Statins and Colorectal Cancer Risk: A Population-Based Case-Control Study and Synthesis of the Epidemiological Evidence.

(1) Background: The pleiotropic effects of statins may explain a chemoprotective action against colorectal cancer (CRC). Many studies have tested this hypothesis, but results have been inconsistent so far. Moreover, few have examined statins individually which is important for determining whether there is a class effect and if lipophilicity and intensity may play a role. (2) Methods: From 2001-2014, we carried out a study comprised of 15,491 incident CRC cases and 60,000 matched controls extracted from the primary healthcare database BIFAP. We fit a logistic regression model to compute the adjusted-odds ratios (AOR) with their 95% confidence intervals (CIs). Additionally, we carried out a systematic review and meta-analysis. (3) Results: Current use of statins showed a reduced risk of CRC (AOR = 0.87; 95% CI: 0.83-0.91) not sustained after discontinuation. The association was time-dependent, starting early (AOR6months-1year = 0.85; 95% CI: 0.76-0.96) but weakened beyond 3-years. A class effect was suggested, although only significant for simvastatin and rosuvastatin. The risk reduction was more marked among individuals aged 70 or younger, and among moderate-high intensity users. Forty-eight studies were included in the meta-analysis (pooled-effect-size = 0.90; 95% CI: 0.86-0.93). (4) Conclusions: Results from the case-control study and the pooled evidence support a moderate chemoprotective effect of statins on CRC risk, modified by duration, intensity, and age.

Renal decline in patients with non-valvular atrial fibrillation treated with rivaroxaban or warfarin: A population-based study from the United Kingdom.

BACKGROUND: Reports suggest that renal decline is greater among patients with non-valvular atrial fibrillation (NVAF) treated chronically with warfarin vs. some non-vitamin K antagonist oral anticoagulants. METHODS AND RESULTS: Using primary care electronic health records from the United Kingdom we followed adults with NVAF and who started rivaroxaban (20 mg/day, N = 5338) or warfarin (N = 6314), excluding those with estimated glomerular filtration rate (eGFR) <50 ml/min/1.73m2, end-stage renal disease (ESRD) or no eGFR or serum creatinine (SCr) values recorded in the previous year. Outcomes were: doubling SCr levels, ≥30% decline in eGFR and progression to ESRD. We calculated adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) for each outcome. Average eGFR slope was estimated using mixed model regression. After a mean follow-up 2.5 years, the number of incident cases of adverse renal events within the two cohorts was: doubling SCr (n = 322), ≥30% decline in eGFR (n = 1179), and progression to ESRD (n = 22). Adjusted HRs (95% CIs) for the renal outcomes among rivaroxaban vs. warfarin users were: doubling SCr, 0.63 (0.49-0.81); ≥30% decline in eGFR, 0.76 (0.67-0.86); ESRD, 0.77 (0.29-2.04). Similar results were observed among patients with diabetes or heart failure. Estimated mean decline in renal function over the study period was 2.03 ml/min/1.73 m2/year among warfarin users and 1.65 ml/min/1.73 m2/year among rivaroxaban users (p = 0.03). CONCLUSIONS: We found clear evidence that patients with NVAF, preserved renal function at baseline and treated with rivaroxaban had a markedly reduced risk and rate of renal decline compared with those treated with warfarin.

Low-dose aspirin and risk of gastric and oesophageal cancer: A population-based study in the United Kingdom using The Health Improvement Network.

There is increasing interest regarding potential protective effects of low-dose aspirin against various gastrointestinal cancers. We aimed to quantify the association between use of low-dose aspirin and risk of gastric/oesophageal cancer using a population-based primary care database in the UK. Between January 2005 and December 2015, we identified a cohort of 223 640 new users of low-dose aspirin (75-300 mg/day) and a matched cohort of nonusers at the start of follow-up from The Health Improvement Network. Cohorts were followed to identify incident cases of gastric/oesophageal cancer. Nested case-control analyses were conducted and adjusted odds ratios (ORs) with 95% confidence intervals (CIs) were calculated for current vs nonuse of low-dose aspirin using logistic regression. Current use was defined as when low-dose aspirin lasted 0 to 90 days before the index date (event date for cases, random date for controls) and previous duration was ≥1 year. We identified 727 incident cases of gastric cancer and 1394 incident cases of oesophageal cancer. ORs (95% CIs) were 0.46 (0.38-0.57) for gastric cancer and 0.59 (0.51-0.69) for oesophageal cancer. The effect remained consistent with no clear change seen between previous duration of low-dose aspirin use of 1-3, 3-5 or >5 years. The reduced risks was seen with 75 mg/day, and effects were consistent in lag-time analyses. In conclusion, our results indicate that use of low-dose aspirin is associated with a 54% reduced risk of gastric cancer and a 41% reduced risk of oesophageal cancer as supported by mechanistic data.

