The natural history of asymptomatic meningiomas in Olmsted County, Minnesota

To define the natural history of asymptomatic meningioma found incidentally on a neuroimaging study, we performed a retrospective analysis of 35 such patients. There were 32 women and three men, with a mean age of 67 years and a mean follow-up of 74 months. Four tumors had progressed on subsequent imaging, and one patient developed symptoms related to the meningioma. Noncalcified tumors were more likely to progress than calcified tumors.     

Prognostic value of treadmill exercise testing: a population-based study in Olmsted County, Minnesota

BACKGROUND: The prognostic value of treadmill exercise testing (TMET) has been studied in selected populations. The generalizability of these data to different populations and to women is uncertain. METHODS AND RESULTS: A retrospective, population-based cohort study of all persons (1452 men and 741 women) who underwent TMET in years 1987 to 1989 in Olmsted County, Minnesota, was undertaken. Individuals were followed up for all-cause mortality and cardiac events (cardiac deaths, nonfatal myocardial infarction, or congestive heart failure). Sex-specific analyses were performed to determine whether the predictors of outcome and the magnitude of the associations were similar in both sexes. In men, 77 deaths and 106 cardiac events occurred during 8956 person-years of observation; in women, 46 deaths and 54 cardiac events occurred during 4801 person-years of follow-up. Exercise-induced angina, ECG changes, and workload achieved on the TMET were strongly associated with all-cause mortality and cardiac events in both sexes, and the strength of the association was similar. After adjustment, workload was the only TMET variable associated with outcome. A higher workload was associated with a reduction in the risk of cardiac events and of all-cause mortality; the protective effect of exercise capacity was strong and was similar in both sexes. CONCLUSIONS: In this population-based cohort, exercise capacity was the TMET variable that exhibited the strongest association with all-cause mortality and cardiac events. This protective effect of exercise capacity was observed in both sexes.     

Cataract extraction rates in Olmsted County, Minnesota, 1980 through 1994

Management of Q-wave acute myocardial infarction (AMI) has been shown to differ between the United States and Canada, with more catheterization and revascularization procedures performed in the United States, but with little or no apparent difference in clinical outcomes. No previous studies have evaluated management differences for the acute coronary syndromes of unstable angina pectoris and non-Q-wave AMI. We therefore compared treatments and outcomes between 14 United States and 4 Canadian tertiary care centers participating in an observational registry of all consecutive admissions for unstable angina or non-Q-wave AMI between 1990 and 1993. A random, stratified sample was selected for detailed assessment and follow-up. There were 1,733 patients enrolled in United States centers and 642 in Canadian ones. In United States centers patients were less likely to receive intravenous nitroglycerin, heparin, beta blockers, calcium antagonists, or > or = 2 anti-ischemic agents. Coronary arteriography during index hospitalization was equally frequent in both countries (63.4% vs 66.9%, p = 0.781), but at 6 weeks and 1 year coronary arteriography was slightly less frequent in the United States patients. Revascularization by coronary angioplasty or bypass surgery was equivalent at 6 weeks and 1 year; however, there were trends toward less angioplasty and more bypass surgery in the United States than in Canada. Patients at United States centers stayed in the hospital fewer days than patients at Canadian centers (mean 8.2 vs 12.1 days, p <0.001). Death or AMI by 6 weeks was not different (4.8% vs 4.4%, p = 0.633), nor was it different at 1 year (10.0% vs 10.2%, p = 0.836). The combined outcome of death, AMI, or recurrent ischemia was more common in United States than in Canadian patients at 6 weeks (18.4% vs 13.9%, p = 0.004). Our findings indicate that United States physicians and hospitals did not consistently utilize more resources and were not more aggressive than their Canadian counterparts when treating acute coronary syndromes during this period.     

