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Biomedical subjects

W A Rocca

Publications and source records attributed to W A Rocca.

At least 37 records · Page 2Linked to original sources
PubMed2000

Incidence of medically recognized migraine: A 1989-1990 study in Olmsted County, Minnesota.

OBJECTIVE: To investigate the incidence of medically recognized migraine in Olmsted County, Minnesota, during the years 1989 to 1990. METHODS: We used the records-linkage system of the Rochester Epidemiology Project to identify all subjects who sought medical attention for their headache and had their initial visit for migraine within the study period. Incident cases were classified using specified criteria. RESULTS: From 9837 records screened, we found 713 incident cases. The average annual incidence rate (new cases per 100 000 person-years) was 343.0 in both sexes combined, 481.6 in women, and 194.4 in men. In women, incidence rates were low at the extremes of age and higher among those aged between 10 and 49 years, with a striking peak at the age of 20 to 29 years. Migraine without aura was the most common type of migraine in women. Men had a more constant risk of migraine throughout life with a lesser peak at the age of 10 to 19 years, and they were equally affected by all types of migraine. Women had consistently higher incidence rates than men at all ages, and there were strikingly higher incidence rates of migraine without aura in women than in men. CONCLUSIONS: Although our incidence rates were restricted to medically recognized cases of migraine, we confirmed previously reported epidemiological patterns.

Adolescent↗
PubMed2000

The cost of epilepsy in the United States: an estimate from population-based clinical and survey data.

PURPOSE: To provide 1995 estimates of the lifetime and annual cost of epilepsy in the United States using data from patients with epilepsy, and adjusting for the effects of comorbidities and socioeconomic conditions. METHODS: Direct treatment-related costs of epilepsy from onset through 6 years were derived from billing and medical chart data for 608 population-based incident cases at two sites in different regions of the country. Indirect productivity-related costs were derived from a survey of 1,168 adult patients visiting regional treatment centers. Direct costs separate the effects of epilepsy and comorbidity conditions. Indirect costs account for the effects of other disabilities and socioeconomic conditions on foregone earnings and household activity. The estimates were applied to 1995 population figures to derive national projections of the lifetime and annual costs of the disorder. RESULTS: The lifetime cost of epilepsy for an estimated 181,000 people with onset in 1995 is projected at $11.1 billion, and the annual cost for the estimated 2.3 million prevalent cases is estimated at $12.5 billion. Indirect costs account for 85% of the total and, with direct costs, are concentrated in people with intractable epilepsy. CONCLUSIONS: Direct costs attributable to epilepsy are below previous estimates. Indirect costs adjusted for the socioeconomic conditions of patients are above previous estimates. Findings indicate that epilepsy is unique in the large proportion of costs that are productivity-related, justifying further investment in the development of effective interventions.

Adult↗
PubMed1999

Case-control study of the ubiquitin carboxy-terminal hydrolase L1 gene in Parkinson's disease.

We investigated the association of PD with a recently reported I93M mutation of the ubiquitin carboxy-terminal hydrolase L1 (UCH-L1) gene, and with a new and common polymorphic variant S18Y of the same gene. We did not identify the I93M mutation in any of 139 unrelated PD cases or 113 controls. However, S18Y polymorphism carriers had significantly lower risk of PD (odds ratio = 0.53; p = 0.03), and the risk reduction was greater for younger onset cases.

Adult↗
PubMed1999

Increasing incidence of medically recognized migraine headache in a United States population.

