Disability, support and long-term social care of an elderly Spanish population, 2008-2009: an epidemiologic analysis.

BACKGROUND: Though poorly known, relationships between disability, need of help (dependency) and use of social services are crucial aspects of public health. The objective of this study was to describe the links between disability, officially assessed dependency, and social service use by an industrial population, and identify areas of inequity. METHODS: We took advantage of a door-to-door survey conducted in the Cinco Villas district, Spain, in 2008-2009, which provided data on disability, morbidity, and service use among 1216 residents aged ≥50 years, and officially assessed dependency under the 2006 Dependency Act (OAD). Using logistic regression, we combined data collected at homes/residences on 625 disability screened-positive participants, and administrative information on degree of OAD and benefits at date of visit. RESULTS: Based on 163 disabled persons, the prevalence of residential/community-care users was 13.4% overall, with 6.0% being market-provided, 2.5% supported by the 2006 Act, and 4.9% supported by other public funds. Of 111 OAD applicants, 30 had been assigned an OAD degree; in 29 cases this was the highest OAD degree, with 12 receiving direct support for residential care and 17 receiving home care. Compared to unassessed dependency, the highest OAD degree was linked to residential care (OR and 95% CI) 12.13 (3.86-38.16), declared non-professional care 10.99 (1.28-94.53), and publicly-funded, non-professional care 26.30 (3.36-205.88). In contrast, 43 persons, 58% of the severely/extremely disabled, community-dwelling sample population, 81% of whom were homebound, including 10 persons with OAD but no implemented service plan, made no use of any service, and of these, 40% lacked a non-professional carer. CONCLUSIONS: Formal service use in the Cinco Villas district attained ratios observed for established welfare systems but the publicly-funded proportion was lower. The 2006 Act had a modest, albeit significant, impact on support for non-professional carers and residential care, coexisting with a high prevalence of non-use of social services by severely disabled persons.

Capture-recapture as a potentially useful procedure for assessing prevalence of multiple sclerosis: methodologic exercise using Portuguese data.

BACKGROUND: Capture-recapture methods (CRMs) are well established in epidemiologic surveillance and considered useful for the task of correcting for case-finding limitations in multiple sclerosis (MS) prevalence surveys. To date, however, CRMs have been exclusively applied to crude prevalence figures. This study therefore sought to explore an age-specific application of this method to an urban Portuguese population of 229,342. METHODS: We used a CRM to correct for the age-specific prevalence of MS obtained from two data sources, i.e. general practitioners in three primary-care districts and a neurology unit at the referral hospital. The corrected figures were adjusted for age using the European standard population as reference. RESULTS: When applied to 95 MS patients, the CRM impact was highest at ages 50-59 years, with a 110% increase in cases where the corrected prevalence was highest, i.e. 181.8 (95% CI 75.7-287.9) per 100,000, and lowest, nil, at ages ≥70 years, with an unchanged corrected prevalence of 13.8. The crude prevalence of 41.4 per 100,000 increased by 36% to 56.20 per 100,000 when it was CRM- and age-adjusted. Source independence was poor. CONCLUSIONS: CRMs can be differentially applied to MS counts. Valid comparisons may require simultaneous adjustment for age and other variables, such as diagnostic delay and diagnostic criteria. CRM applications to crude figures and dependent sources should be approached with caution.

Health professions and risk of sporadic Creutzfeldt-Jakob disease, 1965 to 2010.

In 2009, a pathologist with sporadic Creutzfeldt-Jakob Disease (sCJD) was reported to the Spanish registry. This case prompted a request for information on health-related occupation in sCJD cases from countries participating in the European Creutzfeldt Jakob Disease Surveillance network (EuroCJD). Responses from registries in 21 countries revealed that of 8,321 registered cases, 65 physicians or dentists, two of whom were pathologists, and another 137 healthcare workers had been identified with sCJD. Five countries reported 15 physicians and 68 other health professionals among 2,968 controls or non-cases, suggesting no relative excess of sCJD among healthcare professionals. A literature review revealed: (i) 12 case or small case-series reports of 66 health professionals with sCJD, and (ii) five analytical studies on health-related occupation and sCJD, where statistically significant findings were solely observed for persons working at physicians' offices (odds ratio: 4.6 (95 CI: 1.2-17.6)). We conclude that a wide spectrum of medical specialities and health professions are represented in sCJD cases and that the data analysed do not support any overall increased occupational risk for health professionals. Nevertheless, there may be a specific risk in some professions associated with direct contact with high human-infectivity tissue.