No association between use of phosphodiesterase 5 inhibitors and colorectal cancer in men with erectile dysfunction.

PURPOSE: There is an increase interest on the potential chemoprotective effect of selective phosphodiesterase 5 (PDE5) inhibitors. Several authors have shown in vivo the immune-mediated anti-tumor effect of these inhibitors on tumors arising from the digestive tract. OBJECTIVES: To test the potential effect of selective PDE5 inhibitors against colorectal cancer (CRC) onset previously observed. METHODS: We used data from The Health Improvement Network database and identified an established cohort of 200 000 new users of low-dose aspirin and a matched comparison cohort aged 40-84 years between 1 January 2000 and 31 December 2011. A follow-up to identify CRC cases was performed within an extensive validation exercise. Nested case-control analyses compared PDE5 inhibitors vs non-use on CRC risk were performed. RESULTS: Restricting to males (59.3% controls and 59.5% cases), no association was observed among current users of PDE5 inhibitors (1.05 [95% CI: 0.69-1.60]) and neither among recent (1.36 [95% CI: 0.81-2.28]) or past users (1.06 [95% CI: 0.72-1.58]). No duration response effect was found. CONCLUSIONS: Our results do not support an increased risk of CRC associated with the use of PDE5 inhibitors among men with erectile dysfunction.

Impact of chronic kidney disease definition on assessment of its incidence and risk factors in patients with newly diagnosed type 1 and type 2 diabetes in the UK: A cohort study using primary care data from the United Kingdom.

AIM: To estimate the incidence and risk factors of chronic kidney disease (CKD) in patients with newly-diagnosed diabetes using different CKD definitions. METHODS: Using UK primary care data, patients with diabetes (type 1, 4691; type 2, 109,365) and no CKD were followed to identify newly-diagnosed CKD, classified by a broad and narrow CKD definition (to capture diabetes-induced CKD, termed diabetic kidney disease, DKD). Adjusted incidence rates of CKD/DKD were calculated, and risk factors identified using Cox regression. RESULTS: There were 404 CKD cases and 147 DKD cases among patients with type 1 diabetes (T1D), and 29,104 CKD cases, 9284 DKD cases among patients with type 2 diabetes (T2D). Adjusted incidence rates of CKD per 100 years were 5.4 (T1D) and 5.5 (T2D); for DKD they were 1.9 and 1.5, respectively. Risk factors for CKD/DKD were older age, high social deprivation, obesity, cardiovascular disease, hypertension and smoking. Poor glycaemic control in the year after diabetes diagnosis was a strong predictor of CKD/DKD occurrence beyond this first year, and a risk factor for CKD/DKD in T2D. CONCLUSIONS: CKD and DKD remain common in diabetics in the decade after diagnosis. Early prevention of T2D and aggressive treatment of risk factors is urgent.

The effect of low-dose aspirin on colorectal cancer prevention and gastrointestinal bleeding according to bodyweight and body mass index: Analysis of UK primary care data.

BACKGROUND: Meta-analysis of trial data suggests that in primary cardiovascular disease (CVD) prevention bodyweight modifies low-dose aspirin's effects on colorectal cancer (CRC) and major bleeding risk. We sought to investigate whether these effects are seen in patients with or without CVD in routine clinical practice by undertaking sub-analyses of data from two cohort studies with nested-case-control analyses. METHODS: We followed ~200,000 new users of low-dose aspirin (75-300 mg/day) and a matched cohort of non-users to identify incident cases of CRC/upper gastrointestinal bleeding (UGIB). Adjusted relative risks (RRs) with 95% confidence intervals (CIs) were calculated for current vs. non-use of low-dose aspirin using logistic regression stratified by bodyweight/body mass index (BMI) strata. RESULTS: RRs (95% CIs) for CRC by bodyweight were: 0.60 (0.50-0.72) for ≤70 kg, 0.68 (0.60-0.76) for >70 kg; and by BMI were 0.60 (0.52-0.68) for ≤28 kg/m2, 0.76 (0.64-0.89) for >28 kg/m2. For UGIB, estimates were: 1.49 (1.28-1.74) for ≤90 kg, 1.78 (1.29-2.45) for >90 kg/m2, 1.44 (1.21-1.72) for ≤28 kg/m2, 1.72 (1.38-2.16) for >28 kg/m2. Results were similar in the primary CVD prevention population. CONCLUSION: Our findings suggest that the effects of low-dose aspirin in reducing CRC risk and increasing UGIB risk are not modified by bodyweight/BMI.

