Marshfield Epidemiologic Study Area Research Articles

Urological Procedures in Urolithiasis and Their Association with Chronic Kidney Disease.

Epidemiological evidence suggests that patients with urolithiasis are at increased risk for end-stage renal disease (ESRD). It is unclear if urological intervention impacts the progression of chronic kidney disease (CKD). We conducted a retrospective observational cohort study of patients in the Marshfield Epidemiologic Study Area database between January 1991 and May 2007, where 1,340 patients diagnosed with urolithiasis were extracted. Of the 1,340 subjects, 446 had urological procedures for management of urolithiasis. Those that underwent these procedures were compared to those that did not. Cox proportional hazards models adjusted for age, gender, and comorbidities were performed to evaluate the risk for CKD, elevated serum creatinine, and any-cause mortality. Baseline comorbidities in patients with and without procedures were not significantly different except for obesity (P<0.0001). Subjects that underwent procedures were at increased risk for elevated serum creatinine (Hazard Ratio (HR) [95% CI] =1.49 [1.19-1.85]) when compared to those that did not undergo a urologic procedure during the study period. The results did not reveal a significant difference in incidence of CKD or any-cause mortality. Patients who undergo urologic procedures are at increased risk for elevated creatinine. Urological procedures do not appear to impact incidence of CKD or mortality and, in fact, may prevent long-term renal dysfunction.

Epidemiologic trends in medically-attended tree stand fall injuries among Wisconsin deer hunters.

Tree stand falls are the most common injury to hunters in the USA, but there is limited research on the topic. This study examined the 5-year trends in incident tree stand fall injuries in rural north-central Wisconsin and described patient demographics and injury features. A retrospective analysis was conducted on five prior hunting seasons, 2009-2013. Cases were ascertained from electronic health records via natural language processing that identified patients from the Marshfield Epidemiologic Study Area who received medical attention for a tree stand fall. Annual incidence rates were calculated using the number of hunting license holders in the target population, per administrative data from the Wisconsin Department of Natural Resources. There were 16,556-16,902 deer hunters in any given year, with 39 (92% male) confirmed medically-attended tree stand fall injuries in 2009-2013. Injuries mainly occurred in the lower extremities (n=23), and included two fatalities and one paralysis case. The risk of tree stand fall injuries went from 6.0 (95% CI: 3.2, 11.1) per 10,000 hunters in 2009 to 3.6 (95% CI: 1.6, 7.9) per 10,000 hunters in 2013, which was not a significant change over 5 years (p=0.79). Most falls occurred among archery hunters, in the evening and when descending from a tree stand. Cases were demographically similar to the general population of Wisconsin deer hunters. The current seasonal incidence rate of tree stand fall injuries is relatively low in rural Wisconsin, but with limited signs of improvement. Continued efforts are needed to promote the long-term safety of the hunting public.

Identifying Performance Gaps in Comorbidity and Risk Factor Screening, Prevention, and Counseling Behaviors of Providers Caring for Children with Psoriasis.

Comorbidities and risk factors are associated with pediatric psoriasis. It is unknown whether pediatricians and dermatologists ask about, record, or counsel on pediatric psoriasis risk factors and comorbidities. The aim of our study was to assess the rate at which pediatricians and dermatologists inquire about, counsel on, and document pediatric psoriasis risk factors and comorbidities in a stable population. This was a retrospective chart review from 2011 to 2013 in a large, rural multidisciplinary clinic, the Marshfield Epidemiologic Study Area. Participants were children ages 18 years and younger with plaque psoriasis. Rates of counseling and screening for pediatric psoriasis risk factors and comorbidities by pediatricians and dermatologists were determined. Thirty patients qualified for the study. Data were collected on body mass index (BMI) and tobacco exposure. Caregiver counseling rates on these factors were low; 66.7% and 60% did not receive counseling on BMI reduction or family member smoking cessation, respectively. Counseling on stress as a risk factor was performed at only one patient's dermatology visit (3.3%). Lipid panels were collected for 40% of patients and fasting glucose levels for 33.3% since the date of first psoriasis diagnosis. Blood pressure was collected for all patients. Only 13.3% of patients were counseled on the psoriasis comorbidity hyperlipidemia, 10% on hypertension, and 3.3% on diabetes mellitus. Dermatologists and pediatricians have a low rate of counseling, documenting, and screening for pediatric psoriasis risk factors and comorbidities, suggesting that psoriasis comorbidity education is an aspect of the patient visit that may need improvement. Pediatric psoriasis counseling and screening guidelines are needed.