Congestive heart failure in the community: a study of all incident cases in Olmsted County, Minnesota, in 1991

BACKGROUND: Data are limited regarding the classification and prognosis of patients with congestive heart failure (CHF) in the community. METHODS AND RESULTS: Using the resources of the Rochester Epidemiology Project, we evaluated all patients receiving a first diagnosis of CHF in Olmsted County, Minnesota, in 1991 (n=216). Among these patients, 88% were >/=65 years and 49% were >/=80 years of age. The prognosis of patients with a new diagnosis of CHF was poor; survival was 86+/-2% at 3 months, 76+/-3% at 1 year, and 35+/-3% at 5 years. Of the 216 patients, 137 (63%) had an assessment of ejection fraction. In these patients, systolic function was preserved (ejection fraction >/=50%) in 59 (43%) and reduced (ejection fraction <50%) in 78 (57%). Survival adjusted for age, sex, NYHA class, and coronary artery disease was not significantly different between patients with preserved and those with reduced systolic function (relative risk, 0.80; P=0.369). ACE inhibitors were used in only 44% of the total population with CHF. CONCLUSIONS: The present study reports the clinical characteristics and natural history of CHF as it presents in the community in the vasodilator era. CHF is a disease of the "very elderly," frequently occurs in the setting of normal ejection fraction, and has a poor prognosis, regardless of the level of systolic function. Diagnostic and therapeutic methods are underused in the community.     

Timing of completed suicides among residents of Olmsted County, Minnesota, 1951-1985

In man, GHRH has been shown to potentiate the TSH-releasing activity of TRH. To study the way by which GHRH affects TRH-stimulated TSH release, we examined the effect of GHRH (1-29)NH2 on basal and stimulated TSH secretion in intact male rats and superfused dispersed rat pituitary cells. In the intact rats, GHRH(1-29)NH2 potentiated TRH-stimulated TSH release in the evening, but potentiation was not observed in the morning and in dispersed pituitary cells. Basal TSH levels were not changed by GHRH(1-29)NH2. It is concluded that GHRH(1-29)NH2 potentiates the TSH-releasing activity of TRH in the evening in rats possibly through suprahypophyseal disinhibition.     

Incidence and prevalence of intracranial aneurysms and hemorrhage in Olmsted County, Minnesota, 1965 to 1995

OBJECTIVE: To determine the risk of acquiring ventilator-associated pneumonia (VAP) and the impact on costs when extending ventilator circuit change intervals beyond 2 days to 7 and 30 days. DESIGN: Prospective 4-year review of mechanically ventilated patients. SETTING: The respiratory and medical ICUs of an 800-bed tertiary teaching Veterans Affairs hospital. PATIENTS: All adult patients receiving mechanical ventilation from January 1991 through December 1994. INTERVENTIONS: Ventilator circuits with active heated water humidifiers were changed at 2-day intervals during a 2-year control period, followed by 7-day and 30-day intervals (for 1 year each). Heated wire circuits were adopted with the 30-day interval. The rate of VAP per 1,000 ventilator days was calculated for each circuit change interval group. Survival analysis was used to model VAP with ventilator circuit change to determine risk. RESULTS: During the study period, 637 patients received mechanical ventilation. During the 2 years with 2-day change intervals, the VAP per 1,000 ventilator days was 11.88 (n=343), compared with 3.34 (n=137) and 6.28 (n=157) for 7-day and 30-day change intervals, respectively. The risk of acquiring a VAP for those with a circuit change every 2 days was significantly greater (relative risk, 3.1; p=0.0004; 95% confidence interval, 1.662, 5.812) than those with the 7- and 30-day circuit changes. Extending circuit change intervals reduced supply and labor costs averaging $4,231/yr for each ventilator in use. CONCLUSIONS: Circuit change intervals of 7 and 30 days have lower risks for VAP than the 2-day intervals, yielding substantial reductions in morbidity as well labor and supply costs.     