Population-based case-control study: chemoprotection of colorectal cancer with non-aspirin nonsteroidal anti-inflammatory drugs and other drugs for pain control.

BACKGROUND: Inflammation and overexpression of cyclooxygenase-2 (COX-2) have been described to play a key role in the progression from nonpathologic intestinal mucosa to colorectal cancer (CRC). AIMS: To assess the chemoprotective effect of non-aspirin nonsteroidal anti-inflammatory drugs (NA-NSAIDs) under different patterns of use in a Mediterranean population and to explore the potential effect of symptomatic slow-acting drugs for osteoarthritis (SYSADOAs; chondroitin sulfate and glucosamine) and metamizole (or dipyrone), also reported to influence COX-2 activity. METHODS: We performed a case-control study nested in a cohort extracted from the primary care database, BIFAP. From 2001 to 2014, we included 15 491 incident cases and 60 000 random controls. To estimate the association between the drugs of interest and CRC, we built logistic regression models to compute the adjusted-odds ratios (AOR) and 95% confidence intervals (CI). RESULTS: NA-NSAIDs use was associated with a reduced risk of CRC (AOR = 0.67; 95% CI: 0.63-0.71) and increased linearly with duration of treatment (p for trend <0.001). The effect diminished upon discontinuation but persisted statistically significant up to 1 year. All individual NA-NSAIDs examined showed a decreased risk. The concomitant use of proton-pump inhibitors (PPI) had no impact on the protective effect of NA-NSAIDs; AORPPI + NSAID  = 0.64; 0.58-0.71. SYSADOA use was associated with a reduced risk (0.79; 0.69-0.90) but disappeared after the exclusion of NSAID users during the previous 1 or 3 years (0.85; 0.70-1.04 and 1.00; 0.76-1.31 respectively). Metamizole did not show a chemoprotective effect. CONCLUSIONS: NA-NSAID use is associated with a duration-dependent risk reduction of CRC not shared by SYSADOAs or metamizole.

Predictors of Over-Anticoagulation in Warfarin Users in the UK General Population: A Nested Case-Control Study in a Primary Health Care Database.

BACKGROUND: Many patients on warfarin therapy often present with supratherapeutic international normalized ratio (INR) levels, resulting from the influence of several patient-specific factors, which have been associated with adverse outcomes. OBJECTIVE: This article aims to identify risk factors for over-anticoagulation (INR levels ≥4) in a cohort of patients taking warfarin. METHODS: A cohort of warfarin users aged 18 to 85 years from January 2005 to April 2013 was identified in The Health Improvement Network U.K. primary care database (N = 12,506). A random date was assigned to all patients within their eligible person-time (index date), and a nested case-control analysis was performed with individuals presenting a first episode of INR level ≥4 after the index date used as cases (N = 699) and patients with non-supratherapeutic INR values (≤3) as controls (N = 9,798). Using unconditional logistic regression models, odds ratios with 95% confidence intervals were calculated adjusted for potential confounders. Two sensitivity analyses were performed with alternative definitions of over-anticoagulation (INR levels ≥5 or > 3). RESULTS: Among the factors examined, the strongest predictors of over-anticoagulation were warfarin indication (in particular, valvular atrial fibrillation and valve replacement), renal failure (with the risk increasing steeply with decreasing estimated glomerular filtration rate), cancer, anaemia, respiratory infections treated with antibiotics, chronic obstructive pulmonary disease treated with ß2-agonists, polypharmacy (≥10 medications), low socio-economic status and residency in rural areas. Similar results were obtained when supratherapeutic levels were defined as INR ≥5 or, alternatively, as INR > 3. CONCLUSION: Predictors of supratherapeutic INR levels found in this study might help physicians identify patients where closer INR monitoring is warranted.

Feasibility and validity of The Health Improvement Network database of primary care electronic health records to identify and characterise patients with small cell lung cancer in the United Kingdom.

