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W A Rocca

Publications and source records attributed to W A Rocca.

At least 55 records · Page 3Linked to original sources

Stroke incidence and survival in three Sicilian municipalities. Sicilian Neuro-Epidemiologic Study (SNES) Group.

We investigated the incidence of first-ever stroke in three Sicilian municipalities over the years 1984-1987. Case ascertainment involved two approaches: a door-to-door two-phase prevalence survey and a study of death certificates. Only first-ever strokes occurring within the study time interval were included, and diagnoses were based on specified criteria. We found 138 subjects who had experienced a first stroke over 73 488 person-years; the average incidence rate (new cases per 1000 population per year) was 1.9 overall, 1.7 in men, and 2.1 in women. Incidence increased steeply with age and was similar in men and women. Incidence was similar in the three study municipalities. The overall case-fatality rate was 35% at 30 days and 22% at one week. Survival after stroke was similar in men and women but better in younger compared to older stroke patients. Comparisons with previous studies suggest the absence of major geographic variations in stroke incidence within Italy.

Adult↗

Validation of a telephone questionnaire for Parkinson's disease.

As part of a genetic study, we investigated the accuracy of a telephone questionnaire to diagnose or screen for Parkinson's disease (PD). We studied 20 PD patients randomly selected among all incident cases in Olmsted County, Minnesota, for the period 1970 through 1988. Each patient was matched by age and sex to a subject free of PD or parkinsonism residing in the same county. In addition, we studied 20 patients with PD referred to our institution from outside of Olmsted County between 1991 and 1993. Medical record documentation of disease status for both affected and unaffected subjects served as the standard for comparison. A trained interviewer kept unaware of disease status administered nine symptom questions via telephone to all study subjects (or their proxy). Seventeen PD cases from Olmsted County, all 20 referral cases, and 16 unaffected subjects participated in the interview (total = 37 with PD and 16 unaffected subjects); 36 interviews (24 PD) were with a proxy and 17 (13 PD) were direct. Questions regarding "poor balance," "trouble buttoning," and "trouble arising" had the highest sensitivity; questions regarding "shaking," "feet stuck to the floor," "softer voice," and "smaller writing" had the highest specificity. A combination of any four symptoms yielded the best balance between sensitivity (89%) and specificity (88%). Although the questionnaire appears to be useful both as a screening and as a diagnostic tool, it failed to reach complete accuracy, and it should be used in the context of a more complex case-finding strategy.

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Pitfalls in neuroepidemiologic research.

In neuroepidemiologic research, there are many pitfalls to trap unwary investigators, whether the project is a survey, a case-control study, or some other type of study. We briefly discuss pitfalls relating to: research preliminaries (e.g., failure to decide on study objectives); personnel and training (e.g., deficient training); data collection (e.g., ineffective supervision); data ownership and data sharing (disagreement about how the data will be used), and report preparation (e.g., failure to interpret results in the context of uncertainties arising from the design and implementation of the research). Awareness of these pitfalls will reduce the likelihood of flawed or ineffective neuroepidemiologic research.

Data Collection↗

Drug-induced parkinsonism as a risk factor for Parkinson's disease: a historical cohort study in Olmsted County, Minnesota.

OBJECTIVE: To investigate whether subjects who experienced a reversible episode of drug-induced parkinsonism have an increased risk of subsequent Parkinson's disease. DESIGN: We undertook a historical cohort study based on the medical records-linkage system of the Rochester Epidemiology Project in Olmsted County, Minnesota. MATERIAL AND METHODS: All subjects in whom drug-induced parkinsonism developed between 1955 and 1990 and was indexed in the medical records-linkage system were identified. In the 24 eligible subjects, follow-up for the subsequent development of Parkinson's disease consisted of a total of 192.7 person-years. The observed number of cases of Parkinson's disease was compared with the expected number of cases in an age- and sex-matched cohort from the general population. RESULTS: In 2 of 24 subjects with drug-induced parkinsonism, Parkinson's disease later developed. A comparison with the expected number of cases in the general population (0.08) yielded a relative risk of 24.3 (95% confidence interval, 2.9 to 87.5; P = 0.006). CONCLUSION: Our findings suggest that drug-induced parkinsonism is associated with an increased risk of Parkinson's disease. Clarification of the mechanisms of this association may have preventive implications.