Incidence and prevalence of multiple sclerosis in Spain: a systematic review.

INTRODUCTION: Greater understanding of the prevalence and incidence of multiple sclerosis in Spain and their temporal trends is necessary to improve the allocation of healthcare resources and to study aetiological factors. METHODS: We performed a systematic search of the MedLine database and reviewed the reference lists of the articles gathered. We collected studies reporting prevalence or incidence rates of multiple sclerosis in any geographical location in Spain, with no time limits. In 70% of cases, data were extracted by 2 researchers (FGL and EAC); any discrepancies were resolved by consensus. RESULTS: We identified 51 prevalence and 33 incidence studies published between 1968 and 2018. In the adjusted analysis, the number of prevalent cases per 100 000 population increased by 26.6 (95% confidence interval [CI], 21.5-31.8) every 10 years. After adjusting for year and latitude, the number of incident cases per 100 000 population increased by 1.34 (95% CI, 0.98-1.69) every 10 years. We observed a trend toward higher prevalence and incidence rates at higher latitudes. CONCLUSIONS: The prevalence of multiple sclerosis in Spain has increased in recent decades, although case ascertainment appears to be incomplete in many studies. Incidence rates have also increased, but this may be due to recent improvements in the detection of new cases.

Prevalence and European comparison of dementia in a ≥75-year-old composite population in Spain.

OBJECTIVES: To estimate dementia prevalence in Spain. MATERIALS AND METHODS: Nine probabilistic and geographically defined samples participated. A screening design based on the MMSE was implemented. Positively screened individuals underwent clinical evaluation. The total number of cases in Spain was estimated. Prevalence was confronted to that of other European countries. RESULTS: Five hundred and forty-six persons aged ≥75 participated, 49 had dementia (35 with Alzheimer's disease [AD], 10 with vascular dementia [VD], 4 other; 25 first diagnosed in the study). Age- and sex-adjusted prevalence and estimated nationwide cases were 7.5% (95% CI 5.4-9.7), 5.6 (95% CI 3.7-7.5) and 1.4 (95% CI 0.5-2.3), and 290,000 (95% CI 208,000-372,000), 214,000 (95% CI 141,000-288,000) and 54,000 (95% CI 20,000-88,000) for dementia, AD and VD, respectively. CONCLUSIONS: Dementia prevalence in Spain is comparable to other European populations, while a high number of undiagnosed cases live in the community. The potential impact of Mediterranean diet, hypertension control and decreasing vascular risk factors is discussed.

Incidence of spinal cord injury worldwide: a systematic review.

BACKGROUND: Incidence studies of spinal cord injury (SCI) are important for health-care planning and epidemiological research. This review gives a quantitative update on SCI epidemiology worldwide through a statistical evaluation of incidence rates. METHODS: A systematic review was conducted. For each study, the crude rate ratio was calculated and, when possible, age- and gender-adjusted incidence rate ratios with 95% CI were determined by direct adjustment or using Poisson regression. RESULTS: Thirteen studies were included. Annual crude incidence rates in traumatic SCI varied from 12.1 per million in The Netherlands to 57.8 per million in Portugal. Compared to the Portuguese reference study, incidence rates showed a 3-fold variation, with the highest rates in Canada and Portugal. Most traumatic SCI studies showed a bimodal age distribution. The first peak was found in young adults between 15 and 29 years and a second peak in older adults (mostly > or = 65 years). Motor vehicle accidents and falls were the most prevalent causes of injury accounting for nearly equal percentages. In contrast, another age pattern in non-traumatic SCI reflected steadily increasing incidence with advancing age. CONCLUSIONS: The results show significant variation in SCI incidence with changing epidemiological patterns. A trend towards increased incidence in the elderly was observed, likely due to falls and non-traumatic injury.