BACKGROUND: Epidemiological research on small cell lung cancer (SCLC) is limited and based on cancer registry data. We evaluated the feasibility and validity of using primary care electronic health records (The Health Improvement Network [THIN]) in the UK to identify and characterise SCLC. METHODS: We searched THIN records of individuals aged 18-89 years between 2000 and 2014 for a first diagnostic code suggestive of lung cancer (group 1) or small cell cancer (SCC; group 2) and for text strings among free text comments to identify and characterise incident SCLC cases. We validated our case identification strategy by manual review of patient EHRs, including free text comments, for a random sample of 400 individuals initially detected with a diagnostic code (300 from group 1 and 100 from group 2). RESULTS: Twenty five thousand two hundred fourty one individuals had a code for lung cancer (n = 24,508 [97.1%]) or SCC (733 [2.9%]). Following free-text searches, there were 3530 incident SCLC cases (2956 from group 1; 574 from group 2) corresponding to an incidence rate of 1.01 per 10,000 person-years. In the validation exercise, SCLC confirmation rates were 99% (group 1) and 85% (group 2). Mean age at diagnosis among confirmed cases was 68.5 years; staging information was present in 63.5% of cases of whom 17.8% had limited disease and 82.2% had extensive disease. The majority (84.5%) had a recorded symptom suggestive of lung cancer; chest infection was the most common (18%) followed by cough (15.8%) and chest/abdominal/back pain (15.2%). The first year crude mortality rates was 9.9 per 100 person-months (95% confidence interval [CI] 9.5-10.4), was higher among men and those aged 80 years and above. A total of 144 (37.8%) confirmed cases had metastases recorded. Median survival among the whole study cohort was 7.37 months. CONCLUSIONS: Our SCLC case identification method appears to be valid and could potentially be adapted to identify other cancer types. However, complete characterisation of staging requires information from additional data sources including cancer registries.

Incidence of Upper and Lower Gastrointestinal Bleeding in New Users of Low-Dose Aspirin.

BACKGROUND & AIMS: There are few data on the incidence of upper and lower gastrointestinal bleeding (UGIB and LGIB) from observational studies of low-dose aspirin users. We aimed to estimate incidence rates of UGIB and LGIB in a large cohort of new users of low-dose aspirin in the United Kingdom, with subanalyses of hospitalization status and fatalities. METHODS: We performed a population-based study of 199,079 new users of low-dose aspirin (median age, 64.0 years) identified from the Health Improvement Network primary care database (2000-2012). Individuals were followed for a median 5.4 years (maximum, 14 years) to identify new cases of UGIB and LGIB. Following multistep validation, we calculated overall and age- and sex-specific incidence rates; we performed subanalyses for health care use and death within 30 days of GIB. We also estimated rates within a matched (1:1) cohort of nonusers of low-dose aspirin at the start of the follow-up period. RESULTS: The low-dose aspirin users had 1115 UGIB events and 1936 LGIB events; most subjects with UGIB events (58.9%) were hospitalized, whereas most subjects with LGIB events were referred to secondary care (72.8%). Crude incidence rates of GIB per 1000 person-years were 0.97 for subjects with UGIB (95% CI, 0.91-1.02) and 1.68 for subjects with LGIB (95% CI, 1.60-1.75). Incidence rates per 1000 person-years for patients hospitalized for GIB were 0.57 for UGIB (95% CI, 0.53-0.61) and 0.45 for LGIB (95% CI, 0.42-0.49); for referred (but not hospitalized) cases, these values were 0.39 for UGIB (95% CI, 0.36-0.43) and 1.22 for LGIB (1.16-1.29). Incidence rates per 1000 person-years were 0.06 for fatal UGIB (95% CI, 0.04-0.07), 0.01 for fatal LGIB (95% CI, 0.01-0.02), 0.91 for nonfatal UGIB (95% CI, 0.86-0.97), and 1.66 for nonfatal LGIB (95% CI, 1.59-1.74). Among nonusers of low-dose aspirin, incidence rates per 1000 person-years were 0.67 (95% CI, 0.63-0.75) for UGIB and 0.76 (95% CI, 0.72-0.82) for LGIB. CONCLUSION: In a population-based study of low-dose aspirin users, the incidence of LGIB was higher than the incidence of UGIB. However, incidence rates of hospitalized GI bleeds and 30-day mortality rates were lower for LGIB than for UGIB. These estimates are valuable for benefit-risk assessments of low-dose aspirin for cardiovascular and colorectal cancer prevention.

Clopidogrel and Low-Dose Aspirin, Alone or Together, Reduce Risk of Colorectal Cancer.

