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Biomedical subjects

R F A Logan

Publications and source records attributed to R F A Logan.

At least 19 recordsLinked to original sources
PubMed2006

Trends in the incidence of primary liver and biliary tract cancers in England and Wales 1971-2001.

In the last two decades, mortality from primary liver cancer has increased in the UK. We aimed to determine whether the incidence trends for these cancers were similar and in particular if the increasing occurrence of cholangiocarcinoma has continued. We calculated directly age-standardised incidence rates (using the European standard population) by subsite and histological type for all cancers of the liver, gallbladder and biliary tract in England and Wales from 1971 to 2001, using cancer registry data. The incidence of cancers of the liver, gallbladder and biliary tract increased, with the greatest rise, around 12-fold, in intrahepatic bile duct cancers. The rate of liver cell cancer increased by around 45% in males, but by <10% in females. There were marked reductions in the incidence of gallbladder and extrahepatic bile duct cancer. Cholangiocarcinoma increased around 16-fold and became the most common type of primary liver cancer in females, while hepatocellular carcinoma remained the commonest type in males. The age-specific incidence rates showed that intrahepatic bile duct cancer continued to increase throughout the 1990s in those aged 75 and over, while liver cell cancer decreased in the older age groups. In conclusion, there were increases in the incidence of primary liver cancer, which have been particularly dramatic for intrahepatic bile duct cancer, over the last three decades of the 20th century in England and Wales. There has been a halving in the incidence of gallbladder cancer and a reduction of a third in extrahepatic bile duct cancer.

Adult↗
PubMed2006

Is an internal comparison better than using national data when estimating mortality in longitudinal studies?

BACKGROUND: Discrepancies between the results of different studies looking at mortality in similar disease cohorts led us to consider the impact of methodology upon outcome. METHODS: Cohort studies were carried out using age, sex, practice, and calendar time matched control groups in the general practice research database. Data were used on all subjects with inflammatory bowel disease, coeliac disease, or Barrett's oesophagus. Mortality data for the population of England and Wales were obtained from the UK Office for National Statistics. The study compared hazard ratios (HR) for mortality using the matched controls to those found when an indirect standardisation to the mortality experience of England and Wales was carried out. RESULTS: For all three conditions the mortality risk was slightly lower when the national population data were used compared with the internal comparison group (coeliac disease HR 1.33 v standardised mortality ratios (SMR) 1.25, Barrett's oesophagus HR 1.32 v SMR 1.32, inflammatory bowel disease HR 1.50 v SMR 1.34). CONCLUSIONS: A bias was found towards underestimating mortality risk when cohort studies use national population death rates as a comparator. Estimates obtained when an internal comparison group has been used are probably more appropriate.

Adult↗
PubMed2005

Autoimmune cholestatic liver disease in people with coeliac disease: a population-based study of their association.

BACKGROUND: Population data supporting an association between the autoimmune cholestatic liver diseases, primary biliary cirrhosis and primary sclerosing cholangitis and coeliac disease, is limited and at times contradictory. AIM: To explore the relationship between coeliac disease and both primary biliary cirrhosis and primary sclerosing cholangitis within the General Practice Research Database, a UK-based longitudinal primary care database. METHODS: We identified 4732 people with diagnosed coeliac disease and 23 620 age- and sex-matched controls within the General Practice Research Database. We calculated the prevalence of primary biliary cirrhosis and primary sclerosing cholangitis for both the coeliac disease and control group. RESULTS: There was a higher prevalence of primary biliary cirrhosis in adults with coeliac disease, compared with controls [0.17% vs. 0.05%, odds ratio 3.63 (95% confidence interval: 1.46-9.04)]. Primary sclerosing cholangitis was also more common in the coeliac disease group [0.04% vs. 0%, fishers exact test (P = 0.03)]. CONCLUSIONS: There was a threefold or greater increase in risk of both primary biliary cirrhosis and primary sclerosing cholangitis in people with coeliac disease compared with the general population. The association with primary biliary cirrhosis was weaker than in some reports and it is difficult on the basis of this study to justify screening patients with coeliac disease for either primary biliary cirrhosis or primary sclerosing cholangitis.

Adult↗
PubMed2005

Fertility and pregnancy-related events in women with celiac disease: a population-based cohort study.