Independent validation of the scales for outcomes in Parkinson's disease-autonomic (SCOPA-AUT).

BACKGROUND AND PURPOSE: Autonomic dysfunction is common in Parkinson's disease (PD) and causes a great impact in health-related quality of life (HRQL) and functional status of patients. This study is the first independent validation of the Scales for Outcomes in PD-Autonomic (SCOPA-AUT). METHODS: In an observational, cross-sectional study (ELEP Study), 387 PD patients were assessed using, in addition to the SCOPA-AUT, the Hoehn and Yahr staging, SCOPA-Motor, SCOPA-Cognition, Cumulative Illness Rating Scale-Geriatrics, modified Parkinson Psychosis Rating Scale, Clinical Impression of Severity Index for PD, Hospital Anxiety and Depression Scale, SCOPA-Sleep, SCOPA-Psychosocial, pain and fatigue visual analogue scales, and EQ-5D. SCOPA-AUT acceptability, internal consistency, construct validity, and precision were explored. RESULTS: Data quality was satisfactory (97%). SCOPA-AUT total score did not show floor or ceiling effect, and skewness was 0.40. Cronbach's alpha coefficients ranged from 0.64 (Cardiovascular and Thermorregulatory subscales) to 0.95 (Sexual dysfunction, women). Item homogeneity index was low (0.24) for Gastrointestinal subscale. Factor analysis identified eight factors for men (68% of the variance) and seven factors for women (65% of the variance). SCOPA-AUT correlated at a high level with specific HRQL and functional measures (r(S) = 0.52-0.56). SCOPA-AUT scores were higher for older patients, for more advanced disease, and for patients treated only with levodopa (Kruskal-Wallis test, P < 0.01). Standard error of measurement for SCOPA-AUT subscales was 0.81 (sexual, men) - 2.26 (gastrointestinal). CONCLUSIONS: Despite its heterogeneous content, which determines some weaknesses in the psychometric attributes of its subscales, SCOPA-AUT is an acceptable, consistent, valid and precise scale.

Prevalence of dementia subtypes in El Prat de Llobregat, Catalonia, Spain: the PRATICON study.

BACKGROUND: Studies on dementia subtypes show a wide variation in the prevalence of Alzheimer's disease (AD) and vascular dementia (VD) worldwide. However, studies reporting on Lewy body dementia (LBD) and frontotemporal dementia (FTD) are sparse. AIMS: To describe the prevalence of dementia and subtypes. METHOD: A 34% sample of 5,150 subjects aged 70 years and over in El Prat de Llobregat (Barcelona) were screened by the Mini-Mental State Examination. When scoring <24, participants were assessed to establish a diagnosis. RESULTS: There were 165 subjects diagnosed with dementia (prevalence of 9.4%). Subtypes of dementia were: AD 69.1%, VD 12.7%, LBD 9.1%, FTD 3% and secondary dementia 1.8%. Prevalences were: AD 6.5%, VD 1.2%, LBD 0.9% and FTD 0.3%. CONCLUSIONS: AD and VD were the most common type of dementia. Prevalence of dementia, AD and FTD were similar to those reported, while prevalence of VD and LBD were lower.

Determinants of diagnostic investigation sensitivities across the clinical spectrum of sporadic Creutzfeldt-Jakob disease.

