920 cases of IPF (mean age 71 years, 62% male) and 1019 cases of sarcoidosis (mean age 47 years, 47% male) were identified. The overall incidence rate per 100 000 person-years was 4.6 for IPF and 5.0 for sarcoidosis. The incidence of IPF increased progressively between 1991 and 2003 (p<0.00001), and was highest in Northern England and Scotland (p<0.0001). The survival of patients with IPF was stable over time. In contrast, the incidence of sarcoidosis was highest in London, West Midlands and Northern Ireland and remained stable over time. CONCLUSIONS: The incidence of IPF has more than doubled between 1990 and 2003; this is not due to the ageing of the UK population or an increased ascertainment of milder cases. The incidence of sarcoidosis has not changed during this time period. Our findings suggest that more than 4000 new cases of IPF and 3000 new cases of sarcoidosis are currently diagnosed each year in the UK.

BACKGROUND: Simple tools are needed to identify patients at high risk of fracture. AIM: To develop a simple clinical tool for assessing 5-year risk of fracture. DESIGN: Cohort study. METHODS: The study population consisted of all women aged 50+ included in the THIN Research Database (containing computerized medical records of UK general practices). Using Cox proportional hazards models, a risk score was initially estimated from age, body mass index, and clinical risk factors. The 5-year risk of fracture (survival function) was estimated for each score. RESULTS: The study population included 366 104 women aged > or = 50 years (mean follow-up 5.8 years). Of these, 6453 suffered a hip fracture. Several characteristics independently contributed to the fracture risk score (age, body mass index, fracture and fall history, previous diagnoses and use of medication). The 5-year risks for hip fracture for patients with total scores of 10, 30 and 50 were 0.3% (95%CI 0.3-0.4%), 2.2% (95%CI 2.1-2.2%), and 13.1% (95%CI 12.5-13.7%), respectively. A woman aged 65 years with low BMI and a history of both fracture and falling would have a hip fracture risk score of 37, with a corresponding 5-year risk for a hip fracture of 4.1% (4.0-4.2%). The risk score was validated and tested in another population (from GPRD), with a good concurrence between predicted and observed risks of fracture. DISCUSSION: This risk score predicts the long-term risk of fracture, and could be used for targeting patients for further investigation, such as bone densitometry.

BACKGROUND: Adrenal insufficiency, a well recognised complication of treatment with oral corticosteroids, has been described in association with inhaled corticosteroid use in over 60 case reports. The risk of adrenal insufficiency in people prescribed an oral or inhaled corticosteroid in the general population is not known. A study was undertaken to quantify the association between adrenal insufficiency and oral and inhaled corticosteroid exposure. METHODS: A case-control study was performed using computerised general practice data from The Health Improvement Network. RESULTS: From a cohort of 2.4 million people, 154 cases of adrenal insufficiency and 870 controls were identified. There was a dose related increased risk of adrenal insufficiency in people prescribed an oral corticosteroid with an odds ratio of 2.0 (95% CI 1.6 to 2.5) per course of treatment per year. Adrenal insufficiency was associated with a prescription for an inhaled corticosteroid during the 90 day period before the diagnosis with an odds ratio of 3.4 (95% CI 1.9 to 5.9) and this effect was dose related (p for trend <0.001). After adjusting for oral corticosteroid exposure, this odds ratio was reduced to 1.6 (95% CI 0.8 to 3.2) although the dose relation remained (p for trend 0.036). CONCLUSION: People prescribed an oral or inhaled corticosteroid are at a dose related increased risk of adrenal insufficiency although the absolute risk is small. This analysis suggests that the increased risk in people prescribed an inhaled corticosteroid is largely due to oral corticosteroid exposure, but inhaled corticosteroids may have an effect when they are taken at higher doses.

BACKGROUND: Acute infection increases the risk of arterial cardiovascular events, but effects on venous thromboembolic disease are less well established. Our aim was to investigate whether acute infections transiently increase the risk of venous thromboembolism. METHODS: We used the self-controlled case-series method to study the risk of first deep vein thrombosis (DVT) (n=7278) and first pulmonary embolism (PE) (n=3755) after acute respiratory and urinary tract infections. Data were obtained from records from general practices who had registered patients with the UK's Health Improvement Network database between 1987 and 2004. FINDINGS: The risks of DVT and PE were significantly raised, and were highest in the first two weeks, after urinary tract infection. The incidence ratio for DVT was 2.10 (95% CI 1.56-2.82), and that for PE 2.11 (1.38-3.23). The risk gradually fell over the subsequent months, returning to the baseline value after 1 year. The risk of DVT was also higher after respiratory tract infection, but possible diagnostic misclassification precluded a reliable estimate of the risk of PE after respiratory infection. INTERPRETATION: Acute infections are associated with a transient increased risk of venous thromboembolic events in a community setting. Our results confirm that infection should be added to the list of precipitants for venous thromboembolism, and suggest a causal relation.