BACKGROUND & AIMS: Previous studies have raised concern about reduced fertility and increased adverse pregnancy-related events in women with celiac disease, but none has estimated overall fertility compared with the general female population. METHODS: We compared computerized primary care data for 1521 women with celiac disease with data for 7732 age- and practice-matched women without celiac disease. We estimated population-based rates of fertility and adverse pregnancy outcomes. RESULTS: Crude fertility rates were 48.2 and 47.7 live births per 1000 person-years for women with and without celiac disease, respectively (rate ratio, 1.01; 95% confidence interval, 0.90-1.14). Age-specific fertility rates showed that women with celiac disease had lower fertility when younger but higher fertility when older compared with women without celiac disease. This increase in relative fertility with increasing age held whether women had treated or untreated celiac disease. Risks of cesarean section (odds ratio, 1.33; 95% confidence interval, 1.03-1.70) and miscarriage (rate ratio, 1.31; 95% confidence interval, 1.06-1.61) were moderately higher in women with celiac disease, but risks of assisted birth, breech birth, preeclampsia, postpartum hemorrhage, ectopic pregnancy, stillbirth, and termination were similar. CONCLUSIONS: Overall, women with celiac disease have fertility similar to that of the general female population, but they have their babies at an older age. Although our findings may reflect a disease effect, the age shift in fertility rates and the increase in cesarean section risk is consistent with socioeconomic or educational advantages of women with celiac disease.

Abortion, Spontaneous↗
PubMed2004

Fracture risk of women with primary biliary cirrhosis: no increase compared with general population controls.

AIM: Patients with primary biliary cirrhosis may be at increased risk of osteoporosis but to what extent this is reflected in an increased fracture risk is unknown. We have enquired about the fracture experience of female primary biliary cirrhosis patients compared with sex- and age-matched controls. METHODS: Patients aged 30-75 with primary biliary cirrhosis and age-matched controls were sent a postal questionnaire asking about their fracture history and details of risk factors for osteoporosis. RESULTS: 85 eligible patients with primary biliary cirrhosis and 116 controls responded. Forty-one per cent of patients with primary biliary cirrhosis and 30% of controls reported ever having had a fracture odds ratio 1.5 (95% confidence interval: 0.80-2.89). Twenty-eight per cent of primary biliary cirrhosis patients and 23.3% of controls reported a fracture after the age of 30, odds ratio 1.2 (95% confidence interval: 0.57-2.56), and 14.1% of primary biliary cirrhosis patients and 12.1% of controls reported a low impact fracture of the long bones or of the vertebrae odds ratio 1.0 (95% confidence interval: 0.31-2.68). CONCLUSIONS: No overall increased fracture risk in patients with primary biliary cirrhosis was observed. As a group, unselected patients with primary biliary cirrhosis do not represent a population at particularly high risk of osteoporotic fracture and thus targeting them for osteoporosis screening and treatment is not justified. Further work investigating subgroups of patients with primary biliary cirrhosis at potentially high risk of osteoporosis, such as those with advanced disease or severe cholestasis is required.

Adult↗
PubMed2004

Risk of vascular disease in adults with diagnosed coeliac disease: a population-based study.

BACKGROUND: It has been suggested that vascular disease mortality may be reduced in coeliac disease because of lower levels of blood pressure, cholesterol and body mass. AIM: To examine whether people with coeliac disease are at reduced risk of various vascular diseases. METHODS: We identified 3,790 adults with diagnosed coeliac disease and 17,925 age- and sex-matched controls in the General Practice Research Database. We estimated odds ratios for diagnosed hypertension, hypercholesterolaemia and atrial fibrillation and hazard ratios for myocardial infarction and stroke. RESULTS: Adults with coeliac disease, compared with controls, were less likely to have had a diagnosis of hypertension [11% vs. 15%, odds ratio 0.68 (95% confidence interval: 0.60-0.76)] or hypercholesterolaemia [3.0% vs. 4.8%, odds ration 0.58 (95% confidence interval: 0.47-0.72)] but slightly more likely to have had atrial fibrillation [2.1% vs. 1.7%, odds ratio 1.26 (95% confidence interval: 0.97-1.64)]. The hazard ratio for myocardial infarction was 0.85 (95% confidence interval: 0.63-1.13), while the hazard ratio for stroke was 1.29 (95% confidence interval: 0.98-1.70). CONCLUSIONS: Although rates of myocardial infarction and stroke were not substantially different, adults with coeliac disease do have a lower prevalence of hypertension and hypercholesterolaemia compared with the general population. The effect of a gluten-free diet on cardiovascular risk factors should be determined before any screening programmes for coeliac disease are instituted.