BACKGROUND & AIMS: The antiplatelet effect of low-dose aspirin, via inhibition of cyclooxygenase-1, might contribute to its ability to reduce the risk of colorectal cancer (CRC). Antiplatelet agents with a different mechanism, such as clopidogrel, might have the same effects. We aimed to quantify the effects of low-dose aspirin and clopidogrel on the risk of CRC in a Mediterranean population. METHODS: We performed a nested case-control study using a primary care database (Base de datos para la Investigación Farmacoepidemiológica en Atención Primaria) in Spain. We collected data, from 2001 through 2014, on 15,491 incident cases of CRC and 60,000 randomly selected individuals (controls), frequency-matched to cases by age, sex, and year. To estimate the association between exposure to different antiplatelet agents and the risk of colorectal cancer, we built multiple logistic regression models and computed the adjusted-odds ratios (AORs) and their respective 95% CIs. RESULTS: Use of low-dose aspirin was associated with a reduced risk of CRC overall (AOR, 0.83; 95% CI, 0.78-0.89) and in patients receiving treatment for more than 1 year (AOR, 0.79; 95% CI, 0.73-0.85). Use of clopidogrel was associated with a decreased risk of CRC overall (AOR, 0.8; 95% CI, 0.69-0.93) and in patients receiving treatment for more than 1 year (AOR, 0.65; 95% CI, 0.55-0.78). Dual antiplatelet therapy had the same effect as either drug taken as monotherapy. No modification by sex or age was observed. CONCLUSIONS: In a nested case-control study of a primary care database in Spain, we found clopidogrel use, alone or in combination with low-dose aspirin, to reduce the risk of CRC by 20% to 30%, a magnitude similar to that of low-dose aspirin alone. These data support the concept that inhibiting platelets is an effective strategy for prevention of CRC.

Validation study of colorectal cancer diagnosis in the Spanish primary care database, BIFAP.

PURPOSE: To define and validate a case-finding algorithm to identify incident colorectal cancer (CRC) in the Spanish primary care database BIFAP. METHODS: All potential incident CRC cases recorded during the study period 2001 to 2014 among patients 20 to 89 years old were identified using a defined case-finding algorithm tailored to BIFAP database characteristics and based on codes plus text mining strategies. Potential CRC cases identified by the algorithm were classified into eight homogeneous groups according to recording characteristics. Random samples of 100 cases per group were obtained, and electronic medical records were manually reviewed by two independent researchers. Positive predictive values (PPVs) were estimated per each group and for the whole sample taking into account the stratified sampling. Standardized incidence rate (SIR) of CRC was estimated and compared with that reported by the National Cancer Registry. Negative predictive value (NPV) was also estimated in a random sample of 100 non-CRC patients by the algorithm. RESULTS: A total of 17 008 potential CRC cases were identified. Most of them (14793; 87%) were recorded as incident diagnosis with linked clinical notes as free text, having this group a PPV of 92.1% (95%CI: 87.1%-95.3%). The overall PPV including all groups was 87.3% (95%CI: 83.3%-90.4%). SIR of CRC was 55.5 per 100.000 person-years. SIR increased with age and was higher in men as compared with women (77.7 vs 38.1 per 100.000 py, respectively) which were in line with those reported by the Network of Cancer Registries in Spain. NPV was of 100% (96.3%-100%). CONCLUSIONS: This study shows a high validity of the CRC cases identified by the algorithm and a high level of CRC recording in BIFAP database and supports its appropriateness to validly identify incident CRC cases in BIFAP.

Predictors of Bleeding in Patients with Symptomatic Peripheral Artery Disease: A Cohort Study Using The Health Improvement Network in the United Kingdom.

The purpose of this analysis was to assess potential predictors of intra-cranial bleeding (ICB) and gastrointestinal bleeding (GIB) in patients with symptomatic peripheral artery disease (PAD) in UK primary care. Patients with symptomatic PAD diagnosed from 2000 to 2010 were identified from The Health Improvement Network (THIN; N = 28,484). A nested case-control analysis, adjusted for potential confounders, was performed to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for potential predictors of ICB or GIB. For GIB, follow-up was restricted to Hospital Episode Statistics-linked THIN practices. Median follow-up was 6 years. For ICB (153 cases), the OR (95% CI) was 3.85 (1.33-11.13) for previous ICB, 0.90 (0.61-1.34) for treated hypertension, 1.59 (0.65-3.87) for untreated hypertension and 1.38 (0.80-2.36) for current smoking. ORs for ICB were 0.78 (0.50-1.21), 0.40 (0.09-1.82) and 1.27 (0.47-3.47) with use of acetylsalicylic acid (ASA), clopidogrel and warfarin monotherapy, respectively, compared with non-use of such therapy. For GIB (506 cases), the OR was 1.40 (1.05-1.86) for peptic ulcer disease, 3.20 (1.81-5.64) for dual anti-platelet therapy use, 1.96 (1.46-2.64) for non-steroidal anti-inflammatory drug (NSAID) use and 1.01 (0.80-1.28) for proton pump inhibitor use. ORs for GIB were 1.78 (1.39-2.30), 2.03 (1.05-3.93) and 1.25 (0.72-2.16) with ASA, clopidogrel and warfarin monotherapy, respectively, compared with non-use. Previous ICB was a risk factor for ICB. Use of anti-platelet therapy or NSAIDs increased GIB risk. Identifying bleeding predictors could help optimize treatment strategies for patients with PAD.

Trends in the contemporary incidence of colorectal cancer and patient characteristics in the United Kingdom: a population-based cohort study using The Health Improvement Network.