OBJECTIVE: To determine whether nicotine replacement therapy (NRT) is associated with an increased risk of acute myocardial infarction, acute stroke, or death. DESIGN: Self control case series analysis of data from The Health Improvement Network (THIN) to estimate the relative incidence of myocardial infarction and stroke in four 14 day periods before and after the first prescription for NRT. SETTING: THIN is a computerised general practice database. SUBJECTS: Patients contributing data to THIN. INTERVENTIONS: Observational study of NRT. MAIN OUTCOMES: Acute myocardial infarction, acute stroke, and death. RESULTS: 33,247 individuals had been prescribed NRT, of whom 861 had had a myocardial infarction and 506 a stroke. There was a progressive increase in the incidence of first myocardial infarction in the 56 days leading up to the first NRT prescription (overall incidence ratio 5.55, 95% confidence interval (CI) 4.42 to 6.98), but the incidence fell after this time and was not increased in the 56 days after starting NRT (incidence ratio 1.27, 95% CI 0.82 to 1.97). The results were similar for second myocardial infarction and stroke, and for subgroups of people with pre-existing angina and hypertension. There were 960 deaths in our cohort during a mean follow up period of 2.6 years after starting NRT, with no evidence of an increased mortality in the 56 days after the NRT prescription (incidence ratio 0.86, 95% CI 0.60 to 1.23). CONCLUSIONS: The use of NRT is not associated with any increase in the risk of myocardial infarction, stroke, or death.

BACKGROUND: Bupropion is an effective smoking cessation therapy but its use in the UK has been limited by concerns that it may increase the risk of sudden death. METHODS: Data for all patients prescribed bupropion within The Health Improvement Network (a computerised general practice database) were extracted and the self-controlled case-series method was used to estimate the relative incidence of death during the first 28 days of treatment. The incidence of seizures, a recognised adverse effect of bupropion, was also investigated during this period. RESULTS: A total of 9329 individuals had been prescribed bupropion (mean age 44 years, 48% male). The total person-time after the first prescription for bupropion was 17,586 years, and during this time 121 people died. Two people died within the first 28 days of treatment, which was less than expected in comparison with the remaining observation period by an incidence ratio of 0.50 (95% confidence interval (CI) 0.12 to 2.05). Twenty eight people were recorded as having a total of 45 seizures (23 before starting bupropion, two in the first 28 days of treatment, and 20 at a later point). The relative incidence of seizures during the first 28 days of treatment was 3.62 (95% CI 0.87 to 15.09), equivalent to one additional seizure per 6219 first time bupropion users. CONCLUSIONS: Bupropion use is probably associated with an increased risk of seizures, but no evidence was found to suggest that the drug is associated with an increased risk of sudden death.

BACKGROUND: A 15-fold increased risk of gastrointestinal bleeding has been reported with concurrent use of selective serotonin reuptake inhibitors and non-steroidal anti-inflammatory drugs. Recent guidance cautions against concurrent prescription, particularly in older people. AIM: To quantify the risk of gastrointestinal bleeding associated with current exposure to non-steroidal anti-inflammatory drugs, selective serotonin reuptake inhibitors, and both drugs concurrently. METHODS: We conducted a case-control analysis of 11,261 cases with upper gastrointestinal bleeding and 53,156 controls matched by gender, age and general practice from computerized primary care data. We coupled this with self-controlled case series analysis. RESULTS: Both drugs were associated with a twofold increased risk of gastrointestinal bleeding (odds ratio =2.38, 95% confidence interval 2.08-2.72 for selective serotonin reuptake inhibitors and odds ratio = 2.15, 95% confidence interval 2.02-2.28 for non-steroidal anti-inflammatory drugs). This increased risk was marginally higher for concurrent prescription (odds ratio = 2.93, 95% confidence interval 2.25-3.82). The self-controlled analysis showed a greater incidence rate ratio for gastrointestinal bleeding with non-steroidal anti-inflammatory drugs (2.71, 95% confidence interval 2.51-2.91) and lower incidence rate ratio with selective serotonin reuptake inhibitors (1.71, 95% confidence interval 1.48-1.98). The incidence rate ratio when both drugs were combined was 3.25, 95% confidence interval 1.95-5.42. Estimates were similar after restricting to people over 80 years of age. Increased risk of gastrointestinal bleeding was not specifically related to class of non-steroidal anti-inflammatory drugs and was similar when we looked at tricyclic anti-depressants. CONCLUSIONS: Our study suggests that the risk of gastrointestinal bleeding is not substantially increased when non-steroidal anti-inflammatory drugs and selective serotonin reuptake inhibitors are prescribed together, compared with their use alone.