Incidence and prognosis of colorectal dysplasia in inflammatory bowel disease: a population-based study from Olmsted County, Minnesota

BACKGROUND AND AIMS: The risk, fate, and ideal management of colorectal dysplasia in inflammatory bowel disease (IBD) remain debated. We estimated the incidence, long-term outcome, and risk factors for progression of colorectal dysplasia (adenomas [adenoma-associated lesions or masses (ALMs)], flat dysplasia, and dysplasia-associated lesions or masses [DALMs]) in a population-based IBD cohort from Olmsted County, Minnesota. MATERIALS AND METHODS: The Rochester Epidemiology Project was used to identify cohort patients with colorectal dysplasia. Medical records were reviewed for demographic and clinical characteristics. Histology slides were reviewed by a pathologist blinded to previous pathology reports. The cumulative incidence of dysplasia was estimated, and the association between patient characteristics and recurrence/progression of dysplasia was assessed using proportional hazards regression. RESULTS: Twenty-nine (4%) IBD patients developed flat dysplasia (n = 8), DALMs (n = 1), ALMs in areas of IBD (n = 18), or ALMs outside areas of IBD (n = 2). Among 6 patients with flat low-grade dysplasia (fLGD) who did not undergo colectomy, none progressed during a median of 17.8 (range 6-21) years of observation with a median of 3 (range 0-12) surveillance colonoscopies. Four (22%) patients with ALMs in areas of IBD who did not undergo surgery developed LGD or DALMs. Primary sclerosing cholangitis and dysplasia located proximal to the splenic flexure were significantly associated with risk for recurrence/progression of dysplasia. CONCLUSIONS: This population-based cohort study from Olmsted County, Minnesota did not confirm an increased risk of cancer related to fLGD, whereas 22% of patients with ALMs in areas of IBD developed fLGD or DALMs.     

Long-term fracture risk in patients with Crohn's disease: a population-based study in Olmsted County,Minnesota

BACKGROUND & AIMS: Osteoporosis is common in patients with Crohn's disease, but less is known about their risk of actual fractures. METHODS: The medical records of all 238 Olmsted County, Minnesota, residents diagnosed with Crohn's disease between 1940 and 1993 were reviewed for evidence of subsequent fractures compared with a control group of county residents matched by age and sex. The risk ratio of fracture in patients relative to controls was estimated using the Cox proportional hazards regression model. The cumulative incidence of fracture following diagnosis was estimated using the Kaplan-Meier method. RESULTS: Sixty-three patients had 117 different fractures. The cumulative incidence of any fracture from the time of diagnosis onward was 36% at 20 years versus 32% in controls (P = 0.792). Compared with controls, the overall risk ratio for any fracture was 0.9 (95% confidence interval [CI], 0.6-1.4), whereas the relative risk for an osteoporotic fracture was 1.4 (95% CI, 0.7-2.7). The risk ratio for thoracolumbar vertebral fracture was 2.2 (95% CI, 0.9-5.5). Cox proportional hazards regression identified only age as a significant clinical predictor of fracture risk (hazard ratio per 10-year increase in age, 1.3; 95% CI, 1.1-1.5). Specifically, use of corticosteroids and surgical resection did not predict risk of fracture among these unselected patients with Crohn's disease from the community. CONCLUSIONS: In this population-based inception cohort of patients with Crohn's disease, the risk of fracture was not elevated relative to age- and sex-matched controls.     

Ulcerative colitis in Olmsted County, Minnesota, 1940-1993: incidence, prevalence, and survival