OBJECTIVE: To investigate trends in the incidence of medically recognized migraine in Olmsted County, Minnesota over approximately a decade. METHODS: The authors used the records-linkage system of the Rochester Epidemiology Project to identify individuals whose records included any diagnostic rubric related to headache for the 3-year period 1979 through 1981 and the 2-year period 1989 through 1990. A nurse abstracter and a neurologist (J.W.S.) reviewed the complete history of each potential case and assigned a diagnosis using the International Headache Society classification (IHS, modified). Only patients who consulted a doctor for their headache and had their initial visit for migraine within the study years were considered as incident cases. RESULTS: The incidence of medically recognized migraine increased in female subjects between the 1979-through-1981 period and the 1989-through-1990 period for all ages, but particularly among those who were aged 10 to 49 years. The peak incidence rate at age 20 to 29 years increased from 634.5 new cases per 100,000 person-years in 1979 through 1981 to 986.4 in the 1989-through-1990 period (absolute increase 351.9; relative increase 56%). The rise in incidence in female subjects was most sizable for migrainous disorder (IHS code 1.7); smaller increases were noted for migraine without aura and with typical aura. Only a slight absolute increase in migraine incidence rates was observed in male subjects, restricted to those 10 to 19 years of age (absolute increase 174.7; relative increase 89%). CONCLUSIONS: Although the incidence rates reported here are restricted to patients who consulted a doctor for their headache, the authors suggest that the incidence of migraine has increased over time in female subjects, especially those of reproductive age. The increase was most pronounced for migrainous disorder. Incidence rates were more stable in male subjects over time.

Adolescent↗
PubMed1999

Autopsy patterns for Parkinson's disease and related disorders in Olmsted County, Minnesota.

Using a records-linkage system, we determined the frequency and distribution of brain autopsies in residents of Olmsted County, Minnesota, in whom parkinsonism developed during 1976 through 1990. Of the 364 incident cases identified, 235 patients were deceased at the time of record abstraction. The overall autopsy rate was low (23%). Diagnostic certainty (for PD), diagnostic type (PD versus other parkinsonism), sex, age at death, and location at death were important selection factors for autopsy.

Autopsy↗
PubMed1999

Familial aggregation of Parkinson's disease: a population-based case-control study in Europe. EUROPARKINSON Study Group.

OBJECTIVE: To investigate the familial aggregation of PD in a large collaborative population-based case-control study. BACKGROUND: Most previous case-control studies of the familial aggregation of PD have been hospital- or clinic-based. METHODS: We included 219 prevalent cases ascertained in three European populations (centers), using a two-phase design consisting of screening and examination by a neurologist. Each case was matched by age, sex, and center to three controls drawn from the same populations (n = 657). Presence of PD among first-degree relatives (parents and siblings) was determined using the family history approach for 175 cases and 481 controls. RESULTS: Overall, a positive family history (at least one parent or sibling affected by PD) was reported in 10.3% of patients and 3.5% of controls (odds ratio [OR] = 3.2; 95% confidence interval [CI] = 1.6 to 6.6). A similar association was observed when analyses were restricted to nondemented patients and controls (OR = 3.9; 95% CI = 1.7 to 8.7) or to newly diagnosed patients (OR = 3.3; 95% CI = 0.9 to 11.9). We found a significant trend of increasing risk with increasing number of affected relatives (p = 0.003). Analyses stratified by age showed a stronger association for younger PD patients (OR = 7.6; 95% CI = 1.5 to 38.9) than for older patients (OR = 2.5; 95% CI = 1.1 to 5.7). CONCLUSIONS: In this large sample of prevalent PD patients and population-matched controls, PD significantly aggregates in families, with the strength of the association being age-dependent. Therefore, familial factors, which can be genetic, environmental, or both, play a role in PD.

Aged↗
PubMed1999

Incidence and distribution of parkinsonism in Olmsted County, Minnesota, 1976-1990.

OBJECTIVE: Limited information is available on the frequency and distribution of parkinsonism as a syndrome. We studied the incidence of parkinsonism and its specific types among residents of Olmsted County, MN, for the period from 1976 through 1990. METHODS: We used the medical records linkage-system of the Rochester Epidemiology Project to identify all individuals whose records contained documentation of any form 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 of parkinsonism using specified diagnostic criteria and to define the year of onset. RESULTS: We found 364 incident cases of parkinsonism: 154 with PD (42%), 72 with drug-induced parkinsonism (20%), 61 unspecified (17%), 51 with parkinsonism in dementia (14%), and 26 with other causes (7%). The average annual incidence rate of parkinsonism (per 100,000 person-years) in the age group 50 to 99 years was 114.7; incidence increased steeply with age from 0.8 in the age group 0 to 29 years to 304.8 in the age group 80 to 99 years. The cumulative incidence of parkinsonism assuming no competing causes of death was 7.5% to age 90 years. PD was the most common type of parkinsonism, followed by parkinsonism in dementia in men and drug-induced parkinsonism in women. Men had higher incidence than women at all ages for all types of parkinsonism except drug-induced. CONCLUSIONS: Parkinsonism is a common disease among the elderly; its incidence increases steeply with advancing age and is consistently higher in men. The distribution by type changes with age and gender.