Adult↗
PubMed2004

Risk of extra-oesophageal malignancies and colorectal cancer in Barrett's oesophagus and gastro-oesophageal reflux.

BACKGROUND: The relationship between Barrett's oesophagus and colorectal cancer and other extra-oesophageal malignancies (EOM) has been a matter of controversy. These relationships have therefore been examined in a prospective study design in the General Practice Research Database. METHODS: Cohorts of patients having Barrett's oesophagus (n=1677), oesophagitis (n=6392), and simple reflux (n=6328), and a standard reference cohort representing the general population in the UK (n=13,416) were selected. The last three cohorts were matched to the Barrett's cohort by general practice, age and sex. Incident outcomes occurring beyond the first year of the follow-up were used for analyses. Hazard ratios and 95% confidence intervals were calculated using Cox's proportional hazards regression. The associations with cataract and oesophageal cancer were explored for comparison. RESULTS: Incident cases of 567 EOM (including 74 colorectal cancers), 448 cataract and 43 oesophageal cancers were used in the final analysis. The relative risks for colorectal cancer compared to the standard reference cohort were 1.16 (0.42-3.21) in the Barrett's cohort, 1.39 (0.76-2.54) in the oesophagitis cohort, and 0.93 (0.45-1.90) in the simple reflux cohort. The corresponding relative risks in the Barrett's cohort were 1.29 (0.90-1.85), 1.60 (1.10-2.32), and 10.56 (5.07-21.99) for EOM, cataract and oesophageal cancer, respectively. CONCLUSIONS: The risk of colorectal cancer was not higher in any of the Barrett's oesophagus, oesophagitis, or reflux cohorts compared to the general population. The explanations for the modest increase in the risk of EOM and cataract in the above cohorts are unclear but they may be mediated by ascertainment bias or shared risk factors.

Aged↗
PubMed2004

Antibiotic use and the development of Crohn's disease.

BACKGROUND: Few environmental determinants of Crohn's disease are well established. Some observational data exist to implicate antibiotic use as a risk factor but these are derived from studies using questionnaires to assess reported antibiotic use that were susceptible to recall bias. We have therefore explored this relationship in prospectively gathered data. METHODS: We selected incident cases of Crohn's disease from the General Practice Research Database with at least five years of data prior to diagnosis. Controls with five years of complete data were randomly selected. Data were extracted on smoking, drug prescriptions, age, sex, and a variety of symptoms and diagnoses that might be indicative of occult Crohn's disease. Logistic regression was used to investigate the relationship between antibiotic use and Crohn's disease. RESULTS: A total of 587 Crohn's disease cases and 1460 controls were available for analysis. We found that antibiotic use 2-5 years pre-diagnosis occurred in 71% of cases compared with 58% of controls (p<0.001), and the median number of courses was two in the cases and one in the controls (p<0.001). Adjusting for age, sex, smoking, and use of other drugs, antibiotic use had an odds ratio of 1.32 (1.05-1.65). We were unable to show specificity to any subgroup of antibacterials. Associations similar to that with antibiotics were also found with oral contraceptive, cardiovascular, and neurological drugs. CONCLUSIONS: We found a statistically significant association between Crohn's disease and prior antibiotic use. This cannot be explained by recall bias, but due to lack of specificity it is unclear whether it is causal.

Adolescent↗
PubMed2004

Hip fractures in patients with inflammatory bowel disease and their relationship to corticosteroid use: a population based cohort study.

BACKGROUND: Inflammatory bowel disease (IBD) is known to be associated with reduced bone density but the extent to which this results in an increased risk of fracture and the contribution of corticosteroid therapy are unclear. We have conducted a large cohort study to address these issues. METHODS: We selected subjects within the General Practice Research Database (GPRD) with a diagnosis of IBD and up to five matched controls for each patient. We derived dates of recorded hip fractures and also information on smoking, use of corticosteroids, and a number of other drugs. We calculated the absolute risk of fracture and the relative risk as a hazard ratio corrected for available confounders by Cox regression. RESULTS: Seventy two hip fractures were recorded in 16 550 IBD cases and 223 in 82 917 controls. Cox modelling gave an unadjusted relative risk of hip fracture of 1.62 (95% confidence interval (CI) 1.24-2.11) for all IBD, 1.49 (1.04-2.15) for ulcerative colitis (UC) and 2.08 (1.36-3.18) for Crohn's disease (CD). Multivariate modelling showed that both current and cumulative use of corticosteroids and use of opioid analgesics confounded this relationship. After adjusting for confounding, the relative risk was 1.41 (0.94-2.11) for UC and 1.68 (1.01-2.78) for CD. CONCLUSION: The risk of hip fracture is increased approximately 60% in IBD patients. Corticosteroid use is a contributor to this, both in the long term as previously recognised and also in an acute reversible manner. The majority of hip fracture risk in IBD patients however cannot be attributed to steroid use.