BACKGROUND: There is significant geographic variation in the reported incidence of ulcerative colitis. AIMS: To update the incidence and prevalence of ulcerative colitis in Olmsted County, Minnesota, examine temporal trends, and determine overall survival. PATIENTS: All Olmsted County residents diagnosed with ulcerative colitis between 1940 and 1993 (incidence cases), and all residents with ulcerative colitis alive on 1 January 1991 (prevalence cases). METHODS: Incidence and prevalence rates were adjusted using 1990 US census figures for whites. The effects of age, sex, and calendar year on incidence rates were evaluated using Poisson regression. Survival from diagnosis was compared with that expected for US north-central whites. RESULTS: Between 1940 and 1993, 278 incidence cases were identified, for an adjusted incidence rate of 7.6 cases per 100 000 person years (95% confidence interval (CI), 6.7 to 8.5). On 1 January 1991, there were 218 residents with definite or probable ulcerative colitis, for an adjusted prevalence rate of 229 cases per 100 000 (95% CI, 198 to 260). Increased incidence rates were associated with later calendar years (p<0.002), younger age (p<0.0001), urban residence (p<0.0001), and male sex (p<0.003). Overall survival was similar to that expected (p>0.2). CONCLUSIONS: The overall incidence rate of ulcerative colitis in Olmsted County increased until the 1970s, and remained stable thereafter. Incidence rates among men and urban residents were significantly higher. The prevalence rate in Rochester in 1991 was 19% higher than that in 1980. Overall survival was similar to that of the general population.     

Crohn's disease in Olmsted County, Minnesota, 1940–1993: Incidence, prevalence, and survival

Background & Aims: Many centers worldwide have reported an increased incidence of Crohn's disease, but population-based data in North America are sparse. We studied the incidence and prevalence of Crohn's disease in Olmsted County, Minnesota, and examined temporal trends in incidence and survival. Methods: Residents diagnosed with Crohn's disease between 1970 and 1993 were incidence cases, and residents with Crohn's disease who were alive on January 1, 1991, were prevalence cases. Cases from previous studies were reconfirmed. Rates were adjusted using 1990 U.S. Census figures for whites. Incidence trends were evaluated with a Poisson regression model. Survival from diagnosis was compared with that expected for U.S. north-central whites. Results: Between 1940 and 1993, 225 incidence cases were identified, for an adjusted incidence rate of 5.8 per 100,000 person-years. On January 1, 1991, there were 145 residents with Crohn's disease, an adjusted prevalence rate of 133 per 100,000, 46% higher than that seen in 1980. Incidence rates before 1964 were significantly lower than those of 1989–1993. Observed survival was less than expected (P = 0.007). Conclusions: The incidence of Crohn's disease has stabilized since the 1970s at a rate higher than that seen previously. Prevalence has increased by 46% since 1980. Overall survival is slightly decreased.GASTROENTEROLOGY 1998;114:1161-1168     

Fracture risk in patients with parkinsonism: a population-based study in Olmsted County, Minnesota.

In this population-based retrospective cohort study, the 138 Olmsted County, Minnesota residents first diagnosed with Parkinson's disease during 1967-79 were matched by age and sex to an equal number of control subjects from the community. Fractures were assessed through review of each subject's complete (inpatient and outpatient) medical records. At the time of diagnosis, County residents with parkinsonism were no more likely to have a history of selected fractures than control subjects (32% in each group). Subsequently, 33% of cases and 20% of controls experienced one or more new fractures during 696 person-years of follow-up (p = 0.008). The greatest increase in risk was seen for proximal femur fractures, confirming previous case-control studies. By 10 years after diagnosis, an estimated 27% of the parkinsonism cohort had experienced a new hip fracture. The pattern of fractures that was observed suggested that the increased risk was due more to specific types of falls than to disuse osteoporosis.     

Update on the incidence and prevalence of Crohn's disease and ulcerative colitis in Olmsted County, Minnesota, 1940-2000

BACKGROUND: We previously reported that the prevalence of Crohn's disease (CD) and ulcerative colitis (UC) in Olmsted County, Minnesota, had risen significantly between 1940 and 1993. We sought to update the incidence and prevalence of these conditions in our region through 2000. METHODS: The Rochester Epidemiology Project allows population-based studies of disease in county residents. CD and UC were defined by previously used criteria. County residents newly diagnosed between 1990 and 2000 were identified as incidence cases, and persons with these conditions alive and residing in the county on January 1, 2001, were identified as prevalence cases. All rates were adjusted to 2000 US Census figures for whites. RESULTS: In 1990-2000 the adjusted annual incidence rates for UC and CD were 8.8 cases per 100,000 (95% confidence interval [CI], 7.2-10.5) and 7.9 per 100,000 (95% CI, 6.3-9.5), respectively, not significantly different from rates observed in 1970-1979. On January 1, 2001, there were 220 residents with CD, for an adjusted prevalence of 174 per 100,000 (95% CI, 151-197), and 269 residents with UC, for an adjusted prevalence of 214 per 100,000 (95% CI, 188-240). CONCLUSION: Although incidence rates of CD and UC increased after 1940, they have remained stable over the past 30 years. Since 1991 the prevalence of UC decreased by 7%, and the prevalence of CD increased about 31%. Extrapolating these figures to US Census data, there were approximately 1.1 million people with inflammatory bowel disease in the US in 2000.     