Age Distribution↗
PubMed1999

Postmenopausal estrogen replacement therapy and risk of AD: a population-based study.

OBJECTIVE: To study the association between estrogen replacement therapy in postmenopausal women and AD using a case-control design. BACKGROUND: Studies of the effect of estrogen therapy on the risk of AD have been limited and have yielded conflicting results. METHODS: Case patients were all postmenopausal women who developed AD in the quinquennium 1980 through 1984 in Rochester, MN (n = 222). One control subject from the same population and free of dementia was matched to each case patient by age (+/-3 years) and length of enrollment in the records-linkage system (n = 222). Estrogen exposure was defined as any form of estrogen (oral, parenteral, topical, suppository) used for at least 6 months after the onset of menopause and before the onset of AD (or corresponding year in the matched control subject). Information on dose and duration of use was abstracted. Consistent with the matched design, analyses entailed conditional logistic regression. RESULTS: AD patients and control subjects had identical age at menarche (median: 13.0 versus 13.0 years) and age at menopause (median: 50.0 versus 50.0 years). The frequency of estrogen use was higher among control subjects than AD patients (10% versus 5%; odds ratio = 0.42; 95% confidence interval 0.18 to 0.96; p = 0.04). There was a significant trend of decreasing odds ratios with increasing duration of use. The inverse association between estrogen therapy and AD remained significant after adjustment for education and age at menopause. CONCLUSION: These results from a population-based study suggest that estrogen replacement therapy is associated with a reduced risk of AD in postmenopausal women.

Adult↗
PubMed1999

Incidence of epileptic syndromes in Rochester, Minnesota: 1980-1984.

PURPOSE: To determine the incidence and the distribution of epileptic syndromes in a well-defined population. METHODS: By using the records-linkage system of the Rochester Epidemiology Project, we screened all the residents of Rochester, Minnesota, who received a diagnosis of seizures, convulsions, or epilepsy from 1980 through 1984. One hundred fifty-seven residents with incident epilepsy (recurrent unprovoked seizures) were classified by using the International League Against Epilepsy (ILAE) Classification of the Epilepsies and Epileptic Syndromes. Residents with special syndromes were excluded. With a pretested algorithm, patients were classified at three levels of specification: major syndromic groups (e.g., localization-related syndromes), syndromic subgroups (e.g., idiopathic epilepsy with age-related onset), and whenever possible, individual syndromes. RESULTS: All but one patient were classified into major syndromic groups and subgroups. The annual age-adjusted incidence per 100,000 population was 52.3 cases (34.9 for localization-related epilepsies; 7.7 for generalized epilepsies; 9.7 for undetermined epilepsies). Incidence was 0.2 for idiopathic, 17.2 for cryptogenic, 17.5 for symptomatic localization-related epilepsies, 3.7 for idiopathic, 1.7 for symptomatic or cryptogenic (age-related), and 2.3 for symptomatic (non age-related) generalized epilepsies. CONCLUSIONS: With the exception of idiopathic epilepsies, the incidence of the major syndromic categories in our study was higher than that provided by previous population-based studies.

Adolescent↗
PubMed1999

Prevalence of dementia in the rural village of Hanazono-mura, Japan.

We studied the prevalence of dementing disorders in a rural municipality of Japan (Hanazono-mura), using a door-to-door two-phase design. In phase 1, the Hasegawa's Dementia Scale-Revised was applied as a screening test to all subjects aged 65 years and older (n = 201). Among subjects screened positive, 17 were diagnosed with dementia in phase 2. The prevalence (cases/100 aged 65 years and older) was 8.5 for all types of dementia, 3.5 for Alzheimer's disease, 3.0 for vascular dementia, and 2.0 for other dementia (including mixed dementia). The prevalence of dementia was slightly but consistently higher in men than women at all ages. The overall prevalence was higher in women for Alzheimer's disease and in men for vascular dementia.