Adult↗

Risk of dementia among persons with diabetes mellitus: a population-based cohort study.

It is unclear whether persons with diabetes are at increased risk for dementia, including Alzheimer's disease. Existing studies are limited by small sample size, selection bias, and case-control designs. This population-based historical cohort study provides estimates of the risk of dementia and Alzheimer's disease associated with adult onset diabetes mellitus (AODM). The sample included all persons with AODM residing in Rochester, Minnesota, on January 1, 1970, plus all persons diagnosed in Rochester or who moved to Rochester with the diagnosis between January 1, 1970, and December 31, 1984. Individuals were followed through review of their complete medical records from AODM diagnosis until dementia onset, emigration, death, or January 1, 1985. Standardized morbidity ratios for dementia and Alzheimer's disease were calculated, using an expected incidence based on age- and sex-specific rates for the Rochester population. Poisson regression was used to estimate risks for persons with AODM relative to those without. Of the 1,455 cases of AODM followed for 9,981 person-years, 101 developed dementia, including 77 who met criteria for Alzheimer's disease. Persons with AODM exhibited significantly increased risk of all dementia (Poisson regression relative risk (RR) = 1.66, 95% confidence interval (CI) 1.34-2.05). Risk of Alzheimer's disease was also elevated (for men, R = 2.27, 95% CI 1.55-3.31; for women, RR = 1.37, 95% CI 0.94-2.01). These findings emphasize the importance of AODM prevention and prompt additional investigation of the relation between AODM and dementia.

Age Distribution↗

Prevalence of Parkinson's disease in Junín, Buenos Aires Province, Argentina.

We investigated the prevalence of Parkinson's disease (PD) in a South American city: Junín, Buenos Aires Province, Argentina. At dwellings systematically selected, the case finding involved household screenings and neurological examinations (i.e., a two-phase survey approach). Only persons 40 years of age or older were eligible (N = 7,765). There were 51 cases of PD identified, yielding a crude prevalence of 656.8 per 100,000 population. The age-specific prevalence was consistently higher in men than women, and it increased with advancing age for both sexes. In addition to prevalence figures. we present tallies related to clinical features of PD, as well as tallies related to other subtypes of parkinsonism.

Adult↗

Prevalence of parkinsonism and Parkinson's disease in Europe: the EUROPARKINSON Collaborative Study. European Community Concerted Action on the Epidemiology of Parkinson's disease.

OBJECTIVES: To assess and compare the prevalence of parkinsonism and Parkinson's disease in five European populations that were surveyed with similar methodology and diagnostic criteria. METHODS: Joint analysis of five community surveys--Gironde (France), eight centres in Italy, Rotterdam (The Netherlands), Girona (Spain), and Pamplona (Spain)--in which subjects were screened in person for parkinsonism. Overall, these surveys comprised 14,636 participants aged 65 years or older. RESULTS: The overall prevalence (per 100 population), age adjusted to the 1991 European standard population, was 2.3 for parkinsonism and 1.6 for Parkinson's disease. The overall prevalence of parkinsonism for the age groups 65 to 69, 70 to 74, 75 to 79, 80 to 84, and 85 to 89 years was respectively, 0.9, 1.5, 3.7, 5.0, and 5.1. The corresponding age specific figures for Parkinson's disease were 0.6, 1.0, 2.7, 3.6, and 3.5. After adjusting for age and sex, the prevalence figures did not differ significantly across studies, except for the French study in which prevalence was lower. Prevalence was similar in men and women. Overall, 24% of the subjects with Parkinson's disease were newly detected through the surveys. CONCLUSIONS: Prevalence of both parkinsonism and Parkinson's disease increased with age, without significant differences between men and women. There was no convincing evidence for differences in prevalence across European countries. A substantial proportion of patients with Parkinson's disease went undetected in the general population.

Age Distribution↗

A population perspective on diagnostic criteria for Parkinson's disease.