BACKGROUND: Cancer registry data show that survival of colorectal cancer (CRC) in the United Kingdom is poor compared with other European countries and the United States, yet these data sources lack information on patient comorbidities and medication use, which could help explain these differences. METHODS: Among individuals aged 40-89 years in The Health Improvement Network (2000-2014), we identified first ever cases of CRC and calculated incidence rates with 95% confidence intervals (CIs). For CRC cases and non-cases in two separate calendar years (2002 and 2014), we evaluated patient demographics, lifestyle factors, comorbidities and medication use and bowel screening. RESULTS: The incidence of CRC remained relatively constant across the study period; incidence rates per 10,000 person-years (95% CIs) were 9.27 (8.59-1.01) in 2000, 10.65 (10.15-11.18) in 2007 and 8.37 (7.93-8.83) in 2014. Incidence rates per 10,000 person-years were higher in men than women at 11.44 (95% CI: 10.35-12.66) vs. 7.40 (95% CI: 6.59-8.32) in 2000, and 9.39 (95% CI: 8.74-10.10) vs. 7.38 (95% CI: 6.81-8.00) in 2014. An increase was seen in the proportion of CRC cases diagnosed at age < 60 years. In 2002, 3.5% of CRC cases were diagnosed at age 40-49 compared with 5.1% in 2014 (p = 0.064). Similarly, in 2002, 12.5% were diagnosed at age 50-59 years compared with 16.2% in 2014 (p = 0.002). Between 2002 and 2014, previous bowel screening increased in both CRC cases (+ 10.6%) and non-cases (+ 9.7%)(p < 0.001 for both groups). Greater rises in the following were seen among CRC cases compared with non-cases: diabetes (+ 9.3% vs. + 3.3%; p < 0.001 for both), obesity (+ 14.5% vs. + 10.1%; p < 0.001 for both), hypertension (+ 8.3% vs. + 3.6%; p < 0.001 for both), atrial fibrillation (+ 2.6% [p < 0.01] vs. + 0.3% [p < 0.001]), and use of proton pump inhibitors (+ 11.5% vs. + 9.0%), anti-hypertensives (+ 9.9% vs. + 1.4%) and warfarin (+ 3.2% vs. + 0.4%); p < 0.001 for CRC cases and non-cases with respect to each medication. CONCLUSIONS: CRC incidence has remained relatively stable in the UK over the last decade. The increased prevalence of some comorbidities and medications among CRC cases should be considered when evaluating patterns in CRC survival.

Cardiovascular outcomes for patients with symptomatic peripheral artery disease: A cohort study in The Health Improvement Network (THIN) in the UK.

Background Few data are available on risk factors and associations with outcomes in symptomatic peripheral artery disease (PAD) populations in primary care. We assessed characteristics and cardiovascular outcomes in patients with and those without symptomatic peripheral artery disease in UK primary care, and quantified risk factors for cardiovascular outcomes in patients with peripheral artery disease. Methods Among patients in The Health Improvement Network (THIN) aged 50-89 years in 2000-2010, a symptomatic peripheral artery disease cohort ( n = 28,484) and a matched comparison cohort without peripheral artery disease ( n = 113,940) were identified using Read codes. Cox proportional hazard ratios (HRs) and 95% confidence intervals (CIs) for cardiovascular outcomes were calculated, adjusted for potential confounders. Results The incidence of all-cause death per 1000 person-years was 83.22 and 50.46 in the peripheral artery disease and non-peripheral artery disease cohort, respectively (HR 1.41; 95% CI 1.68-1.43). The incidence of composite cardiovascular outcome (myocardial infarction, ischaemic stroke or cardiovascular-related death) per 1000 person-years was 31.87 and 14.63 in the peripheral artery disease and non-peripheral artery disease cohort, respectively (HR 1.71; 95% CI 1.65-1.77). Risk factors for composite cardiovascular outcome in patients with peripheral artery disease were older age (≥75 years vs. 50-64 years: HR 2.37; 95% CI 2.20-2.55), current smoking (1.26; 1.17-1.35), comorbid diabetes (1.42; 1.32-1.52), heart failure (1.31; 1.20-1.44), atrial fibrillation (1.32; 1.18-1.47, previous myocardial infarction (1.29; 1.20-1.39) and previous ischaemic stroke (1.77; 1.63-1.93). Conclusion Patients with symptomatic peripheral artery disease in a clinical practice population have a high risk of death and cardiovascular-related outcomes. Minimising risk is important in the ongoing management of these patients.

New use of low-dose aspirin and risk of colorectal cancer by stage at diagnosis: a nested case-control study in UK general practice.