To validate the provisional findings of a number of smaller studies and explore additional determinants of characteristic diagnostic investigation results across the entire clinical spectrum of sporadic Creutzfeldt-Jakob disease (CJD), an international collaborative study was undertaken comprising 2451 pathologically confirmed (definite) patients. We assessed the influence of age at disease onset, illness duration, prion protein gene (PRNP) codon 129 polymorphism (either methionine or valine) and molecular sub-type on the diagnostic sensitivity of EEG, cerebral MRI and the CSF 14-3-3 immunoassay. For EEG and CSF 14-3-3 protein detection, we also assessed the influence of the time point in a patient's illness at which the investigation was performed on the likelihood of a typical or positive result. Analysis included a large subset of patients (n = 743) in whom molecular sub-typing had been performed using a combination of the PRNP codon 129 polymorphism and the form of protease resistant prion protein [type 1 or 2 according to Parchi et al. (Parchi P, Giese A, Capellari S, Brown P, Schulz-Schaeffer W, Windl O, Zerr I, Budka H, Kopp N, Piccardo P, Poser S, Rojiani A, Streichemberger N, Julien J, Vital C, Ghetti B, Gambetti P, Kretzschmar H. Classification of sporadic Creutzfeldt-Jakob disease based on molecular and phenotypic analysis of 300 subjects. Ann Neurol 1999; 46: 224-233.)] present in the brain. Findings for the whole group paralleled the subset with molecular sub-typing data available, showing that age at disease onset and disease duration were independent determinants of typical changes on EEG, while illness duration significantly influenced positive CSF 14-3-3 protein detection; changes on brain MRI were not influenced by either of these clinical parameters, but overall, imaging data were less complete and consequently conclusions are more tentative. In addition to age at disease onset and illness duration, molecular sub-type was re-affirmed as an important independent determinant of investigation results. In multivariate analyses that included molecular sub-type, time point of the investigation during a patient's illness was found not to influence the occurrence of a typical or positive EEG or CSF 14-3-3 protein result. A typical EEG was most often seen in MM1 patients and was significantly less likely in the MV1, MV2 and VV2 sub-types, whereas VV2 patients had an increased likelihood of a typical brain MRI. Overall, the CSF 14-3-3 immunoassay was the most frequently positive investigation (88.1%) but performed significantly less well in the very uncommon MV2 and MM2 sub-types. Our findings confirm a number of determinants of principal investigation results in sporadic CJD and underscore the importance of recognizing these pre-test limitations before accepting the diagnosis excluded or confirmed. Combinations of investigations offer the best chance of detection, especially for the less common molecular sub-types such as MV2 and MM2.

Association of detected depression and undetected depressive symptoms with long-term mortality in a cohort of institutionalised older people.

BACKGROUND: Studies on depression and mortality in nursing homes have shown inconclusive findings, and none has studied the role of detection. We sought to measure the association of depression with long-term all-cause mortality in institutionalised older people and evaluate a potential modification in the association by its detection status. METHODS: We selected a stratified cluster sample of 591 residents aged 75 years or older (mean age 84.5 years) living in residential and nursing homes of Madrid, Spain, who were free of severe cognitive impairment at the 1998-1999 baseline interview. Mortality was ascertained until age 105 years or September 2013 (median/maximum follow-up 4.8/15.2 years) through linkage to the Spanish National Death Index. Detected depression was defined at baseline as a physician's diagnosis or antidepressant use, undetected depression as significant depressive symptoms (score of 4 or higher on the ten-item version of the Geriatric Depression Scale) without documented diagnosis or treatment, and no depression as the absence of diagnosis, treatment, and symptoms. Constant and age-dependent hazard ratios for mortality comparing detected and undetected depression with no depression were estimated using Cox models, and absolute years of life gained and lost using Weibull models. RESULTS: The baseline prevalences of detected and undetected depression were 25.9 and 18.8%, respectively. A total of 499 participants died during 3575 person-years of follow-up. In models adjusted for age, sex, type of facility, number of chronic conditions, and functional dependency, overall depression was not associated with long-term all-cause mortality (hazard ratio 0.87, 95% confidence interval (CI): 0.70-1.08). However, compared with no depression, detected depression showed lower mortality (hazard ratio 0.63, 95% CI: 0.46-0.86), while undetected depression registered higher, not statistically significant, mortality (hazard ratio 1.35, 95% CI: 0.98-1.86). The median life expectancy increased by 1.8 years (95% CI: -3.1 to 6.7 years) in residents with detected depression and decreased by 6.3 years (95% CI: 2.6-10.1 years) in those undetected. Results were more marked in women than men and they were robust to the exclusion of antidepressants from the definition of depression and also to the use of a stricter cut-off for the presence of depressive symptoms. CONCLUSIONS: The long-term mortality risk associated with depression in nursing homes depends on its detection status, with better prognosis in residents with detected depression and worse in those undetected. The absolute impact of undetected depressive symptoms in terms of life expectancy can be prominent.