Validation of Health Event Capture in the Marshfield Epidemiologic Study Area.

In this study, health event capture is broadly defined as the degree to which a group of people use a particular provider network as their primary source of health care services. The Marshfield Epidemiologic Study Area (MESA) is a valuable resource for population-based health research, but the completeness of health event capture has not been validated in recent years. Our objective was to determine the current level of outpatient and inpatient health event capture by Marshfield Clinic (MC) facilities and affiliated hospitals for people living within MESA. A stratified sample survey with strata defined by MESA region (Central or North) and age group (<18 years or ≥18 years). 24 ZIP codes in central and northern Wisconsin, USA. 2,485 individuals participated of the 4,313 sampled cohort members residing in MESA Central (N=61,041) and MESA North (N=25,906) on February 22, 2011. A health care utilization survey was mailed to a random sample stratified by age group and MESA region. Telephone interviews were attempted for nonrespondents. The survey requested information on sources of outpatient care and overnight hospital admissions. Population proportions representing health event capture metrics and corresponding 95% confidence intervals (CI) were estimated with analytic weights applied to account for the survey design. Among those with an outpatient visit during the past 24 months, the most recent visit of an estimated 93% (95% CI, 91% - 94%) was at a MC facility. The most recent admission of an estimated 93% (95% CI, 90% - 96%) of those hospitalized in the past 24 months was at a hospital affiliated with MC. The proportion admitted to MC affiliated hospitals was higher for residents of MESA Central (97%) compared to MESA North (83%). A high proportion of outpatient visits and inpatient admissions in MESA Central and MESA North are accessible in the MC electronic health record. This pattern of high health event capture has been demonstrated since the inception of MESA in 1991. The results from this study validate and support the continued use of MESA for population-based epidemiologic and clinical research.

Aspirin overutilization for the primary prevention of cardiovascular disease.

BackgroundAspirin is commonly used for the primary prevention of cardiovascular disease (CVD) in the US. Previous research has observed significant levels of inappropriate aspirin use for primary CVD prevention in some European populations, but the degree to which aspirin is overutilized in the US remains unknown. This study examined the association between regular aspirin use and demographic/clinical factors in a population-based sample of adults without a clinical indication for aspirin for primary prevention.MethodsA cross-sectional analysis was performed using 2010–2012 data from individuals aged 30–79 years in the Marshfield Epidemiologic Study Area (WI, USA). Regular aspirin users included those who took aspirin at least every other day.ResultsThere were 16,922 individuals who were not clinically indicated for aspirin therapy for primary CVD prevention. Of these, 19% were regular aspirin users. In the final adjusted model, participants who were older, male, lived in northern Wisconsin, had more frequent medical visits, and had greater body mass index had significantly higher odds of regular aspirin use (P<0.001 for all). Race/ethnicity, health insurance, smoking, blood pressure, and lipid levels had negligible influence on aspirin use. A sensitivity analysis found a significant interaction between age and number of medical visits, indicating progressively more aspirin use in older age groups who visited their provider frequently.ConclusionThere was evidence of aspirin overutilization in this US population without CVD. Older age and more frequent provider visits were the strongest predictors of inappropriate aspirin use. Obesity was the only significant clinical factor, suggesting misalignment between perceived aspirin benefits and cardiovascular risks in this subgroup of patients. Prospective studies that examine cardiac and bleeding events associated with regular aspirin use among obese samples (without CVD) are needed to refine clinical guidelines in this area.