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

The distribution of CD57+ T and CD56+ T cells in patients with RA was examined. In control osteoarthritis patients, these cells exist as a minor population in the peripheral blood. Our data show that in patients with RA, CD57+ T cell levels are elevated in peripheral blood, knee joint fluid, knee synovial membrane and bone marrow (BM), compared with peripheral blood of controls. CD57+ T cells are especially high in knee joint fluid and joint-adjacent BM, while CD56+ T cells show no such increase. CD57+ T cells contain a major population of CD8+ cells and higher proportions of CD4-8- cells and gammadelta T cells than do CD57- T cells. CD57+ T cells in peripheral blood and joint fluid increase with the duration of disease. Erythrocyte sedimentation rate (ESR) is inversely correlated with the proportion of CD57+ T cells in the joint fluid. Although RA frequently occurs in patients with CD3+57+ cell leukaemia, and some CD57+ T cells are likely to be involved in the onset of RA, we suggest that CD57+ T cells may rather suppress inflammation of RA, and other cellular components (e.g. granulocytes) may govern the severity of the inflammation of RA. These CD57+ T cells are probably generated extrathymically in the adjacent BM or joint space.     

Incidence of progressive supranuclear palsy and multiple system atrophy in Olmsted County, Minnesota, 1976 to 1990

Information on the incidence of progressive supranuclear palsy (PSP) is limited; incidence rates for multiple system atrophy (MSA) are not available. We studied the incidence of PSP and MSA in Olmsted County, Minnesota, for the years 1976 to 1990. This study was part of a larger investigation of all forms of parkinsonism. We used the medical records-linkage system of the Rochester Epidemiology Project to identify all subjects whose records contained documentation of any from of parkinsonism, related neurodegenerative diseases, or tremor of any type. A nurse abstractor screened the records and, when applicable, a neurologist reviewed them to determine the presence or absence of parkinsonism. Cases of parkinsonism were classified using specified diagnostic criteria. Population denominators were derived from census data and were corrected by removing prevalent cases of parkinsonism. Over the 15 years of the study, we found 16 incident cases of PSP and nine incident cases of MSA. No cases of PSP or MSA had onset before age 50 years. The average annual incidence rate (new cases per 100,000 person-years) for ages 50 to 99 years was 5.3 for PSP and 3.0 for MSA. The incidence of PSP increased steeply with age from 1.7 at 50 to 59 years to 14.7 at 80 to 99 years, and was consistently higher in men. Median survival time from symptom onset was 5.3 years for PSP and 8.5 years for MSA. The incidence of PSP increases with age and is consistently higher in men at all ages. PSP and MSA are more common than previously recognized.     

A population study of the natural history of Wolff-Parkinson-White syndrome in Olmsted County, Minnesota, 1953-1989

BACKGROUND: Virtually all natural history studies of Wolff-Parkinson-White (WPW) syndrome have been case series and, as such, have been constrained by referral biases, skewed age and sex distributions, or brief follow-up periods. The purpose of our study was to examine the natural history, the development of arrhythmias, and the incidence of sudden death in an entire cohort of pediatric and adult WPW patients from a community-based local population. METHODS AND RESULTS: We identified 113 residents of Olmsted County, Minnesota, during the period 1953-1989 using the centralized records-linkage system provided by the Mayo Clinic and the Rochester Epidemiology Program Project. Medical records and ECGs were reviewed to confirm the diagnosis and to establish pathway location by ECG criteria. Follow-up, via record review and telephone interview, was complete in 95% of subjects through 1990. The incidence of newly diagnosed cases was approximately four per 100,000 per year. Preexcitation was not present on the initial ECG of 22% of the cohort. Approximately 50% of the population was asymptomatic at diagnosis, with 30% subsequently having symptoms related to arrhythmia at follow-up. Two sudden cardiac deaths (SCD) occurred over 1,338 patient-years of follow-up, yielding an overall SCD rate of 0.0015 (95% confidence interval, 0.0002-0.0054) per patient-year. No SCD occurred in patients asymptomatic at diagnosis. CONCLUSIONS: The incidence of sudden death in a local community-based population is low and suggests that electrophysiological testing should not be performed routinely in asymptomatic patients with WPW syndrome. Nevertheless, young, asymptomatic patients, particularly those < 40 years old, should return for medical follow-up should symptoms develop.     