Predictors of survival in sporadic Creutzfeldt-Jakob disease and other human transmissible spongiform encephalopathies.

A collaborative study of human transmissible spongiform encephalopathies has been carried out from 1993 to 2000 and includes data from 10 national registries, the majority in Western Europe. In this study, we present analyses of predictors of survival in sporadic (n = 2304), iatrogenic (n = 106) and variant Creutzfeldt-Jakob disease (n = 86) and in cases associated with mutations of the prion protein gene (n = 278), including Gerstmann-Sträussler-Scheinker syndrome (n = 24) and fatal familial insomnia (n = 41). Overall survival for each disease type was assessed by the Kaplan-Meier method and the multivariate analyses by the Cox proportional hazards model. In sporadic disease, longer survival was correlated with younger age at onset of illness, female gender, codon 129 heterozygosity, presence of CSF 14-3-3 protein and type 2a prion protein type. The ability to predict survival based on patient covariates is important for diagnosis and counselling, and the characterization of the survival distributions, in the absence of therapy, will be an important starting point for the assessment of potential therapeutic agents in the future.

Studies on the prevalence of paralysis agitans by tracer methodology.

The present study was motivated by the methodological issues revealed by a review of previous studies on Paralysis Agitans (PA) epidemiology. The study was given the following aims: To identify an easy available, inexpensive marker of PA frequency in populations; to develop, standardize and validate a model for measurement of PA prevalence by using that tracer; to study the geographical distribution of PA in Sweden, and to use the model in environmental risk analysis (ERA) for PA. Information on diagnoses and anti-parkinsonian drugs (APD) utilization from Swedish registers was analyzed, in order to select the group of APD which would best fulfill the prerequisites of specificity and preference of choice, and combined with prevalence data from direct surveys. Levodopa drugs were found to be the most suitable tracer for PA prevalence. A mathematical model was formulated to generate annual estimates for average age specific prevalences from total sales of levodopa, age specific population and figures for infant mortality rates. The following was required in order for the model to yield accurate estimates: high quality of the information to be used, good availability of levodopa drugs, a minimal size of the studied population of 100,000, an IMR lower than 28.8 per 1000 and that levodopa diffusion had reached the late adoption phase. Underdiagnosis was found to constitute an important cause of bias in classical surveys. Standardization for age and health services effectiveness by using infant mortality rates was shown to improve comparability of prevalence figures. The model was validated and showed internal consistency for age specific data on levodopa sales and on prevalence from Sweden and six Chinese towns, respectively. Estimates for prevalence for Iceland and Sardinia fitted historical data from direct surveys. The results of the ERA study showed that a high latitude and a low population density in 1900-20 were correlated with an increase in PA prevalence as measured by surveys or estimated by the use of the tracer method. Further analysis indicated that several so-called risk factors or concomitant diseases are associated with low population density. The geographical distribution of standardized PA prevalences in Swedish counties was studied for the period 1977-84. The findings were in accordance with the figures expected from the natural characteristics of the disease as determined by latitude and population density except in the county of Gävleborg which showed a significantly higher, and continuously increasing prevalence.(ABSTRACT TRUNCATED AT 400 WORDS)

Incidence of optic neuritis in Stockholm, Sweden, 1990-1995: II. Time and space patterns.

OBJECTIVES: To describe the time and space patterns of patients with monosymptomatic optic neuritis (MON) in Stockholm County, Sweden, and to explore the role of environmental factors in the etiology of MON and multiple sclerosis. DESIGN: Population-based and prospective incidence survey. SETTING: Census based on referrals from 1.68 million inhabitants of Stockholm County. PATIENTS: One hundred forty-seven new patients with MON were consecutively referred by ophthalmologists and neurologists from January 1, 1990, through December 31, 1995. A standardized questionnaire was used for data collection. MAIN OUTCOME MEASURES: Evaluations consisted of annual incidence, statistical significance of temporal aggregation, Knox test, likelihood score test applied to the ratio of the highest to lowest seasonal proportion of registered events, and standardized morbidity ratio for municipalities. RESULTS: We observed a seasonal pattern of MON incidence, with the highest incidence (31%) in the spring and the lowest (17%) in the winter (ratio of highest to lowest seasonal proportion, 1.84; 95% confidence interval, 1.13-3.01; P = .007). The seasonal monthly incidences were correlated with the average number of sunny hours and the temperature. The presence of positive immune activity markers (i.e., mononuclear pleocytosis and oligoclonal IgG bands in the cerebrospinal fluid) seemed to be linked to the onset of MON in winter. No aggregation by time, space, or month of birth was detected. CONCLUSIONS: Monosymptomatic optic neuritis in Stockholm County occurred at an uneven frequency across the seasons, with the highest incidence in spring and the lowest in winter. This seasonal pattern is compatible with that described in most previous reports. Environmental and probable infectious factors unevenly distributed by season may play a role in the etiology and early clinical course of MON.