For Parkinson's disease (PD), little is known about how the choice of diagnostic criteria affects research results. Using data on PD from three community studies (from Argentina, the Netherlands, Italy), we compared the impact on prevalence of several sets of diagnostic criteria. Each set was based on cardinal signs--resting tremor, bradykinesia, rigidity, impaired postural reflexes--and required that other parkinsonism be excluded. Some sets had additional requirements related to duration of symptoms, asymmetry of signs, or response to medication. In terms of prevalence, much lower estimates were associated with the requirements of asymmetry of signs and response to medication. The assessment of these clinical features may not be practical in community studies. Impaired postural reflexes, as a cardinal sign, seemed superfluous. For community studies of PD, we recommend the following diagnostic criteria: at least two of resting tremor, bradykinesia, or rigidity, in the absence of other apparent causes of parkinsonism.

Age Distribution↗

Smoking and Parkinson's disease. An age-dependent risk effect? The EUROPARKINSON Study Group.

We studied the association between smoking and Parkinson's disease (PD) through a case-control study. Several studies have shown an inverse association between smoking and PD. This association has been interpreted as spurious by some investigators, and as real and causal by others. Several other studies did not confirm the inverse association. We included 193 prevalent cases of PD ascertained in five European prevalence surveys that followed a two-phase design of screening and clinical examination. Each case was matched by center, age (+/- 2 years), and gender to three control subjects drawn from the same populations (N = 579). Information on smoking was obtained through direct or proxy interview. Overall, there was no association between ever smoking and PD (odds ratio = 1.1; p = 0.6). Analyses stratified by age showed that ever smoking was associated with a decreased risk of PD in the younger individuals (odds ratio = 0.4; p = 0.03) and with a significant trend of increasing risk with advancing age (p = 0.003). The risk of PD in relation to smoking is strongly modified by age; smoking may be protective in the younger cases but not in the older cases. This finding may explain the conflicting results from previous studies.

Adult↗

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.

Adolescent↗

Occupation, education, and Parkinson's disease: a case-control study in an Italian population.

Current epidemiologic data on the association between occupational exposures and Parkinson's disease (PD) are inconsistent. In a case-control study, we investigated the associations between occupation and PD and between education and PD. The cases (n = 62) were those identified in a prevalence survey (door-to-door, two-phase) of three Sicilian municipalities, as a November 1, 1987. We then randomly selected from the general population two controls for each case, matched for age ( +/- year), sex, and municipality (n = 124). Information on current and past occupations and education for cases and controls was obtained during the survey. Subjects who worked for most of their lives as farmers were not at increased risk of PD (OR = 0.6; 95% CI = 0.3-1.3). Neither were subjects who worked for most of their lives in other occupations (e.g., housewives, fishermen, factory workers, salesmen, craftsmen, clerks). PD was not associated with low education. Our findings suggest that farming, as a broad occupational category, does not play a major role in the causation of PD.

Adult↗

Impact of referral bias on clinical and epidemiological studies of Alzheimer's disease.

We used the resources of the Rochester Epidemiology Project to compare sociodemographic and clinical characteristics in three groups of Alzheimer's disease patients. The first group included incidence cases occurring among residents of Rochester, Minnesota (population-based series; n = 241). The second group was a sample of patients referred to the Mayo Clinic form the remainder of Minnesota and the four surrounding states (n = 58); the third was a sample referred from the remainder of the United States (n = 94). Patients from Rochester were more frequently women, less highly educated, less commonly white collar workers, more frequently institutionalized, less frequently married, and more often lived along than those in the two referral groups. Patients from Rochester also had a more advanced age of onset of dementia. For occupation, education, and living arrangement, the differences across groups increased with increasing distance of referral. Clinical and epidemiological studies based on patients referred form primary to secondary or tertiary care centers may suffer from severe selection bias.

Adult↗

Severe, uncontrolled hypertension and adult-onset seizures: a case-control study in Rochester, Minnesota.