The enigma of giant cell arteritis: multidisciplinary management of two cases

BACKGROUND: Giant cell arteritis is an enigmatic disease that is characterized by chronic granulomatous inflammation of the walls of large and medium-sized arteries. The process has a predilection for the extradural cranial arteries, which include the ophthalmic and the posterior ciliary arteries. A multisymptom disease of older individuals, giant cell arteritis often manifests challenging issues and diagnostic dilemmas. CASE REPORTS: We illustrate two cases with initial symptoms of intermittent headache, malaise, and decreased visual acuity that were incorrectly diagnosed or ultimately misdiagnosed. The first case represents a patient who was diagnosed as having migraine headache and an erythrocyte sedimentation rate (ESR) that was interpreted by the attending physician as too low to warrant temporal artery biopsy. The second case is that of a patient who had a history of headaches, jaw claudication, and numerous medical evaluations. CONCLUSION: Giant cell arteries is an enigmatic disease with multiple manifestations. The differential diagnoses can range from temporal mandibular joint dysfunction to tension headache. Imminent vision loss as a sequelae of this condition warrants careful review of ocular and constitutional history and prompt treatment.     

Health care utilization in multiple sclerosis: a population-based study in Olmsted County, MN

OBJECTIVE: The authors sought to determine acute ambulatory- and hospital-billed charges for the Olmsted County, Minnesota Multiple Sclerosis (MS) Disability Prevalence Cohort and compare them to those incurred by the general population. METHODS: Billed charges for 155 people with clinically definite or laboratory-supported MS were compared with those of age- and gender-matched non-MS controls. Billing data, including all inpatient and outpatient acute and rehabilitative medical care charges over a 5-year period surrounding a December 1, 1991 prevalence date, were analyzed. Data were correlated with level of disability using the Minimal Record of Disability for MS. RESULTS: Median total annual billed charges for most individuals with MS, including those with less severe ($1,277) and relapsing-remitting illness ($1,348), did not differ from those for controls ($1,327, p=0.075). Only those with severe MS (22.6%) had median annual medical charges higher than controls ($5,440, p < 0.001). Male patients with MS had higher median annual total charges ($2,353) than male controls ($762, p=0.003). Total charges for female patients with MS ($1,440) were not different from those for female controls ($1469). Median annual outpatient charges were 15% more for the MS group ($1,418) than for controls ($1,231). Patients with MS had a mean of 0.2 hospital admissions annually compared with 0.1 annual admissions per control patient. Among variables collected on persons with MS, the Expanded Disability Status Scale was the strongest predictor of level of charges (p < 0.001). CONCLUSION: Acute ambulatory- and hospital-billed charges for most patients with MS do not differ from those of the general population.     

Elastase derived elastin peptides: putative autoimmune targets in giant cell arteritis

OBJECTIVE: Histological analysis of giant cell arteritis (GCA) reveals a granulomatous reaction around the internal elastic lamina. Elastolysis by multinucleated giant cells has also been reported. We investigated elastin derived peptides as putative recall antigens for peripheral blood mononuclear cells (PBMC) from patients with GCA. METHODS: PBMC were collected from 17 patients with GCA (Group 1), 17 patients with vascular diseases, connective tissue diseases, or polymyalgia rheumatica without GCA (Group 2), and 17 healthy controls (Group 3). Cultures of PBMC with different elastin derived peptides or elastase were analyzed. RESULTS: A proliferative response was obtained only with elastate derived elastin peptides in 12/13 untreated patients with GCA. Steroid treatment was believed to abolish this proliferative response in 4 patients with GCA. PBMC from only 3/34 non-GCA subjects responded to these antigens. No proliferative response was obtained for other elastin derived peptides or elastase in any subject. CONCLUSION: Degradation of native elastin by leukocyte elastase can provide elastin derived peptides that act as autoimmune targets for T cells in GCA.     

Primary lung neoplasm of rare incidence: giant cell carcinoma

Primary giant-cell carcinoma of the lung is an infrequent observation. It is distinguished clinically solely its fairly rapid development but otherwise it does not seem to have any predilection for localization, age or sex. Histologically, differential diagnosis with othe tumours such as angiosarcoma, rhabdomyosarcoma, chorioepithelioma and others is of interest. Three cases of primary giant-cell carcinoma of the lung are reported and the various clinical and anatomopathological aspects discussed.