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I Casetta

Publications and source records attributed to I Casetta.

At least 19 recordsLinked to original sources
PubMed2001

Multiple sclerosis: infectious hypothesis.

In the search for the etiology of multiple sclerosis (MS), consideration has been given in turn to infectious agents, to genetic markers, and more recently to a combination of genetic and environmental factors, but after over a century of research, a definite conclusion has not been reached. The hypothesis that an infectious agent is responsible for triggering MS is perhaps one of neurology's most enduring notions. Interest in an infectious etiology has waxed and waned over the last two centuries since Pierre Marie first proposed that MS often starts as an infectious process. The possible role of infectious agents has been suggested by: the different geographic gradients in frequency among Caucasians; changes in prevalence due to migration, and the effect of age at migration; the suggestion of epidemics and clusters of cases in some small communities; and the remarkably low degree of concordance in monozygotic twins. The infectious hypothesis is strongly supported by the different temporal patterns of the disease in different geographic areas. Incidence rates have remained stable in some areas, but have changed over time in other regions. On the other hand, the hypothesis is hampered by the lack of evidence for a specific agent, and the weakness of the results of analytical studies that have tested the association between MS and previous infections. Despite these drawbacks, recent studies of a few select pathogens suggest that viral or bacterial infections or reactivations may trigger clinical exacerbations in relapsing-remitting MS.

Adult↗
PubMed2001

Multiple sclerosis and dental amalgam: case-control study in Ferrara, Italy.

Dental amalgam fillings containing mercury have been suggested as a possible risk factor for multiple sclerosis (MS). In the context of a wider program of investigation into environmental risk factors and MS, we conducted a case-control comparison to investigate the alleged association between MS, dental caries, and amalgam fillings. We included 132 MS patients with onset during the last 16 years and 423 controls, matched to cases for sex, age and residence. Data were collected by a personal interview conducted by trained doctors. Cases and controls gave informed consent. Although we report a trend toward a higher number of dental fillings in cases than controls, odds ratios for subjects with exposures of different duration and with different numbers of amalgam fillings were not statistically significant. This case-control study failed to demonstrate an association between either the number of dental amalgam fillings or the duration of exposure to mercury amalgam and MS.

Adult↗
PubMed2000

The increasing incidence and prevalence of MS in a Sardinian province.

OBJECTIVE: To verify incidence rates and their temporal trend in a homogeneous, ethnically, and genetically distinct population of central Sardinia (the Nuoro province). BACKGROUND: Intensive epidemiologic studies carried out in Sardinia since the 1970s have suggested that the prevalence and incidence of MS are much higher in this Mediterranean island compared with those found on mainland Italy. METHODS: The study area had a population of approximately 274, 000 people in the 1991 census. The authors adopted a complete enumerative approach by reviewing all possible sources of case collection available in the investigative area. RESULTS: Based on 469 MS patients, the mean annual incidence for 1955 to 1995 was 4.18 per 100,000 (or 4.3 per 100,000 if age- and sex-adjusted to the European population). The incidence, averaging 1.95 per 100,000 during 1955 to 1959, rose progressively over time, reaching rates of 6.6 in the quinquiennium 1985 to 1989 and 6.4 per 100,000 in 1990 to 1995. On December 31, 1994, the crude prevalence, based on 415 MS patients alive in the study area, was 151.9 per 100,000 (156.6 if adjusted to the European population). CONCLUSION: These incidence and prevalence rates are the highest to date that have been estimated for a large community in southern Europe, and they constitute some of the highest rates in the world. Based on other surveys, these results reinforce the position of Sardinia as a higher and rising prevalence area for MS compared with other Mediterranean populations. Genetic and social-historic data strengthen the hypothesis of the environmental role and genetic factors among Sardinians in determining the notable difference in MS frequency between Sardinians and other Mediterraneans.

Adolescent↗
PubMed2000

Prognosis of multiple sclerosis: environmental factors.

Epidemiological data have suggested a role for environmental factors in multiple sclerosis etiology. Infectious diseases, exposure to toxins, immunizations, nutritional and hormonal variables, and trauma are the most studied and biologically plausible risk factors for MS. Their putative role in determining or simply triggering MS development in genetically prone subjects suggests a possible involvement of the same factors in modulating the subsequent behavior of the disease and its prognosis.

Environmental Exposure↗
PubMed2000

Clinical infections and multiple sclerosis: contribution from analytical epidemiology.