Identifying opportunities to improve aspirin utilization for the primary prevention of cardiovascular disease in a regional health care system.

Aspirin is an important part of primary cardiovascular disease prevention, but little is known about aspirin use patterns in regional health care systems. This study used electronic health records from Marshfield Clinic to identify demographic, geographic, and clinical predictors of aspirin utilization in central Wisconsin adults without cardiovascular disease. A cross-sectional design was employed using 2010-2012 data from patients in the Marshfield Epidemiologic Study Area. Individuals who took aspirin-containing medication daily or every other day were considered regular aspirin users. There were a total of 6678 adults in the target region who were clinically indicated for aspirin therapy for primary cardiovascular disease prevention, per national guidelines. Aspirin was generally underutilized in this population, with 35% of all clinically indicated adults taking it regularly. Adjusted models found that individuals who were younger, female, not covered by health insurance, did not visit a medical provider regularly, smokers, were not obese, or did not have diabetes were least likely to take aspirin. In addition, there was some local variation in that aspirin use was less common in northeastern communities within the regional service area. Several aspirin use disparities were identified in central Wisconsin adults without cardiovascular disease, with particularly low utilization observed in those without diabetes and/or without regular physician contact. Methods of using electronic health records to conduct primary care surveillance as outlined here can be adopted by other large health care systems in the state to optimize future cardiovascular disease prevention initiatives.

Wolff-Parkinson-White syndrome and antidromic atrioventricular reentrant tachycardia

This editorial refers to ‘Incidence and prognostic significance of spontaneous and inducible antidromic tachycardia’ by B. Brembilla-Perrot et al. , on page 871. The prevalence of regular paroxysmal supraventricular tachycardia (SVT) is 2.25/1000 persons and the incidence is 35/100 000 person-years, according to data from the Marshfield Epidemiologic Study Area. Thus, there are ∼570 000 patients, and 89 000 new cases/year with SVT in the US alone. In most parts of the world, atrioventricular reentrant tachycardia (AVRT), due to Wolff–Parkinson–White (WPW) syndrome or a concealed accessory pathway, is the second most common cause of SVT (after AV nodal reentrant tachycardia), and accounts for up to one-third of all SVT. In China, WPW syndrome is the most common cause of SVT, being responsible for more than 70% of cases.1 In Western countries, the prevalence of WPW syndrome is 0.1–0.3%.1 Thus, despite the fact that accessory pathways have been continually eliminated in electrophysiology laboratories during the last two decades, WPW syndrome is not likely to become extinct. Clear indications for catheter ablation in patients with WPW syndrome are not established. In patients with asymptomatic pre-excitation, the risk of sudden cardiac death is low, ∼1.25/1000 person-years.2 Symptomatic patients have …

Urolithiasis in a Rural Wisconsin Population From 1992 to 2008: Narrowing of the Male-to-Female Ratio

Urolithiasis is a common disease with multiple etiologies and risk factors. Studies suggest an increased incidence in developed nations in recent decades as well as differential geographic incidence and prevalence rates, and differences between the genders. We updated urolithiasis epidemiological data by examining the incidence and prevalence rates in a stable rural Wisconsin population. Data were obtained from the Marshfield Epidemiologic Study Area database, a surveillance tool created in 1991 to track disease in residents of an area of 24 ZIP Codes including approximately 85,000 individuals, of whom most receive care at Marshfield Clinic and affiliates. Urolithiasis cases were identified using ICD-9 codes. Incidence, prevalence and recurrence rates were determined. The mean age adjusted incidence of new onset urolithiasis per 100,000 person-years was 202 (95% CL 168-235) in 1992 and 289 (95% CL 253-325) in 2008. In women the increase per 100,000 person-years was higher than in men, that is 171 (95% CL 129-213) and 289 (95% CL 238-340) vs 238 (95% CL 184-290) and 296 (95% CL 244-348), respectively. The male-to-female incidence ratio decreased from 1.4 to 1.0. The age adjusted prevalence per 100,000 individuals was 1,968 (2%) and 3,554 (3.5%) in 1992 and 2008, respectively. The increase in women was higher than in men (52% vs 26%). The age adjusted recurrence rate per 100,000 individuals was 553 (0.72%) and 676 (1.0%) in 1992 and 2008, respectively. The increase in women was higher than in men (88% vs 20%). Since 1992, urolithiasis incidence, prevalence and recurrence rates in this rural Wisconsin population have increased with higher increases noted in women. While prevalence increased, it was lower than reported in other geographic areas in the United States.