Adult↗
PubMed2004

Risk of oesophageal cancer in Barrett's oesophagus and gastro-oesophageal reflux.

BACKGROUND AND AIMS: While patients with Barrett's oesophagus develop oesophageal adenocarcinoma more frequently than the general population, it has controversially been suggested that gastro-oesophageal reflux (GORD) itself is a more important determinant of risk. In order to assess the validity of this suggestion, we examined the risk of oesophageal cancer in patients with Barrett's and with GORD compared with the general population in a community based cohort study. METHODS: Cohorts of patients with Barrett's (n = 1677), oesophagitis (n = 6392), and simple reflux (n = 6328), and a reference cohort (n = 13416) were selected from the General Practice Research Database. The last three cohorts were matched to the Barrett's cohort by general practitioner practice, age, and sex. Cox's regression analysis was used to calculate relative risks for oesophageal cancer. Standardised incidence ratio methodology was used to estimate the relative risks for oesophageal adenocarcinoma. RESULTS: A total of 137 oesophageal cancers were identified, of which 94 prevalent cases were excluded. The hazard ratios for oesophageal cancer were 10.6 (5.1-22.0), 2.2 (0.9-5.2), and 1.7 (0.7-4.5) in the Barrett's, oesophagitis, and reflux cohorts compared with the reference cohort, respectively. The corresponding relative risks for oesophageal adenocarcinoma were 29.8 (9.6-106), 4.5 (1.04-19.6), and 3.1 (0.6-14.2). CONCLUSION: Barrett's oesophagus increases the risk of oesophageal cancer approximately 10 times and oesophageal adenocarcinoma approximately 30 times compared with the general population. There is only a modestly increased risk of oesophageal cancer in patients with reflux who have no record of Barrett's oesophagus. Our findings therefore do not support the suggestion that gastro-oesophageal reflux disease itself predisposes to cancer.

Adenocarcinoma↗
PubMed2003

Fracture experience of patients with coeliac disease: a population based survey.

BACKGROUND: While coeliac disease is now recognised as being associated with both osteoporosis and osteomalacia, the size of any increase in the risk of fracture in patients with coeliac disease compared with the general population has not been quantified. AIM: To examine the fracture experience of adults with coeliac disease compared with the general population. SUBJECTS: Patients with coeliac disease diagnosed in adulthood and born before 1950, selected from two large population based disease registers, and age and sex frequency matched controls identified from local general practitioner lists. METHODS: A four page lifestyle and general health questionnaire which included specific questions about fracture experience. RESULTS: Analysis was performed on 244 patients with coeliac disease and 161 controls, giving response rates of 89% and 72%, respectively. Eighty two (35%) coeliac patients and 53 (33%) controls reported ever having sustained one or more fractures, giving an age and sex adjusted odds ratio of 1.05 (95% confidence interval (CI) 0.68-1.62). The most common fracture site reported was the forearm or wrist, with an adjusted odds ratio of 1.21 (95% CI 0.66-2.25) for patients with coeliac disease having had a forearm or wrist fracture. Low trauma fractures were reported by 37 patients with coeliac disease (15.7%) and by 21 controls (13.8%), with an adjusted odds ratio of 1.16 (95% CI 0.65-2.10). The risk of low trauma fracture was slightly higher in coeliac men than women (odds ratio 1.28 compared with 1.12), but this difference was not statistically significant (p=0.84). After adjustment for age, sex, body mass index, and smoking status, patients with coeliac disease reported 13% more low trauma fractures than controls (odds ratio 1.13, 95% CI 0.60-2.12). There was no difference in low trauma fracture risk before and after diagnosis of coeliac disease. CONCLUSION: No overall increased fracture risk in patients with coeliac disease was observed. Although severe osteoporosis may develop in a subset of patients, as a whole patients with coeliac disease do not represent a population at particularly high risk of osteoporotic fracture and thus targeting them for osteoporosis screening and treatment is not justified.

Adult↗
PubMed2003

Seroprevalence, correlates, and characteristics of undetected coeliac disease in England.

