W. Scott Harmsen

Risk Factors for Opportunistic Infections in Patients With Inflammatory Bowel Disease

BACKGROUND & AIMS We sought to identify and quantify the clinical factors that were associated with opportunistic infections in inflammatory bowel disease patients. METHODS We identified 100 consecutive IBD patients with opportunistic infections. For each case, 2 matched IBD patients who did not have a history of opportunistic infection were selected as controls. Conditional logistic regression was used to assess associations between putative risk factors and opportunistic infections, presented as odds ratios (OR) and 95% confidence intervals (CIs). RESULTS In univariate analysis, use of corticosteroids (OR, 3.4; 95% CI, 1.8-6.2), azathioprine/6-mercaptopurine (OR, 3.1; 95% CI, 1.7-5.5), and infliximab (OR, 4.4; 95% CI, 1.2-17.1) were associated individually with significantly increased odds for opportunistic infection. Multivariate analysis indicated that use of any one of these drugs yielded an OR of 2.9 (95% CI, 1.5-5.3), whereas use of 2 or 3 of these drugs yielded an OR of 14.5 (95% CI, 4.9-43) for opportunistic infection. The relative risk of opportunistic infection was greatest in IBD patients seen at older than 50 years of age (OR, 3.0; 95% CI, 1.2-7.2, relative to those 24 years or younger). No patient died from opportunistic infection. CONCLUSIONS Immunosuppressive medications, especially when used in combination, and older age are associated with increased risk of opportunistic infections. The absolute risk of opportunistic infection in IBD patients remains to be determined, as does any potential benefit of any preventive strategy.

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

BACKGROUND & AIMS Many centers worldwide have reported an increased incidence of Crohns disease, but population-based data in North America are sparse. We studied the incidence and prevalence of Crohns disease in Olmsted County, Minnesota, and examined temporal trends in incidence and survival. METHODS Residents diagnosed with Crohns disease between 1970 and 1993 were incidence cases, and residents with Crohns 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 Crohns 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 Crohns 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.

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 Crohns 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 ≈1.1 million people with inflammatory bowel disease in the US in 2000. (Inflamm Bowel Dis 2007)

Twenty-five-year survivorship of two thousand consecutive primary Charnley total hip replacements: factors affecting survivorship of acetabular and femoral components.

Background: Charnley total hip arthroplasty has been demonstrated to provide good clinical results and a high rate of implant survivorship for twenty years and longer. Most long-term series are not large enough to stratify the many demographic factors that influence implant survivorship. The purpose of this study was to analyze the effects of demographic factors and diagnoses on the long-term survivorship of the acetabular and femoral components used in Charnley total hip arthroplasty.Methods: Two thousand primary Charnley total hip arthroplasties (1689 patients) were performed at one institution from 1969 to 1971. Patients were contacted at five-year intervals after the arthroplasty. Twenty-five years after the surgery, 1228 patients had died and 461 patients were living. Hips that had not had a reoperation, revision or removal of a component for any reason, or revision or removal for aseptic loosening were considered to have survived. Survivorship data were calculated with use of the method of Kaplan and Meier. Patients were stratified by age, gender, and underlying diagnosis to determine the influence of these factors on implant survivorship.Results: The twenty-five year rates of survivorship free of reoperation, free of revision or removal of the implant for any reason, and free of revision or removal for aseptic loosening were 77.5%, 80.9% and 86.5%, respectively. The twenty-five-year survivorship free of revision for aseptic loosening was poorer for each decade earlier in life at which the procedure was performed; this survivorship ranged from 68.7% for patients who were less than forty years of age to 100% for patients who were eighty years of age or older. Men had a twofold higher rate of revision for aseptic loosening than did women.Conclusions: Age, gender, and underlying diagnosis all affected the likelihood of long-term survivorship of the acetabular and femoral components used in Charnley total hip arthroplasty.

Medical costs in community subjects with irritable bowel syndrome

BACKGROUND & AIMS Costs of management of irritable bowel syndrome (IBS) are unknown. The direct medical charges in community subjects with IBS were estimated. METHODS An age- and sex-stratified random sample of residents of Olmsted County, Minnesota, ranging in age from 20 to 95 years, was mailed a valid self-report questionnaire. Subjects were categorized as having IBS, having some symptoms but inadequate criteria for IBS, and controls. All charges (in 1992 U.S. dollars) for health services rendered in the year before completing the survey were obtained (except outpatient medications). RESULTS A total of 88% of subjects with IBS, 86% of subjects with some symptoms of IBS, and 83% of controls incurred direct medical charges during the study year. The odds of incurring charges were 1.6 times greater in subjects with IBS relative to those without symptoms (P < 0.01) adjusting for age, sex, education, marital status, and employment. Overall median charges incurred by subjects with IBS were