PS1-25: Patient Outcomes in Systemic Lupus Erythematosus: A Collaborative Study Fostered by a New CTSA-based Partnership

Introduction: This project catalyzes a strategic partnership between Marshfield Clinic Research Foundation (MCRF) and the University of Wisconsin (UW), supported by an NIH Clinical and Translational Science Award (CTSA), to explore outcomes of systemic lupus erythematosus (SLE) in a community setting. The study pairs pilot funding and study staff from MCRF with a KL2 scholar/rheumatologist from the UW Institute for Clinical and Translational Research (ICTR). The project also uses ICTR-supported core resources at MCRF (Marshfield Epidemiologic Study Area [MESA]) and at UW (biostatistical support). Background: Survival among SLE patients has improved in recent decades, although studies continue to demonstrate excess mortality and cardiovascular disease. Whereas typical SLE studies represent urban tertiary referral populations, this study explores a community base, where the presence and extent of any mortality or cardiovascular excess is not clearly established. A past study described the spectrum of SLE in MESA from 19912001, finding cases were older, were less predominantly female, and had milder disease than in published reports from tertiary referral centers. Methods: Incident cases from 2002–2007 in this rural, population-based cohort are being ascertained and validated using the same American College of Rheumatology diagnostic criteria as the previous study. All incident cases 1991–2007 are being followed longitudinally to examine rates of all-cause and cardiovascular mortality, and of non-fatal cardiovascular events including MI, stroke, or heart failure hospitalization. Outcomes are to be compared with a matched set of MESA cohort members without SLE. Results/Conclusions: Automated data queries identified 167 new potential cases of SLE. After applying proportions of invalidation and non-incidence from the previous study, we estimate there will be an additional 31 incident cases from 2002–2007 to join the 44 cases previously identified. This represents one of only two rural US-based SLE cohorts with reported mortality outcomes. We anticipate that study results will support future funded research opportunities to ultimately inform evidence-based prevention strategies for SLE patients in real-world community practice.

Atrial Flutter Versus Atrial Fibrillation in a General Population: Differences in Comorbidities Associated With Their Respective Onset

Determine and compare the prevalence of known risk factors for cardiovascular disease among unselected individuals presenting with their first ever episode of atrial flutter (AFL) and atrial fibrillation (AF). We evaluated 11 pre-selected clinical variables including age, sex, smoking history and other potential cardiac risk factors. Using the resources of the Marshfield Epidemiologic Study Area, a population-based database, all newly diagnosed cases of either AFL or AF in the region during a 4-year period were identified. Among the 472 incident cases, 76 (16.1%) had AFL and 396 (83.9%) had AF. Compared to those with AF, subjects with AFL were more likely to have had a history of chronic obstructive pulmonary disease (25% vs. 12%, P = 0.006), heart failure (28% vs. 17%, P = 0.05), and smoking (49% vs. 37%, P = 0.06). Hypertension, on the other hand, was more common among individuals with AF (63% vs. 47%, P = 0.01). This study represents the first report to evaluate potential differences in the conditions associated with the development of AFL versus AF. Research into the mechanisms of atrial arrhythmogenesis may lead to improved preventive and therapeutic interventions.