OBJECTIVE: To examine the seroprevalence, correlates, and characteristics of undetected coeliac disease in a large adult population sample in Cambridge, UK. METHODS: The Cambridge General Practice Health Study invited individuals from 12 general practices, aged 45-76 years, to attend for a health survey that included a bone density measurement, between 1990 and 1995. A total of 7550 participants' serum samples were tested for antiendomysial antibody (EMA). Seroprevalence of undetected coeliac disease was based on EMA positivity. Differences between EMA positive and negative participants of various physiological correlates and reported characteristics were estimated by multivariate logistic and linear regression and adjusted for age, sex, social class, and smoking behaviour. RESULTS: The seroprevalence of undetected coeliac disease in this general population sample aged 45-76 was 1.2% (95% confidence interval (CI) 0.9-1.4). EMA positive participants (n=87) were on average slightly lighter by 2.2 kg (p=0.08), were more likely to have reported their general health as being "good or excellent" (odds ratio (OR) 1.76 (95% CI 0.90-3.46)), and were less likely to report being a current smoker (OR for current versus never 0.36 (95% CI 0.14-0.90)) than EMA negative participants. EMA positivity was associated with an 8% reduction in mean serum cholesterol (0.5 mmol/l; p<0.01) and reductions in mean haemoglobin (0.3 g/dl; p<0.01), total protein (1.0 g/l; p<0.05), and corrected serum calcium (0.02 mmol/l; p<0.05). There was an increased risk of osteoporosis in EMA positive participants (OR 3.1 (95% CI 1.3-7.2)) and of mild anaemia (OR 4.6 (95% CI 2.5-8.2)) compared with EMA negative participants. CONCLUSIONS: Undetected coeliac disease is likely to affect approximately 1% of the population of England aged 45-76 years, a value similar to several other countries. Those affected report "better health" but they do have an increased risk of osteoporosis and mild anaemia. In contrast, they have a favourable cardiovascular risk profile that may afford protection from ischaemic heart disease and stroke.

Age Distribution↗
PubMed2002

Variation in the CTLA4/CD28 gene region confers an increased risk of coeliac disease.

Susceptibility to coeliac disease involves HLA and non-HLA-linked genes. The CTLA4/CD28 gene region encodes immune regulatory T-cell surface molecules and is a strong candidate as a susceptibility locus. We evaluated CTLA4/CD28 in coeliac disease by genetic linkage and association and combined our findings with published studies through a meta-analysis. 116 multiplex families were genotyped across CTLA4/CD28 using eight markers. The contribution of CTLA4/CD28 to coeliac disease was assessed by non-parametric linkage and association analyses. Seven studies were identified that had evaluated the relationship between CTLA4/CD28 and coeliac disease and a pooled analysis of data undertaken. In our study there was evidence for a relationship between variation in the CTLA4/CD28 region and coeliac disease by linkage and association analyses. However, the findings did not attain formal statistical significance (p = 0.004 and 0.039, respectively). Pooling findings with published results showed significant evidence for linkage (504 families) and association (940 families): p values, 0.0001 and 0.0014 at D2S2214, respectively, and 0.0008 and 0.0006 at D2S116, respectively. These findings suggest that variation in the CD28/CTLA4 gene region is a determinant of coeliac disease susceptibility. Dissecting the sequence variation underlying this relationship will depend on further analyses utilising denser sets of markers.

Abatacept↗
PubMed2002

Interactions between Helicobacter pylori and other risk factors for peptic ulcer bleeding.

AIM: To investigate the role of Helicobacter pylori, expressing the virulence marker CAGA (cytotoxin associated gene product A) in ulcer complications and its interaction with nonsteroidal anti-inflammatory drugs (NSAIDs) and other risk factors. DESIGN: Case control study using conditional logistic regression analysis. SETTING: University and City Hospitals, Nottingham. SUBJECTS: 203 consecutive patients with ulcer bleeding and 203 age- and sex-matched controls. RESULTS: Ulcer bleeding was more likely with positive H. pylori serology (odds ratio = 3.3, 95% CI: 1.7--6.6 for CagA positive, but only OR = 1.6, 95% CI: 0.7-3.7 for CagA negative serology), current smoking (OR 2.2, 95% CI: 1.04-4.7), aspirin < or = 300 mg daily (OR 7.7, 95% CI: 2.8-20.6), all other nonsteroidal anti-inflammatory drugs (NSAIDs: OR 10.6, 95% CI: 3.1-35.7 for < or = 1 defined daily dose lower and OR 22.6, 95% CI: 6.2-82.0 for higher doses) and past ulcer history (OR 5.6, 95% CI: 2.3-14.1). Aspirin < or = 300 mg daily was used by 25.1% of patients vs. 7.4% of controls. Smoking only enhanced risk in the presence of H. pylori, with a synergistic interaction (interaction odds ratio = 4.9, 2.4-9.9, P=0.002). Conversely, risks with non-aspirin NSAIDs were reduced in the presence of H. pylori, particularly if CagA-positive (interaction odds ratio=0.21, 0.05-0.9, P=0.03). CONCLUSIONS: CagA positive H. pylori infection is associated with an increased risk of ulcer bleeding. The risk from non-aspirin NSAIDs is even higher, but is less in H. pylori infected people. Low-dose aspirin is now commonly associated with ulcer bleeding.