Gender differences in use of stress testing and coronary heart disease mortality: a population-based study in Olmsted County,Minnesota

Objectives. We sought to examine the utilization of exercise stress testing in relation to age and gender in a population-based setting.Background. The utilization of noninvasive procedures has been shown to be associated with the subsequent use of invasive procedures. Yet, there are no population-based data on the utilization of stress testing; in particular, although gender differences in the use of invasive procedures have been reported, the use of noninvasive procedures has not been examined in relation to gender.Methods. In Olmsted County, Minnesota, passive surveillance of the medical care of the community is provided through the Rochester Epidemiology Project. A population-based cohort of Olmsted County residents undergoing exercise tests was identified. The medical records of residents with prevalent and incident exercise tests in 1987 and 1988 were reviewed. For persons with an initial test (incidence cohort), data on clinical presentation, test indications and results were abstracted. Stress test utilization rates were calculated, and crude rates were directly adjusted to the age distribution of the 1980 U.S. population. To help interpret patterns of use at the population level, coronary heart disease mortality rates (International Classification of Diseases, 9th revision, codes 410 to 414) were calculated (crude and directly adjusted to the overall age distribution of the 1980 U.S. population) and used as an indicator of coronary disease burden.Results. A total of 2,624 tests were performed. The crude utilization rate (per 100,000) was 1,888 for men and 703 for women (rate ratio for men over women 2.7, 95% confidence interval [CI] 2.5 to 2.9); it remained significantly higher in men across all age strata. The crude incidence rate (per 100,000) of initial stress tests was 1,112 for men and 517 for women (rate ratio 2.2, 95% CI 1.9 to 2.4). For both men and women, the incidence increased with age; however, incidence remained lower in women in all age strata. At the time that they underwent an initial test, women were more symptomatic and had poorer exercise performance than men. The rate ratio of men over women for coronary heart disease mortality was 1.1 (95% CI 0.9 to 1.2). The age-adjusted rate ratios for stress test utilization were 2.8 (95% CI 2.5 to 3.0), and that for coronary heart disease mortality was 1.9 (95% CI 1.7 to 2.2).Conclusions. These population-based data show that during the study period, the utilization of stress testing in Olmsted County was lower in women than in men. Women in the incidence cohort were older and more symptomatic and had poorer exercise performance than men. Such differences should be considered when examining the utilization of subsequent invasive procedures according to gender.     

Epidemiologic aspects of Crohn's disease: a population based study in Olmsted County, Minnesota, 1943-1982.

The overall age and sex adjusted incidence of Crohn's disease among Olmsted County, Minnesota, residents was 4.0 per 100,000 person-year in the period 1943-1982. Ileitis, ileocolitis, and colitis each accounted for about one third of the 103 incidence cases. Incidence rates were greater in woman than men, were higher in the urban portions of the county, and rose over time. Overall, the natural history of Crohn's disease in the community may be milder than that reported for patients at referral centres, as over half of all patients had no complications and only a third required surgery for Crohn's disease. Only one developed adenocarcinoma of the colon (relative risk = 2.0, NS). Survival was relatively unimpaired for the cohort, but Crohn's disease may have played a role in half of the deaths. The prevalence of Crohn's disease was 90.5/100,000 population on 1 January 1980.     