Prevalence of Asthma in a General Population Cohort of Farm Children: Comparison of Estimates Based on Parental Report and Medical Record Review

ABSTRACT Methods of ascertaining and defining asthma in epidemiologic research vary, and the extent of agreement between such measures is not clearly understood. Within a broader investigation of early-life farm exposures and risk of childhood asthma and other atopic conditions, the authors sought to generate and compare population-based estimates of asthma prevalence among farm children using several definitions, based on both parental report and medical chart review. The Marshfield Epidemiologic Study Area (MESA) is a geographically defined, population-based cohort that receives nearly all health care from Marshfield Clinic and affiliated institutions. The region includes about 2200 farms, and over 9500 children aged 5 to 17 years who were born in the region served as the study population. A stratified random sample of 1000 overselecting for likely farm resident children was drawn. Parents of 553 children completed the survey and gave permission to review medical records. Informative records were available for 531 (96%). A weighted analysis provided estimates for the full study population. Asthma ascertainment included parental reports of past asthma diagnosis, history of wheezing, and asthma medication use, as well as documentation of asthma diagnoses and medication use in the medical chart. Prevalence of asthma among farm children using a broad composite definition was 24.8%. Prevalence based on parental reports of a specific asthma diagnosis was 11.2%, whereas medical chart documentation of a past asthma diagnosis was found for 10.1% of farm children. Seventy-one percent of parental reports were validated in the charts, and 80% of chart-confirmed diagnoses were reported by the parent. Basing asthma prevalence for farm children on a history of asthma medication use gave a higher estimate than did history of a diagnosis. Of farm children, 19.2% reported wheezing or respiratory whistling, with 8.1% occurring in the past year. Observational research on asthma can be substantially influenced by ascertainment methods and case definitions. Although prevalence estimates based on a past asthma diagnosis were quantitatively similar for parental reports and chart confirmation, agreement on specific cases between the two sources was less than expected. Care should be taken to clearly describe asthma case definitions when reporting results of observational asthma research.

Barrett's Esophagus: Incidence and Prevalence Estimates in a Rural Mid-Western Population

Barrett's esophagus (BE) predisposes to adenocarcinoma of the esophagus and survival in esophageal adenocarcinoma is low. We studied patients diagnosed with BE in the Marshfield Epidemiologic Study Area (MESA). Our objectives were to estimate the prevalence of diagnosed BE, estimate the annual incidence of initial diagnosis of BE, and characterize the demographics of patients diagnosed with BE. We retrospectively reviewed medical records of patients diagnosed with BE until December 31, 2002. The esophagogastroduodenoscopy (EGD) reports were reviewed to establish the presence of columnar epithelium. All slides were retrieved and reviewed by a gastrointestinal pathologist to establish the presence of intestinal metaplasia and dysplasia. Chart abstraction was conducted using a standardized form. BE was histologically confirmed in 216 patients. All were white, 165 (76%) were male, and 81% had a hiatal hernia. Median age at diagnosis was 65.5 yr (range 17-94). Long-segment BE (LSBE) was present in 112 (51.9%) patients. The prevalence of histologically confirmed BE in MESA was 261.8 (95% CI 222.5-301.1) per 100,000 people. The incidence of an initial diagnosis of BE between 1996 and 2002 was 32.7 per 100,000 person-years (95% CI 27.1-38.2) and did not change significantly over the study period despite an increase in EGD rates. At the initial diagnosis, 41.7% of the patients were on proton pump inhibitors. Dysplasia was present in 24.5% of patients. The incidence of initial diagnosis of BE in a stable white population did not change significantly over a 7-yr period, despite an increase in EGD rates.