BACKGROUND: Evidence from clinical trial populations suggests low-dose aspirin reduces the risk of colorectal cancer (CRC). Part of this reduction in risk might be due to protection against metastatic disease. METHODS: We investigated the risk of CRC among new-users of low-dose aspirin (75-300 mg), including risk by stage at diagnosis. Using The Health Improvement Network, we conducted a cohort study with nested case-control analysis. Two cohorts (N = 170,336 each) aged 40-89 years from 2000 to 2009 and free of cancer were identified: i) new-users of low-dose aspirin, ii) non-users of low-dose aspirin, at start of follow-up, matched by age, sex and previous primary care practitioner visits. Patients were followed for up to 12 years to identify incident CRC. 10,000 frequency-matched controls were selected by incidence density sampling where the odds ratio is an unbiased estimator of the incidence rate ratio (RR). RRs with 95% confidence intervals were calculated. Low-dose aspirin use was classified 'as-treated' independent from baseline exposure status to account for changes in exposure during follow-up. RESULTS: Current users of low-dose aspirin (use on the index date or in the previous 90 days) had a significantly reduced risk of CRC, RR 0.66 (95% CI 0.60-0.74). The reduction in risk was apparent across all age groups, and was unrelated to dose, indication, gender, CRC location or case-fatality status. Reduced risks occurred throughout treatment duration and with all low-dose aspirin doses. RRs by aspirin indication were 0.71 (0·63-0·79) and 0.60 (0.53-0.68) for primary and secondary cardiovascular protection, respectively. Among cases with staging information (n = 1421), RRs for current use of low-dose aspirin were 0.94 (0.66-1.33) for Dukes Stage A CRC, 0.54 (0.42-0.68) for Dukes B, 0.71 (0.56-0.91) for Dukes C, and 0.60 (0.48-0.74) for Dukes D. After 5 years' therapy, the RR for Dukes Stage A CRC was 0.53 (0.24-1.19). CONCLUSIONS: Patients starting low-dose aspirin therapy have a reduced risk of Stages B-D CRC, suggesting a role for low-dose aspirin in the progression of established CRC; a substantial reduction in the risk of Dukes A CRC may occur after 5 years' therapy.

Incidence, treatment and recurrence of endometriosis in a UK-based population analysis using data from The Health Improvement Network and the Hospital Episode Statistics database.

PURPOSE: This retrospective study used medical records from The Health Improvement Network (THIN) and Hospital Episode Statistics (HES) database to evaluate endometriosis (incidence, treatment and need for recurrent invasive procedures) in the general UK population. MATERIALS AND METHODS: Women aged 12-54 years between January 2000 and December 2010, with a Read code for endometriosis, were identified in THIN. Cases were validated by manual review of free-text comments in medical records and responses to physician questionnaires. False-negative cases were identified among women with Read codes for hysterectomy or dysmenorrhea. Prescriptions of medical therapies for endometriosis were identified in THIN. Cases of single and recurrent invasive procedures were identified in women with medical records in both THIN and HES. RESULTS: Overall, 5087 women had a Read code for endometriosis, corresponding to an incidence of 1.02 (95% confidence interval [CI]: 0.99-1.05) per 1000 person-years. After case validation, the estimate was 1.46 (95% CI: 1.43-1.50) per 1000 person-years. Medical therapy was prescribed to 55.5% of women with endometriosis in the first year after diagnosis. In total, 48.3% of women received invasive treatment during the study period; approximately one-fifth of these women required further invasive treatment, mainly in the 3 years after the index procedure. CONCLUSIONS: Using Read codes as the only method to identify women with endometriosis underestimates incidence. Over half of women with recorded endometriosis are prescribed medical therapy in the first year after diagnosis. Women with diagnosed endometriosis are at risk of requiring recurrent invasive procedures.

Incidence of colorectal cancer in new users and non-users of low-dose aspirin without existing cardiovascular disease: A cohort study using The Health Improvement Network.