Aged↗
PubMed1999

The incidence and prevalence of myoclonus in Olmsted County, Minnesota.

OBJECTIVE: To study the incidence and prevalence of diagnosed myoclonus in Olmsted County, Minnesota. Little is known about the frequency and distribution of myoclonus in the general population. DESIGN: Descriptive study with case ascertainment through a records-linkage system. PATIENTS AND METHODS: We used a medical records-linkage system to identify all subjects whose records contained documentation of myoclonus or of diseases known to exhibit myoclonus. The records of all potential patients were reviewed by a neurologist, and only patients with pathologic and persistent myoclonus were included. Population denominators were derived from census data. RESULTS: The average annual incidence rate of pathologic and persistent myoclonus for 1976 through 1990 was 1.3 cases per 100,000 person-years. The rate increased with advancing age and was consistently higher in men. Symptomatic myoclonus was the most common type, followed by epileptic and essential myoclonus; dementing diseases were the most common cause of symptomatic myoclonus. The lifetime prevalence of myoclonus, as of January 1, 1990, was 8.6 cases per 100,000 population, and the prevalence increased with advancing age. CONCLUSION: Although our figures are probably under-estimated, they are the first attempt, to our knowledge, to measure myoclonus morbidity in the general population. We found clinical features and age and sex distributions different from those previously described in clinical series.

Adolescent↗
PubMed1999

Detection of preclinical Parkinson disease in at-risk family members with use of [123I]beta-CIT and SPECT: an exploratory study.

OBJECTIVE: To explore whether the radioligand 2 beta-carboxymethoxy-3 beta-(4-[123I] iodophenyl) tropane ([123I]beta-CIT) and single-photon emission computed tomography (SPECT) can detect decreased striatal uptake in at-risk relatives of patients with Parkinson disease (PD). PATIENTS AND METHODS: Ten PD patients, 10 at-risk first-degree relatives of PD patients, and 10 controls underwent [123I]beta-CIT and SPECT brain imaging. Their striatal uptake ratios were compared. RESULTS: Age-adjusted specific to nonspecific striatal uptake ratios were lower in patients compared with controls and with relatives; however, ratios were similar in relatives and controls. Among relatives, ratios were consistently lower in subgroups postulated to be at higher risk for preclinical PD. CONCLUSION: Our findings provide preliminary support that [123I]beta-CIT and SPECT may detect decreased striatal uptake in relatives of PD patients postulated to be at higher risk for PD.

Adult↗
PubMed1998

Incidence of dementia and Alzheimer's disease: a reanalysis of data from Rochester, Minnesota, 1975-1984.

For both dementia and Alzheimer's disease (AD), data regarding incidence rates in the oldest old and time trends in incidence are limited. The authors reanalyzed previously reported data on the incidence of dementia and AD in Rochester, Minnesota, from 1975 through 1984, using three new strategies. First, incidence rates were corrected by removing age-, sex-, and calendar year-specific prevalent cases from the census-derived denominator figures. Second, incidence figures for persons above age 84 years were disaggregated. Third, time trends were investigated graphically using age-specific curves and birth cohort curves. Dementia diagnosis and AD diagnosis followed defined ad hoc criteria. Analyses were conducted for men, women, and both sexes combined, and for dementia and AD separately. The age-specific incidence rates were similar in men and women, continued to increase after age 84 years, and remained stable over time for both dementia and AD. No birth cohort effect was present for either dementia or AD. The similar risks seen in men and women, the continuing increase in incidence after age 84 years, and the stability of incidence over time have important implications for etiologic research on AD.

Age Distribution↗
PubMed1998

Exclusion of genetic linkage to 4q21-23 and 17q21 in a family with Lewy body parkinsonism.