Prevalence and mortality of patients with myocardial infarction and reduced left ventricular ejection fraction in a defined community: Relation to the second multicenter automatic defibrillator implantation trial

We compared characteristics and mortality of patients from a community population meeting enrollment criteria of the second Multicenter Automatic Defibrillator Implantation Trial (MADIT II) to those of the MADIT II subjects. MADIT II showed that implantable cardioverter-defibrillators (ICDs) reduce mortality in patients with myocardial infarction (MI) and low left ventricular ejection fraction (LVEF) <or=30%. We used the resources of the Marshfield Epidemiologic Study Area (MESA), a well defined geographic region to identify MADIT II-type patients and determined outcomes during a 2-year follow-up period. Of 1,126 patients who survived an MI, 114 (10.1%) had an LVEF <or=30%, 30 had exclusions leaving 84 patients meeting MADIT II-eligibility with a prevalence of 1.95/1,000. Applied to the US population, there would be about 360,000 MADIT II eligible individuals. MESA patients were older and more likely to be women than their MADIT II counterparts. The cumulative probability of death at 2 years in MESA patients (22.7%) was similar to the MADIT II control group (22%), whereas the sudden cardiac death (SCD) rate was lower in MESA (2.6%) than in MADIT II control patients (12%). Differences in demographics, clinical characteristics and risk of SCD in community patients could alter the effectiveness and cost-effectiveness of ICD therapy from results reported in clinical trials. Further research is urgently needed to determine if the evidence-base used to formulate practice guidelines should be generalized to all individuals who meet eligibility criteria for ICD therapy.

Acute health events in adult patients with genetic disorders: The Marshfield Epidemiologic Study Area

PurposeWe ascertained and reviewed acute health events occurring in 2003 among patients age 18 and greater with well-defined single gene, chromosomal, and selected multifactorial conditions within the Marshfield Epidemiologic Study Area. MethodsOf 47,077 adult Marshfield Epidemiologic Study Area Central cohort members, 1831 (3.9%) had been given at least one of 71 ICD-9 codes appropriate for genetic diagnoses of interest. Physician review narrowed this to 591 (1.3%) validated patients for the study. Of the 591, 527 (89.2%) patients registered 6,849 visits, which were manually reviewed to delineate acute, relevant health events in the urgent care and primary care provider setting. ResultsA total of 244 acute relevant health events among 126 patients corresponding to 58 different genetic conditions were observed. Acute relevant health events corresponded to 3.4% of the total health events in patients identified with genetic problems. Categories of genetic conditions with the highest frequencies of acute relevant health events included chromosomal and microdeletion syndromes (21.3%), hematologic disorders (11.5%), muscular dystrophies (8.6%), and connective tissue disorders (10.2%). ConclusionsThese data have multiple applications and implications in addressing the natural history, long-term medical needs and financial impact of adult patients with genetic conditions.

Epidemiology of systemic lupus erythematosus in rural Wisconsin

We investigated the epidemiology of systemic lupus erythematosus (SLE) in the Marshfield Epidemiologic Study Area (MESA), a defined rural region where nearly all residents obtain their health care from a large clinic system. Computerized medical records were searched to identify MESA residents diagnosed with SLE from 1991 through 2001. Medical records were manually reviewed for all selected patients to identify cases of SLE using the 1982 revised American College of Rheumatology criteria. Patients with > or = 4 criteria were classified as definite SLE. Age- and gender-specific SLE incidence rates (1991-2001), the population prevalence rate of SLE on 31 December 2001 and survival rates were calculated. We identified 117 MESA residents with definite SLE. The average age-adjusted incidence of definite SLE was 5.1 per 100 000 per year (95% CI: 3.6, 6.6) and the age-adjusted population prevalence was 78.5 per 100 000 (95% CI: 59.0, 98.0). The mean age at diagnosis among the 44 incident cases was 51.7 years (range: 14-90 years). Positive anti-nuclear antibody (ANA), hematologic abnormalities, arthritis and renal disease were common at diagnosis. Five- and 10-year survival rates were 88% and 76%, respectively. Epidemiologic characteristics of SLE in this rural Caucasian population are generally similar to those reported by other US studies. One notable difference is a relatively high incidence of SLE in older adults.