The Epidemiology of Community-Acquired Clostridium difficile Infection: A Population-Based Study

742 compared with

Factors Affecting the Durability of Primary Total Knee Prostheses

429 for controls and

Clinical course and costs of care for Crohn's disease: Markov model analysis of a population-based cohort

614 for subjects with some symptoms. Among those subjects with nonzero charges, there were significant positive associations with age, higher education, and symptom groups (all P < 0.01) but not sex. CONCLUSIONS The economic impact of IBS is significant. A better understanding of the determinants of these costs is needed so that cost-saving strategies can be implemented.

Small-bowel imaging in Crohn's disease: a prospective, blinded, 4-way comparison trial

OBJECTIVES:Clostridium difficile infection (CDI) is a common hospital-acquired infection with increasing incidence, severity, recurrence, and associated morbidity and mortality. There are emerging data on the occurrence of CDI in nonhospitalized patients. However, there is a relative lack of community-based CDI studies, as most of the existing studies are hospital based, potentially influencing the results by referral or hospitalization bias by missing cases of community-acquired CDI.METHODS:To better understand the epidemiology of community-acquired C. difficile infection, a population-based study was conducted in Olmsted County, Minnesota, using the resources of the Rochester Epidemiology Project. Data regarding severity, treatment response, and outcomes were compared in community-acquired vs. hospital-acquired cohorts, and changes in these parameters, as well as in incidence, were assessed over the study period.RESULTS:Community-acquired CDI cases accounted for 41% of 385 definite CDI cases. The incidence of both community-acquired and hospital-acquired CDI increased significantly over the study period. Compared with those with hospital-acquired infection, patients with community-acquired infection were younger (median age 50 years compared with 72 years), more likely to be female (76% vs. 60%), had lower comorbidity scores, and were less likely to have severe infection (20% vs. 31%) or have been exposed to antibiotics (78% vs. 94%). There were no differences in the rates of complicated or recurrent infection in patients with community-acquired compared with hospital-acquired infection.CONCLUSIONS:In this population-based cohort, a significant proportion of cases of CDI occurred in the community. These patients were younger and had less severe infection than those with hospital-acquired infection. Thus, reports of CDI in hospitalized patients likely underestimate the burden of disease and overestimate severity.

The Cumulative Long-Term Risk of Dislocation After Primary Charnley Total Hip Arthroplasty

Background: Failure of total knee arthroplasty is problematic. The purpose of this study was to evaluate the factors that influence the durability of a primary total knee prosthesis.Methods: A survivorship analysis of 11,606 primary total knee arthroplasties carried out between January 1, 1978, and December 31, 2000, was performed. An analysis of patient and implant-related factors affecting survivorship was done with use of a multivariate Cox model.Results: The survivorship was 91% (95% confidence interval, 90% to 91%) at ten years (2943 knees), 84% (95% confidence interval, 82% to 86%) at fifteen years (595 knees), and 78% (95% confidence interval, 74% to 81%) at twenty years (104 knees) following the surgery. Prosthetic survivorship at ten years was 83% for patients fifty-five years of age or less compared with 94% for those older than seventy years of age (p < 0.0001), 90% for those with a diagnosis of osteoarthritis compared with 95% for those with inflammatory arthritis (p < 0.005), and 91% for those with retention of the posterior cruciate ligament compared with 76% for those with substitution of the posterior cruciate ligament (a posterior stabilized prosthesis) (p < 0.0001). Survivorship at ten years was 92% for nonmodular metal-backed tibial components, 90% for modular metal-backed tibial components, and 97% for all-polyethylene tibial components (p < 0.0001). Survivorship at ten years was 92% for prostheses fixed with cement compared with 61% for those fixed without cement (p < 0.0001).Conclusions: Significant risk factors for failure of total knee arthroplasty were the type of implant, age and gender of the patient, diagnosis, type of fixation, and design of the patellar component. In the ideal situation—treatment of a woman over the age of seventy years who has inflammatory arthritis with a nonmodular, metal-backed tibial component, cement fixation, an all-polyethylene patellar component, and retention of the posterior cruciate ligament—the ten-year survivorship of the prosthesis was estimated to be 98% (95% confidence interval, 97% to 99%).Level of Evidence: Prognostic study, Level II-1 (retrospective study). See Instructions to Authors for a complete description of levels of evidence.