Adult↗
PubMed2002

Cigarette smoking and adult coeliac disease.

BACKGROUND: While coeliac disease is clearly induced by dietary gluten ingestion in genetically susceptible individuals, other environmental factors may influence the onset of disease. Two studies have suggested that cigarette smoking has a protective role, but a third has not. METHODS: We examined the relationship between cigarette smoking and coeliac disease in individuals with coeliac disease diagnosed in adulthood from two large population-based disease registers and age and sex-matched controls from local general practitioner lists. Participants were mailed a three-page lifestyle and general health questionnaire. Smoking habits of coeliacs were compared with controls and with habits reported in the Health Survey for England 1995. RESULTS: An inverse association between current smoking and adult coeliac disease was identified (odds ratio: 0.77 (95% CI 0.56-1.06)) and remained when comparing ever smoked versus never smoked (odds ratio: 0.83 (0.68-1.00)). When the smoking habits of the coeliacs were compared with the national figures, the number of coeliacs who currently smoked was 40% lower than expected (smoking ratio 0.60, 0.46-0.78). This inverse association was accounted for by the behaviour of the 35-54-year age group (odds ratio for ever smoked 0.67 (0.51-0.89)). There was no association with having ever smoked in the younger age group (odds ratio: 1.44 (0.75-2.78)) or the older group (odds ratio: 0.92 (0.67-1.26)). CONCLUSIONS: There was an inverse association between adult coeliac disease and cigarette smoking which was accounted for by middle-aged coeliacs having never smoked. These results are consistent with an age-dependent interaction between cigarette smoking and the other environmental factors implicated in coeliac disease, including gluten.

Adolescent↗
PubMed2002

High prevalence of undetected ulcerative colitis: data from the Nottingham fecal occult blood screening trial.

OBJECTIVES: Inflammatory bowel disease (IBD) is usually diagnosed as a result of symptoms but occasionally is found during investigation for other conditions. An earlier report from Nottingham had found a high prevalence of previously undetected "asymptomatic" IBD detected as a result of colorectal cancer screening, and the aim of this study was to reassess the prevalence, symptoms, and outcome in these patients. METHODS: We investigated subjects found to be fecal occult blood (FOB) positive in a randomized trial of FOB screening for colorectal cancer. All FOB-positive subjects were investigated by colonoscopy or flexible sigmoidoscopy and barium enema. Subjects with IBD were referred back to their general practitioner for any further investigation and treatment. RESULTS: Seventy-five thousand two hundred fifty-three subjects (aged 45-74) were sent FOB tests and 44,838 (60%) completed a series of tests on one or more occasions. Of 133,000 test series, 1.5% were positive. During investigation 53 cases of previously undetected IBD (52 of ulcerative colitis) were found; 52% (27/52) had proctosigmoiditis only, whereas 25% (13/52) had pancolitis. Only 17% (9/52) were completely asymptomatic, with a half or more reporting some rectal bleeding (54%) or diarrhea (50%). The overall prevalence of undetected ulcerative colitis was 69/10(5) (95% CI = 50-88/10(5)) in people offered screening and 116/10(5) (95% CI = 85-147/10(5)) in people accepting screening and was higher in men. Of 32 subjects followed up 2-12 yr after diagnosis, 91% (29) continued to have few or no symptoms, with only 12 currently receiving any treatment for their colitis. CONCLUSIONS: In comparison with detected disease, undetected ulcerative colitis is relatively common but does usually cause some symptoms. It generally appears to follow a benign course, but a significant proportion have extensive colitis and may therefore be at an increased risk of colorectal cancer.

Age Distribution↗