Analysis of EEG and CSF 14-3-3 proteins as aids to the diagnosis of Creutzfeldt-Jakob disease.

OBJECTIVE: To improve diagnostic criteria for sporadic Creutzfeldt-Jakob disease (CJD). METHODS: Pooled data on initial and final diagnostic classification of suspected CJD patients were accumulated, including results of investigations derived from a coordinated multinational study of CJD. Prospective analysis for a comparison of clinical and neuropathologic diagnoses and evaluation of the sensitivity and specificity of EEG and 14-3-3 CSF immunoassay were conducted. RESULTS: Data on 1,003 patients with suspected CJD were collected using a standard questionnaire. After follow-up was carried out, complete clinical data and neuropathologic diagnoses were available in 805 cases. In these patients, the sensitivity of the detection of periodic sharp wave complexes in the EEG was 66%, with a specificity of 74%. The detection of 14-3-3 proteins in the CSF correlated with the clinical diagnosis in 94% (sensitivity). The specificity (84%) was higher than that of EEG. A combination of both investigations further increased the sensitivity but decreased the specificity. CONCLUSIONS: Incorporation of CSF 14-3-3 analysis in the diagnostic criteria for CJD significantly increases the sensitivity of case definition. Amended diagnostic criteria for CJD are proposed.

Differential features of motor neuron disease mortality in Spain.

BACKGROUND: The objective of this study was to describe the temporal and spatial patterns of motor neuron disease (MND) in Spain. METHODS: We studied data where MND was stated as the principal cause of death in official statistics from Spain. Time trends were analysed for age-, sex-specific and age-adjusted rates for the period 1951-1990. Age-adjusted mortality and relative risk, obtained by Poisson regression adjusting for age, were calculated for each province from deaths during the period 1975-1988. Maps were constructed using log transformed rates. Statistical significance of spatial aggregation was assessed using the Ohno et al. test. RESULTS: The 1951-1990 mortality rate, age- and sex-adjusted to the European population, for the population aged > or = 40 years was 1.49 per 100,000; 1.90 and 1.21 for males and females respectively. In general, mortality increased with age. Age-adjusted rates rose until 1960, dropped by 70% during the 1960s and declined slightly over the 1951-1990 period as a whole. From 1970 onwards MND mortality rose evenly, particularly in the 60-69 age group. A North-South gradient was suggested for both sexes with statistically significant clustering in the Northern coastal regions and--for males alone--in the Midwest provinces. CONCLUSIONS: Mortality from MND in Spain displayed a magnitude and recently rising temporal trend similar to that described in several other countries. Specific traits were: a decrease during the 1960s, which has been described for Japan only, as well as spatial heterogeneity and a predominant recent increase among the 60-69 age group. The determinants of these unusual MND mortality patterns are unknown.

Whooping cough and Parkinson's disease. The Europarkinson Preparatory Activity Research Group.