PURPOSE: Hypertension is an established risk factor for clinically detected stroke, which is in turn a risk factor for epilepsy. This relation suggested that hypertension, particularly severe and uncontrolled, might increase the risk of epilepsy in the absence of prior clinically detected stroke. METHODS: Subjects in this population-based case-control study were the 145 incident cases of first unprovoked seizure aged 55 years or older and 290 controls matched to cases on age, gender, and duration of medical follow-up. Using the records-linkage system of the Rochester Epidemiology Project, we obtained, for both cases and matched controls, all blood pressure readings before each case's first seizure came to medical attention. Subjects were classified as hypertensive if they had at least two readings of > or = 160/95 mm Hg or if there was electrocardiographic evidence for left ventricular hypertrophy. RESULTS: Severe uncontrolled hypertension increased the risk of unprovoked seizure. Left ventricular hypertrophy without diuretic treatment was associated with an 11-fold increased risk of unprovoked seizure: left ventricular hypertrophy treated with diuretics did not increase the risk. CONCLUSIONS: In the absence of clinically detected stroke, left ventricular hypertrophy without diuretic use may increase the risk of unprovoked seizures, and diuretic treatment may protect against this increased risk.

Adolescent↗

Prevalence of lumbosacral radiculopathy in two Sicilian municipalities. Sicilian Neuro-Epidemiologic Study (SNES) Group.

OBJECTIVES: As part of a door-to-door survey of neurologic diseases, we investigated the prevalence of lumbosacral radiculopathy (LR) in two Sicilian municipalities (N = 14,540, as of November 1, 1987). MATERIAL & METHODS: During phase 1, we administered a brief screening instrument to subjects in the study population. In phase 2, study neurologists using specified diagnostic criteria investigated those subjects who screened positive. Our case finding was restricted to subjects who manifested symptoms of LR in the six months preceding the prevalence day. RESULTS: We found 143 subjects affected by LR (112 definite, 31 possible) yielding a crude prevalence of 9.8 cases per 1,000 population. Age-specific prevalence was generally higher in men; it increased to a peak at age 50-59 years and decreased steadily thereafter. At the peak, prevalence was higher in factory workers, housewives, and clerks compared to workers in other occupations. CONCLUSIONS: LR is a common neurologic disease in the general population.

Adult↗

Incidence and lifetime prevalence of Bell's palsy in two Sicilian municipalities. Sicilian Neuro-Epidemiologic Study (SNES) Group.

INTRODUCTION: In a door-to-door two-phase survey of common neurologic diseases conducted in two Sicilian municipalities, we investigated the incidence and the lifetime prevalence of Bell's palsy (BP). MATERIAL & METHODS: During phase I, we administered a screening instrument for facial palsy to 11,901 adult persons. During phase 2, study neurologists using specified diagnostic criteria evaluated those subjects who screened positive. RESULTS: We found 73 subjects who had experienced BP during their life. The lifetime prevalence as of November 1, 1987, was 642.8 cases per 100,000 population age 15 years and above. The prevalence increased with age and was similar in men and women. Eighteen episodes of BP occurred in the three years preceding the prevalence day. The average annual incidence rate was 52.8 new episodes per 100,000 population age 15 years and above. Incidence increased with age. CONCLUSION: Comparison with other incidence studies suggests some geographic variability.

Adolescent↗

Prevalence of stroke: a door-to-door survey in three Sicilian municipalities. Sicilian Neuroepidemiologic Study (SNES) Group.

As part of a door-to-door survey, we screened for stroke among the inhabitants of three Sicilian municipalities (n = 24,496 as of November 1, 1987). Neurologists then investigated those subjects suspected to have had a stroke. Diagnoses of first-ever strokes were based on specified criteria and were reviewed by an adjudication panel. We found 189 subjects who had experienced at least one completed stroke (180 definite, 9 possible); 15 strokes were hemorrhagic, 71 ischemic, and 103 uncertain. The prevalence (cases/100,000) was 771.6 in the total population and 1,893.6 in those aged 40 years or over. The prevalence increased steeply with age, was higher in men between 60 and 79 years, but was higher in women thereafter. Age-specific figures were similar in the three study municipalities. Although all first-ever strokes had been previously diagnosed, 40% of the subjects had not been hospitalized for this condition.

Adult↗