Risk factors for colorectal neoplasia in inflammatory bowel disease: a nested case-control study from Copenhagen county, Denmark and Olmsted county, Minnesota

OBJECTIVES: Population-based data on risk factors and protective factors for colorectal dysplasia and cancer in patients with inflammatory bowel disease (IBD) are sparse. We conducted a nested case-control study of such factors in two well-described IBD cohorts from Copenhagen County, Denmark and Olmsted County, Minnesota. METHODS: Forty-three neoplasia cases were matched on six criteria to 1-3 controls (N = 102). Medical records were scrutinized for demographic and clinical data. For each variable, the odds of neoplasia were estimated using conditional logistic regression. RESULTS: Primary sclerosing cholangitis (PSC) (odds ratio [OR] 6.9, 95% confidence interval [CI] 1.2-40), percentage of disease course with clinically active disease (OR [per 5% increase] 1.2, 95% CI 0.996-1.4), and >or=1 yr of continuous symptoms (OR 3.2, 95% CI 1.2-8.6) were associated with neoplasia, whereas a borderline association with median number of small-bowel x-rays (OR 1.3, 95% CI 0.96-1.6) was observed. We did not observe a protective effect of frequency of physician visits (OR 1.4, 95% CI 0.96-2.0), number of colonoscopies (OR 1.4, 95% CI 1.0-2.1), cumulative dose of sulfasalazine (OR [per 1,000 g] 1.1, 95% CI 1.0-1.3) and mesalamine (OR [per 1,000 g] 1.3, 95% CI 0.9-1.9), or partial intestinal resections (OR 1.5, 95% CI 0.3-7.1). CONCLUSIONS: Subgroups of IBD patients-those with PSC, severe long-standing disease, and exposure to x-ray-were at greater risk of colorectal neoplasia. The protective effect of close follow-up, colonoscopy, and treatment with 5-aminosalicylates was questionable.     

Influence of coronary heart disease on morbidity and mortality after carotid endarterectomy: a population-based study in Olmsted County, Minnesota (1970-1988)

To evaluate the prognostic importance of coronary artery disease among patients undergoing carotid endarterectomy, 177 residents of Olmsted County, Minnesota who underwent carotid endarterectomy during the period 1970 through 1988 were followed up to July 1, 1989. Patients were stratified as to the presence (n = 64) or absence (n = 93) of overt coronary artery disease or prior myocardial revascularization (n = 20) at the time of endarterectomy. At 30 days after carotid endarterectomy, there were no significant differences between patients with or without coronary artery disease in the occurrence of death, myocardial infarction or stroke. Kaplan-Meier estimate of 8-year relative survival after carotid endarterectomy (assessed as a percent of survival in age- carotid endarterectomy (assessed as a percent of survival in age- and gender-matched control subjects) was 89% in those without and 75% in those with overt coronary artery disease. Of the 59 total deaths, 29 (49%) had a cardiac cause and 4 (7%) were due to stroke (p less than 0.0001). The cumulative incidence of a cardiac event at 8 years after carotid endarterectomy was greater in those with than in those without overt coronary artery disease (61% vs. 25%, p less than 0.0001). In multivariable analysis, uncorrected coronary artery disease and diabetes were the only independent predictors of subsequent cardiac events, whereas age was the only independent predictor of death. These population-based data suggest that carotid endarterectomy can be safely undertaken in patients with stable coronary artery disease. In long-term follow-up of these patients, coronary rather than cerebral vascular disease is the most frequent cause of morbidity and mortality. Thus, these data lend strong support to the concept of early identification and management of coronary artery disease in patients undergoing carotid endarterectomy.     

Incidence of inflammatory bowel disease in Primorsko-goranska County, Croatia, 2000-2004: A prospective population-based study