BACKGROUND: We reported high levodopa use and prevalences of Parkinson's Disease (PD) in periodically, time-clustered, icelandic cohorts born after major whooping cough epidemics (MWCE). METHODS: In order to quantify a possible relationship between age at first post-birth MWCE and risk of PD we: 1) calculated cumulative incidences of PD during the period 1954-1963 in one-year Icelandic cohorts born between 1869 and 1927, using raw material from a reported survey; 2) identified MWCE from 1869 onwards in Iceland; 3) estimated cohort ages at onset of incidence period and at first MWCE; and 4) combined the above-mentioned information using log-linear models. In addition, we studied the prevalence of levodopa users in Icelandic birth cohorts during a recent period. RESULTS: The curves of the above-mentioned incidences and prevalences in one-year birth-cohorts showed: 1) a similar, age-related, inverted V profile; and 2) a systematic notchy pattern, with peak values for one or both measurements for cohorts born during or after each of nine MWCE identified during the period 1869-1927. When 13 cohorts born in years with MWCE were excluded from the analysis, the risk of PD rose with age at first defined MWCE, with the linear increase being 8.4% per year (95% CI: -0.1-18.3%). CONCLUSIONS: These results are consistent with reported effects of age at exposure in animal models of toxic parkinsonism, age-related changes in the dopamine receptor-GPT-binding protein-adenylatecyclase system observed in rats treated with pertussis toxin, and some PD epidemiological features. They suggest that pertussis neurotoxicity could be casually treated to PD worldwide.

Seasonal patterns in optic neuritis and multiple sclerosis: a meta-analysis.

To quantify and characterize seasonal variation in monosymptomatic optic neuritis (MON) onsets, multiple sclerosis (MS) onsets and MS exacerbations (MSE), a meta-analysis was performed, using established methods and pooling weighted information obtained from nine reports on MON, six reports on MS onsets and nine reports on MSE, which fulfilled specific criteria for report quality and data homogeneity. The results suggested that MON, MS onsets and MSE in the Northern hemisphere present a similar pattern with highest frequencies in spring and lowest in winter. These differences were highest for MS onsets, 45% with 95% CI 36-55%, and lowest for MSE, 10% with 95% CI 7-13%, statistically significant and robust, insensitive to an alternative seasonal definition, not unduly influenced by any single primary study, and supported by fail-safe N calculations. Random variation, misclassification and publication bias were less likely to account for the reported generalized seasonal patterns.

Time-trend analysis of mortality from malignant tumors of the nervous system in Spain, 1952-1986.

We analyzed time trends in mortality from malignant tumors of the nervous system (MTNS) in the adult Spanish population during the period 1952-1986, using Poisson regression analysis of age at death, year of birth and year of death. During such period, mortality rose especially in the elderly as well as among young and middle-aged men. We found two modest period effects, in both sexes attributed to changes in certification practice. An ascending effect in cohorts born up to 1920 in males and females was attributed to improvements in ascertainment. A positive, progressive, cohort effect in males born post-1920 was detected. Mortality from MTNS in Spain was medium-high with a tendency to rise, most likely due to improvements in diagnosis and registration. From this analysis, the existence of a true increase in incidence of brain glioma among young and middle-aged male adults during recent decades is suggested.

Incidence of optic neuritis in Stockholm, Sweden 1990-1995: I. Age, sex, birth and ethnic-group related patterns.

We studied the incidence of monosymptomatic optic neuritis (MON) in Stockholm county, Sweden and its variation with person-related factors. Patients with suspected or diagnosed MON between January 1, 1990 and December 31, 1995 were referred from ophthalmologists and neurologists to a research registry. The diagnosis was based on accepted clinical criteria only, and verified by an ophthalmologist who examined all the patients. Data were collected by interview using a structured questionnaire. The crude mean annual incidence, based on 147 patients, 118 females and 29 males, diagnosed with MON, was 1.46 per 100,000 person-years, 2.28 for females and 0.59 for males. The corresponding age-adjusted incidences were 1.40, 2.28 and 0.53. The age-specific incidence curve for both sexes suggested a bimodal distribution with peaks at 30-34 years and 45-49 years. The smoothed cumulative incidences in 1 year birth cohorts showed a notchy profile, related to bimodality. The incidence among residents born out of the Nordic countries was low, 0.28 per 100,000. Patients with onset of MON before 40 years of age had a significantly higher frequency of mononuclear pleocytosis in cerebrospinal fluid and shorter duration to conversion to multiple sclerosis. In summary, MON occurred in Stockholm at a relatively low frequency, particularly among males. The presence of particular birth date and birth place related patterns might be etiologically relevant.