Psychosocial Work Characteristics Predict Cardiovascular Disease Risk Factors and Health Functioning in Rural Women: The Wisconsin Rural Women's Health Study

The aim of the present study is to investigate the association between psychosocial work characteristics and health functioning and cardiovascular disease risk factors among rural women of central Wisconsin and compare psychosocial work characteristics between farm and nonfarm women. Stratified sampling was used to select a random sample (n = 1500) of farm and nonfarm women aged 25 to 71 years from the Central Marshfield Epidemiologic Study Area. The baseline examination included measurements of blood pressure, height, weight, and fasting blood lipids, glucose, and insulin. Psychosocial job condition was measured with the Karasek Job Content Questionnaires (JCQ). Health functioning was assessed by the Short Form-36 Health Survey. The analysis of JCQ showed that nonfarm residents were more likely to have jobs with high demand and high decision latitude compared to farm residents. Also, the farm residents (40.3%) were more likely to be occupied in passive jobs (jobs with low levels of demand and control) than the nonfarm residents (26.9%). Among farm residents, psychological job demand was associated with HDL level (beta = 0.17), triglycerides (beta = 0.0), their ratio (beta = 0.005), and blood insulin level (beta = 0.014), and among nonfarm residents, psychological job demand was associated with diastolic blood pressure (beta = 0.17) and total cholesterol level (beta = 0.002). Our results showed that rural farm residents had a higher prevalence of CVD risk factors and were more likely to be occupied in jobs with low levels of demand and control. Job stress predicted more CVD risk factors among farm residents compared to nonfarm residents. Therefore, interventions reducing job strain among rural farm residents are timely and necessary.

Farm Health Surveillance in the Marshfield Epidemiologic Study Area: A Pilot Study

Surveillance of agricultural work-related illness and non-fatal injuries is limited and considered to be a major gap in prevention and policy-making capacity. This pilot study evaluated the utility of the Marshfield Epidemiologic Study Area (MESA) and its farm residency cohort to identify and monitor potential priorities for prevention and control. MESA is a defined geographic region that serves as a resource for conducting population-based health research. Nearly all of the residents receive their health care from the Marshfield Clinic and affiliated hospitals, providing archived electronic medical information to characterize past and present diagnoses. Based on scientific literature and national research priorities, five broad health issues (injuries, back problems, hearing loss, respiratory conditions, and dermatologic conditions) were selected. To estimate age-specific and age-adjusted incidence and prevalence, we followed a fixed cohort of 1995 MESA residents through 2002. Standardized incidence ratios and standardized prevalence ratios were also estimated to quantify the potential impact of farm residency. Linking MESA, its farm residency cohort, and the clinic's data archives allowed successful identification of significant associations with agricultural exposure for a few conditions and subconditions related to consensus priorities in agricultural health, particularly among men. These included extrinsic alveolitis, organic dust toxic syndrome, back pain, osteoarthrosis, and certain injuries. However, the system was generally not able to demonstrate strong influence of farm residency on disease occurrence for many conditions specifically selected for their likely capacity to show such influence. Future surveillance systems should supplement clinical data with other sources of information on health events and should be adequately powered to focus on narrower ranges of health conditions.