OBJECTIVE: It has been suggested that the incidence of inflammatory bowel disease (IBD), which includes ulcerative colitis (UC) and Crohn's disease (CD), is higher in northern than in southern Europe. Recent epidemiological studies showed the loss of the previously described geographical north-south gradient. The aim of this study was to investigate the incidence of UC and CD in Primorsko-goranska County, Croatia. MATERIAL AND METHODS: In the period 1 January 2000 to 31 December 2004 (5 years) all new patients diagnosed with IBD were prospectively identified according to a standard protocol for case ascertainment and definition. A total of 178 residents (81 F, 97 M) were newly diagnosed as having IBD during the study period. Of these, 70 had UC and 100 CD. Eight patients had indeterminate IBD. The data on patients were collected using a data form completed by gastroenterologists. RESULTS: Annual age-standardized incidence rates were 4.3/10(5) (95% CI 2.6-6.0) for UC and 7.0/10(5) (95% CI 3.4-10.6) for CD. The highest incidence rate was observed in the age group 35-44 years for UC and the 25-34 years age group for CD. The incidence of IBD was higher in the urban than in the rural population, with the exception of on the islands. CONCLUSIONS: The incidence of IBD was higher than previously observed in Croatia. Our results suggest that CD incidence rates in the northern coastal part of Croatia are currently comparable with those reported in northern Europe.     

Clinical features and outcome of subacute thyroiditis in an incidence cohort: Olmsted County,Minnesota, study

Subacute thyroiditis (SAT), or granulomatous thyroiditis, is an inflammatory thyroid condition associated with pain and systemic symptoms. Few community studies are available. We studied the 160 patients with SAT in Olmsted County, Minnesota, seen between January 1, 1960, and December 30, 1997. Subjects were identified through the medical diagnostic index of the Rochester Epidemiology Project. The overall age- and sex-adjusted incidence from 1960 through 1997 was 4.9 cases per 100,000/yr. In the most recent 28-yr period (1970-1997), 94 patients were identified. In this group, pain was the presenting symptom in 96%. SAT recurred in 4% of the patients 6-21 yr after the initial episode. Corticosteroid therapy was given to 36%. Early-onset hypothyroidism occurred both in patients receiving corticosteroid therapy (29%) and in those not receiving corticosteroid therapy (37%). At latest follow-up, significantly more patients who had received corticosteroid therapy had a diagnosis of hypothyroidism than the group without corticosteroid therapy (25% vs. 10%, P < 0.05; overall rate of hypothyroidism, 15%). Early transient hypothyroidism is common in SAT. Permanent hypothyroidism is less common, and only 15% of the patients are receiving T(4) therapy after 28 yr of follow-up. Symptomatic relief is achieved with corticosteroid therapy, but such therapy does not prevent early- and late-onset thyroid dysfunction.     

Survival and causes of death in patients with inflammatory bowel disease: a population-based study.

Relative survival up to December 31, 1986 was analyzed for all patients diagnosed with ulcerative colitis (UC) (n = 2,509) and Crohn's disease (CD) (n = 1,469) within the Uppsala Region, Sweden 1965-1983. After 10 years survival was 96% of that expected for UC and CD. Patients with ulcerative proctitis, left-sided colitis, and pancolitis at diagnosis had relative survival rates of 98%, 96%, and 93% respectively. Survival did not differ by extent at diagnosis for patients with CD. After including prevalent cases, 684 deaths occurred compared with 481.1 expected deaths [standardized mortality ratio (SMR) = 1.4; 95% confidence interval (CI) = 1.3-1.5]. Inflammatory bowel disease was the main reason for this excess mortality. Colorectal cancer increased mortality (50 deaths observed vs. 15.2 expected). Death from other cancers were not greater than expected. Obstructive respiratory diseases, especially bronchitis, emphysema, and asthma increased mortality SMR = 1.5 (95% CI = 1.1-2.2) in UC. Cerebrovascular disease mortality occurred less often than expected (SMR = 0.7; 95% CI = 0.5-1.0). Mortality for other diseases and groups of diseases was close to that expected.     

Survival in Danish patients with breast cancer and inflammatory bowel disease: a nationwide cohort study