Genetic analysis of markers from chromosomes 4q21-23 and 17q21 in a family with apparently autosomal dominant Lewy body parkinsonism is presented. This analysis shows that the locus leading to this disease is not allelic with that previously shown to lead to Lewy body parkinsonism on chromosome 4 or to the locus on chromosome 17 leading to frontotemporal dementia with parkinsonism. A brief clinical comparison of this family with families showing linkage to these loci is presented. The data suggest that at least one other major genetic determinant for Lewy body parkinsonism remains to be identified.

Adult↗
PubMed1998

Risk factors for primary central nervous system lymphoma: a case-control study.

BACKGROUND: The incidence of primary central nervous system lymphoma (PCNSL) has increased over time in both immunocompetent and immunodeficient individuals. The reasons for the increase among immunocompetent patients are unclear. METHODS: The authors conducted a case-control study of PCNSL at the Mayo Clinic based on cases from local community and referral practices. Cases were all PCNSL patients without immunodeficiency diagnosed between 1975 and 1994 (n = 109). Two groups of controls were selected from the same referral practice, namely, patients with other cancer (cancer controls; n = 101), and patients with a different neurologic disease (neurologic controls; n = 109) seen at our institution during the same time period. RESULTS: PCNSL was significantly associated with lower education when cases were compared with cancer controls but only suggestively when cases were compared with neurologic controls. PCNSL cases were less likely to have had a history of tonsillectomy or oral contraceptive use compared with both control groups. The findings regarding autoimmune disorders and cardiovascular diseases were inconsistent for the two control groups. Neither farming nor prior personal or family history of cancer appeared to be risk factors for PCNSL. CONCLUSIONS: The findings of this study warrant further investigation of tonsillectomy and oral contraceptives as possible factors for PCNSL.

Adolescent↗
PubMed1998

A population-based study of seizures after traumatic brain injuries.

BACKGROUND: The risk of seizures is increased after traumatic brain injury, but the extent and duration of the increase in risk are unknown. The purpose of this study was to identify the characteristics of brain injuries that are associated with the development of seizures. METHODS: We identified 4541 children and adults with traumatic brain injury (characterized by loss of consciousness, post-traumatic amnesia, or skull fracture) in Olmsted County, Minnesota, during the period from 1935 through 1984. Injuries were classified as mild (loss of consciousness or amnesia lasting less than 30 minutes), moderate (loss of consciousness for 30 minutes to 24 hours or a skull fracture), or severe (loss of consciousness or amnesia for more than 24 hours, subdural hematoma, or brain contusion). We compared the incidence of new unprovoked seizures in this cohort with population rates, using standardized incidence ratios and Cox proportional-hazards analysis. RESULTS: The overall standardized incidence ratio was 3.1 (95 percent confidence interval, 2.5 to 3.8). The standardized incidence ratio was 1.5 (95 percent confidence interval, 1.0 to 2.2) after mild injuries but with no increase over the expected number after five years, 2.9 (95 percent confidence interval, 1.9 to 4.1) after moderate injuries, and 17.0 (95 percent confidence interval, 12.3 to 23.6) after severe injuries. In the multivariate analysis, significant risk factors for later seizures were brain contusion with subdural hematoma, skull fracture, loss of consciousness or amnesia for more than one day, and an age of 65 years or older. CONCLUSIONS: The increased risk of seizures after traumatic brain injury varies greatly according to the severity of the injury and the time since the injury.

Adolescent↗
PubMed1998

Case ascertainment uncertainties in prevalence surveys of Parkinson's disease.

Using unpublished data from five completed prevalence surveys of Parkinson's disease (PD), we investigated case ascertainment uncertainties that potentially have a direct effect on prevalence. These uncertainties arise from the choice of diagnostic criteria, the choice of screening method, and the amount of information lost because of nonresponse. The surveys were conducted in Argentina, India, China, Italy, and the Netherlands. Our analyses consisted of simple comparisons of prevalence results, positive predictive values (a screening measure), and nonresponse percentages. We found that (a) prevalence comparisons between surveys have diminished value if the surveys used different diagnostic criteria for PD; (b) screening performance may be affected adversely if symptom questions are answered by one family member for the entire family living together rather than by each family member individually; and (c) nonresponse from refusal or unavailability does not necessarily lead to bias, but special caution may be appropriate with prevalence results pertaining to elderly women.

Aged↗