The incidence of basal cell and squamous cell skin cancers: population-based estimates from the marshfield epidemiologic study area (MESA)

The occurrence of nonmelanoma skin cancer (NMSC) in the general population is not well quantified. Further, common disease coding systems do not distinguish between basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). The Marshfield Epidemiologic Study Area (MESA) is an established resource for population-based research. Nearly all inpatient and outpatient health events in the region in Wisconsin are captured by a single medical care system. The 77,000 residents are fairly representative of U.S. whites. Our goal was to estimate the incidence and nationwide burden of NMSC, with separate estimates for BCC and SCC. Incident cases of NMSC from 1992 to 2001 were identified through archived International Classification of Diseases, 9th revision (ICD-9), codes 173 through 173.9. Cases from 2000 to 2001 were further classified into BCC and SCC through an extensive lexicon system used for all recent medical charting. Rate calculations employed MESA person-time denominators. The 2000 U.S. standard population was used for direct age adjustment. Validation efforts included sample medical chart review and estimation of melanoma incidence for comparison with published rates. With 2287 incident cases of NMSC, the overall age-adjusted incidence rate was 282/100,000 person-years (py) (95% confidence interval CI = 270–293). Incidence increased strongly with age and was about 40% higher for men than women, particularly after age 60. At 189/100,000 py (95% CI = 169–209), BCC was more common than SCC, at 53/100,000 py (95% CI = 43–64). The specificity of NMSC diagnosis codes was high (>90%). The melanoma rate estimate for MESA (23.6/100,000 py) was similar to the published rate for whites in the United States (23.9/100,000 py). Projecting from these data, there may be about 660,000 U.S. whites with incident NMSC each year, including 500,000 with BCC. The total burden of NMSC, including recurrent lesions, would be even larger and can be expected to grow as the population ages. Systematic methods for continued monitoring of this condition should be considered.

Wisconsin Rural Women's Health Study Psychological Factors and Blood Cholesterol Level: Difference between Normal and Overweight Rural Women

The aim of the present study is to investigate the effects of psychological factors on plasma lipid levels among rural women of central Wisconsin and to compare the effects of these variables among normal-weight and overweight women. Stratified sampling was used to select a random sample (n=1500) of farm and non-farm women aged 25 to 71 years from the Central Marshfield Epidemiologic Study Area. The baseline examination included measurements of blood pressure, skin folds, height, weight, and fasting blood lipids, glucose, and insulin. Framingham study questionnaires were employed to measure anger, anxiety, tension, and marital disagreement. The Spielberger Trait anger-reaction subscale was employed to assess proneness to anger. Among normal-weight women, a positive association was found between anger-reaction scores and cholesterol (b=0.008), ratio (b=0.014), triglycerides (b=0.02), and LDL (b=0.07). The odds of elevated cholesterol were highest among women with high scores on the Speilberger anger-reaction scale (OR=2.0) and anger discussion scale (OR=2.0), while the odds were less among women with high scores on the anger-out scale (OR=0.59). However, among overweight women, we found only scores on the Framingham anger-discussion scale as an important factor to determine the plasma lipid levels. Anger management may help to sever the link between psychological factors and CHD risk factors. Intervention intended to prevent cardiac events through the reduction of stress and modification of related psychological risk factors have successfully improved the CHD risk factors profile. Similar studies are needed to determine the efficacy of intervention for the primary prevention of CHD risk factors.

Measuring Disease Frequency in the Marshfield Epidemiologic Study Area (MESA)

The Marshfield Epidemiologic Study Area (MESA) is a rare resource for population-based health and medical research developed at Marshfield Clinic Research Foundation. Because of high population coverage and health event capture, MESA is particularly useful for determining the frequency of disease in the general population. A substantial proportion of MESA-based publications appearing in the peer reviewed literature have reported incidence or prevalence rates of disease or disease-related factors. This paper reviews the first 10 years of MESA's support of meaningful inquiry into the frequency of disease occurrence, and briefly reports on the data and methods used for such calculations using selected chronic diseases as examples. Limitations of MESA estimates are discussed as are alternate methods. Compared to limited data published for the selected conditions, occurrence rates in MESA based on diagnostic codes and general validation rules only appear somewhat high, although the observed temporal trends and relationships with demographics are consistent. Rich clinical data sources are available to be linked with MESA to improve the specificity of case ascertainment, as is typically done for disease-specific publications from MESA.