BACKGROUND: Evidence regarding the chemo-protective effects of aspirin has influenced expert opinion in favour of low-dose aspirin use in certain patient populations without cardiovascular disease (CVD). The effects of aspirin in reducing the incidence of colorectal cancer (CRC) may be a large contributor to this favourable risk-benefit profile of low-dose aspirin in primary CVD prevention. METHODS: Using The Health Improvement Network, we estimated the incidence of CRC in individuals free of CVD and either prescribed or not prescribed prophylactic low-dose aspirin. Two cohorts - new-users of low-dose aspirin (N=109,426) and a comparator cohort of non-users (N=154,056) at start of follow-up - were followed (maximum 13years) to identify incident CRC cases. Individuals with a record of CVD, cancer or low-dose aspirin prescription before start of follow-up were excluded. RESULTS: 2330 incident cases of CRC occurred; 885 in the aspirin cohort and 1445 in the comparator cohort, after mean follow-ups of 5.43years and 5.17years, respectively. Incidence rates of CRC per 10,000 person-years (95% confidence interval) were 14.90 (13.95-15.92) in the aspirin cohort and 18.15 (17.24-19.12) in the comparator cohort; incidence rate ratio 0.82 (0.76-0.89) adjusted for age, sex and primary care practitioner (PCP) visits in the previous year. Lower incidence rates were seen in the aspirin cohort for all strata evaluated (gender, age group and number of PCP visits in the previous year) except those aged ≥80years. CONCLUSION: Among most individuals without established CVD, initiation of low-dose aspirin is associated with a reduced incidence of CRC.

Mortality in patients who discontinue low-dose acetylsalicylic acid therapy after upper gastrointestinal bleeding.

PURPOSE: Discontinuing low-dose acetylsalicylic acid (ASA) therapy after upper gastrointestinal bleeding (UGIB) may increase the risk of cardiovascular-related death. Our aim was to compare mortality in UK primary care patients who discontinue ASA after UGIB with that in patients who continue therapy. METHODS: ASA users at the time of UGIB and who were alive 30 days after were selected using The Health Improvement Network. Predictors of survival were assessed using adjusted Cox proportional hazards regression models. RESULTS: Of 547 ASA users, half did not re-initiate ASA during a mean follow-up of 4.1 years. Increasing age (a 10% increased risk for each yearly increase in age; hazard ratio [HR]: 1.10; 95% confidence interval [CI]: 1.07-1.14), female sex (HR: 1.61; 95%CI: 1.09-2.38), current smoking (HR: 2.11; 95%CI: 1.23-3.63), heavy alcohol use (HR: 3.31; 95%CI: 1.50-7.31), diabetes mellitus (HR: 1.93; 95%CI: 1.25-3.00), and chronic obstructive pulmonary disease (HR: 1.75; 95%CI: 1.03-2.99) were significantly associated with increased mortality. Most deaths (115/139) occurred in patients taking ASA for secondary prevention. In these patients, mortality tended to be lower among ASA continuer periods (HR: 0.74; 95%CI: 0.34-1.62) and higher among discontinuer periods (HR: 1.37; 95%CI: 0.81-2.30) than among non-users. Current use of clopidogrel was associated with decreased mortality in this population (HR: 0.49; 95%CI: 0.28-0.86). CONCLUSIONS: ASA therapy for secondary prevention should continue after UGIB because the risk of death tends to increase when ASA is stopped. However, a significantly increased risk was not found in these patients, likely owing to the relatively small number of ASA users and deaths that occurred during follow-up. Further studies with larger samples sizes are needed to confirm these findings among UGIB survivors taking ASA at the time of UGIB. Copyright © 2016 John Wiley & Sons, Ltd.

Prescribing of cyproterone acetate/ethinylestradiol in UK general practice: a retrospective descriptive study using The Health Improvement Network.

OBJECTIVE: To investigate prescribing patterns of cyproterone acetate/ethinylestradiol (CPA/EE) in the United Kingdom before and after the 2013 prescribing guidance. STUDY DESIGN: We conducted a retrospective descriptive study in UK general practice. The study population included women with a first prescription (index date) for CPA/EE in The Health Improvement Network in 2011 (N=2760), 2012 (N=2923) and 2014 (N=2341). We evaluated the proportion of new CPA/EE users with (i) a diagnosis of a hyperandrogenic condition, menstrual problem, consultation for contraception management, and other acne treatment, in the year before the index date; and (ii) proportion of new CPA/EE users with concomitant use of another hormonal contraceptive (HC). RESULTS: The percentage of CPA/EE new users with a record of a hyperandrogenic condition was 61% in 2011, 62% in 2012 and 63% in 2014. Corresponding percentages for acne were 51%, 54% and 55%, respectively. When manually reviewing patient records for a sample of CPA/EE new users (n=200), the acne was recorded in 77% of women, hirsutism in 9.5% and polycystic ovary syndrome in 9.5%. Majority of CPA/EE users had a prior acne diagnosis and/or treatment, 76% (n=2091) in 2011, 79% (n=2296) in 2012 and 78% (n=1834) in 2014. Concomitant use of CPA/EE and another HC was rare, 1% of CPA/EE users in 2011 and fewer than 0.5% of CPA/EE users in both 2012 and 2014. CONCLUSIONS: Before and after 2013, the majority of UK women starting treatment with CPA/EE had a condition in line with its approved indication and had received prior acne treatment as per guidance.