BACKGROUND: Incidences of inflammatory bowel disease (IBD) and of breast cancer have increased over the last decades. The influence of IBD on breast cancer prognosis, however, is unknown. We therefore examined the impact of IBD on treatment receipt and survival in breast cancer patients. METHODS: Information on breast cancer patients (stage and treatment) diagnosed between 1980 and 2004 was sourced from the Danish Cancer Registry. Data on IBD and potential confounders were extracted from the Danish National Registry of Patients covering all Danish hospitals. Cox regression was used to compute mortality rate ratios (MRRs) among breast cancer patients with IBD, compared to their non-IBD counterparts, adjusting for age, stage, comorbidity measured by the Charlson Index, and calendar year. RESULTS: We identified 71,148 breast cancer cases; 67 also had Crohn's disease (CD) and 216 had ulcerative colitis (UC). Patients with CD had more advanced stage and received radiotherapy less, and chemotherapy more, frequently than patients without IBD. In the adjusted analyses there was no substantial survival difference in breast cancer patients with and without IBD (MRR(CD) = 1.22; 95% confidence interval [CI] = 0.85-1.75; MRR(UC) = 1.09; 95% CI = 0.86-1.38). In a stratified analysis, chemotherapy was associated with poorer survival in patients with CD (MRR(CD) = 1.93; 95% CI = 1.00-3.72). CONCLUSIONS: Breast cancer patients with UC receive the same treatment and have similar survival to breast cancer without IBD. In contrast, breast cancer patients with CD are treated with radiotherapy less often. Survival of breast cancer in patients with CD treated with chemotherapy is poorer compared to survival in patients without IBD.     

General and cancer specific mortality of a population based cohort of patients with inflammatory bowel disease: the Florence study

Background—A population basedepidemiological study identified all the patients diagnosed withulcerative colitis (UC) or Crohn's disease (CD) resident in theFlorence area in the period 1978-1992.
Aims—To assess the mortality of unselectedpatients with inflammatory bowel disease (IBD) in a Mediterranean country.
Methods—Overall, 920 patients (689 UC and 231 CD)were followed until death or end of follow up (31 December 1996).Information on vital status was available for all except eight patients(0.9%); 70 deaths were identified (23 in patients with CD and 47 inpatients with UC). Expected deaths were estimated on the basis of five year age group, gender, and calendar year national mortality rates. Standardised mortality ratios (SMR) and 95% confidence intervals were calculated.
Results—General mortality was significantly lowerthan expected in UC (SMR 0.6; 95% confidence interval 0.4 to 0.8), dueto a reduced number of cardiovascular and, possibly, smoking related deaths. Cancers of the respiratory tract were significantly reduced inUC but tended to be increased in patients with CD. These latter patients had not only an increased cancer mortality but also a 40%increased risk of dying for all causes already evident in the firstfive year follow up period and persisting thereafter. In contrast, inpatients with UC, SMRs were initially very low but tended to increasesteadily over the follow up period. Gastrointestinal deaths wereparticularly increased in patients with CD, but only moderately inthose with UC. Overall, there was some evidence of a twofold increasedmortality for colorectal cancer, the risk being highest for rectalcancers in patients with UC. A non-significant excess of deaths due tohaemolymphopoietic malignancies and suicides was also observed.
Conclusions—This study, the first in aMediterranean country, supports the existence of two divergentmortality patterns for patients with UC and CD, possibly explained bydifferences in smoking habits and by a greater severity of CD.

     

Age- and sex-associated trends in bloodstream infection: a population-based study in Olmsted County, Minnesota

BACKGROUND: Despite increasing concerns about antimicrobial resistance and emerging pathogens among blood culture isolates, contemporary population-based data on the age- and sex-specific incidence of bloodstream infections (BSIs) are limited. METHODS: Retrospective, population-based, cohort study of all residents of Olmsted County, Minnesota, with a BSI between January 1, 2003, and December 31, 2005. The medical record linkage system of the Rochester Epidemiology Project and microbiology records were used to identify incident cases. RESULTS: A total of 1051 unique patients with positive blood culture results were identified; 401 (38.2%) were classified as contaminated. Of 650 patients with cultures deemed clinically relevant, the mean +/- SD age was 63.1 +/- 23.1 years, and 52.5% were male. The most common organisms identified were Escherichia coli (in 163 patients with BSIs [25.1%]) and Staphylococcus aureus (in 108 patients with BSIs [16.6%]). Nosocomial BSIs were more common in males than females (23.8% vs 13.9%; P = .002). The age-adjusted incidence rate of BSI was 156 per 100 000 person-years for females and 237 per 100 000 person-years for males (P<.001), with an age- and sex-adjusted rate of 189 per 100 000 person-years. Rates of BSI due to gram-positive cocci were 64 per 100 000 person-years for females and 133 per 100 000 person-years for males (P<.001); gram-negative bacillus BSI rates (85/100 000 person-years for females and 79/100 000 person-years for males) were not significantly different between sexes (P = .79). The rate of S aureus BSI was 23 per 100 000 person-years for females and 46 per 100 000 person-years for males (P = .005). CONCLUSIONS: There are significant differences in the age and sex distribution of organisms among patients with BSIs. The incidence of BSI increases sharply with increasing age and is significantly higher in males, mainly because of nosocomial organisms, including S aureus.     

The epidemiology of microscopic colitis: a population based study in Olmsted County, Minnesota

OBJECTIVE: Although the epidemiology of microscopic colitis has been described in Europe, no such data exist from North America. We studied the incidence, prevalence and temporal trends of microscopic colitis in a geographically defined US population. DESIGN AND SETTING: In this population based cohort study, residents of Olmsted County, Minnesota, with a new diagnosis of microscopic colitis, and all who had colon biopsies for evaluation of diarrhoea, between 1 January 1985 and 31 December 2001 were identified. Biopsies were reviewed for confirmation (cases) and to identify missed cases (diarrhoea biopsies). MAIN OUTCOME MEASURES: Incidence rates, age and sex adjusted to the 2000 US white population. Poisson regression assessed the association of calendar period, age and sex with incidence. RESULTS: We identified 130 incident cases for an overall rate of 8.6 cases per 100,000 person-years. There was a significant secular trend, with incidence increasing from 1.1 per 100,000 early in the study to 19.6 per 100,000 by the end (p<0.001). Rates increased with age (p<0.001). By subtype, the incidence was 3.1 per 100,000 for collagenous colitis and 5.5 per 100,000 for lymphocytic colitis. Collagenous colitis was associated with female sex (p<0.001) but lymphocytic colitis was not. Prevalence (per 100,000 persons) on 31 December 2001 was 103.0 (39.3 for collagenous colitis and 63.7 for lymphocytic colitis). CONCLUSIONS: The incidence of microscopic colitis has increased significantly over time, and by the end of the study, the incidence and prevalence were significantly higher than reported previously. Microscopic colitis is associated with older age, and collagenous colitis is associated with female sex.     

Secular trends in the epidemiology and outcome of Barrett's oesophagus in Olmsted County, Minnesota

BACKGROUND: The incidence of oesophageal adenocarcinoma has increased greatly. Barrett's oesophagus is a known risk factor. AIMS: To identify changes in the incidence, prevalence, and outcome of Barrett's oesophagus in a defined population. SUBJECTS: Residents of Olmsted County, Minnesota, with clinically diagnosed Barrett's oesophagus, or oesophageal or oesophagogastric junction adenocarcinoma. METHODS: Cases were identified using the Rochester Epidemiology Project medical records linkage system. Records were reviewed with follow up to 1 January 1998. RESULTS: The incidence of clinically diagnosed Barrett's oesophagus (>3 cm) increased 28-fold from 0.37/100 000 person years in 1965-69 to 10.5/100 000 in 1995-97. Of note, gastroscopic examinations increased 22-fold in this same time period. The prevalence of diagnosed Barrett's oesophagus increased from 22.6 (95% confidence interval (CI) 11.7-33.6) per 100 000 in 1987 to 82.6/100 000 in 1998. The prevalence of short segment Barrett's oesophagus (<3 cm) in 1998 was 33.4/ 100 000. Patients with Barrett's oesophagus had shorter than expected survival but only one patient with Barrett's oesophagus died from adenocarcinoma. Only four of 64 adenocarcinomas occurred in patients with previously known Barrett's oesophagus. CONCLUSIONS: The incidence and prevalence of clinically diagnosed Barrett's oesophagus have increased in parallel with the increased use of endoscopy. We infer that the true population prevalence of Barrett's oesophagus has not changed greatly, although the incidence of oesophageal adenocarcinoma increased 10-fold. Many adenocarcinomas occurred in patients without a previous diagnosis of Barrett's oesophagus, suggesting that many people with this condition remain undiagnosed in the community.