Epidemiological studies have suggested that exogenous factors may play a role in the etiology of multiple sclerosis and that the environmental component may be viral, but, as yet, there is insufficient evidence to draw any definite conclusions concerning any of the viruses so far proposed. The case-control approach failed to give any definitive conclusion. While the frequency of each common childhood illness is not significantly different between cases and controls, there are more consistent data suggesting that cases do report a later age at infections: this applies particularly to measles, rubella, mumps and EBV infection. Several studies have proved that viral or bacterial infections or reactivations could trigger the clinical attacks in relapsing-remitting MS.

Humans↗
PubMed1999

The frequency of clinical variants of Guillain-Barré syndrome in Ferrara, Italy.

As the available diagnostic criteria (National Institute of Neurological and Communicative Disorders and Stroke, NINCDS) for Guillain-Barré syndrome (GBS) do not permit inclusion of clinical variants (CV) of GBS, there are few data on their occurrence and few reports of the overall incidence of the disease. A population-based study in the local health district of Ferrara, Italy in 1981-1993 selected cases fulfilling both NINCDS criteria (NINCDS GBS cases) and CV. The incidence of CV was 0.35 per 100,000 person-years (95% CI: 0.15-0.68), 0.32 when age-adjusted to the Italian population. No difference was found between CV and NINCDS GBS for male/female ratio, mean age at onset, elevated CSF protein content, seasonal pattern, or mean time delay from first neurological symptom to maximal severity. A higher frequency of antecedent infections for CV and more frequent serious disease at the nadir time for NINCDS GBS were found. A complete recovery was more frequent for CV than NINCDS GBS, but no difference was found regarding good outcome (defined by a satisfactory recovery and resumption of normal functional life). Since most findings were similar for NINCDS GBS and CV cases, they may have similar underlying pathological mechanisms. When diagnostic criteria for GBS include CV, the overall disease incidence in the Ferrara district increases from 1.87 to 2.21 cases per 100,000 person-years (the contribution of CV to the overall incidence of GBS is 15.7%). The currently available diagnostic criteria for GBS, although useful for field studies, may be too restrictive as they can entail the loss of about 15% of cases.

Adolescent↗
PubMed1999

Early predictors of intractability in childhood epilepsy: a community-based case-control study in Copparo, Italy.

OBJECTIVES: To identify early predictors of intractability in childhood and adolescence epilepsy. MATERIALS AND METHODS: We carried out a community-based case-control study using the incidence cohort of epileptic patients living in the district of Copparo, in the province of Ferrara, Italy. The comparative study was performed in 31 cases and 95 controls. Cases were patients who averaged at least 1 unprovoked seizure per month during an observational period of at least 2 years. Controls were subjects having achieved remission for at least 5 years regardless of current therapy. RESULTS: Onset at age <1 year, remote symptomatic etiology and high frequency of seizures before therapy were found to be independent early predictors of intractability. CONCLUSION: Our study suggested that the risk of developing intractable epilepsy may, to some extent, be predicted at the time of initial diagnosis in children with early-onset epilepsy of remote symptomatic etiology, especially if seizure propensity is initially high.

Adolescent↗
PubMed1999

Temporal trend and factors associated with delayed hospital admission of stroke patients.

The effectiveness of stroke treatment depends on the time interval between onset of symptoms and admission to hospital. The purpose of our investigation was to assess, over a 10-year period, the mean delay in admission to hospital in stroke patients to determine factors which might be associated with this delay, to define the putative number of patients available for accrual in clinical trials, and to identify strategies aimed at decreasing the time to admission. We collected data on all stroke patients consecutively admitted to our clinic from 1986 to 1995. The following variables were investigated: age, sex, educational and occupational level, home accommodation, family and personal history of vascular disease or factors known to affect the risk of vascular disease, and type and severity of stroke. The individual and independent contribution of these variables was assessed by univariate and multivariate analysis. The accurate time of stroke onset was established for 760 patients. Of these, 24.7% were admitted within 1 h from the onset of symptoms, 41% within 2 h, 54% within 4 h and 72.5% within 12 h. The mean delay was 21 +/- 2 h (SE) and the median was 3.5 h. Acute onset of neurological deficits, stroke severity and family history of cerebrovascular disease were associated with earlier presentation. According to the current guidelines for thrombolytic therapy, only 16% of the patients could have been included in a clinical trial. This study suggests that despite a relatively short time to hospital admission in most patients and an altered help-seeking behavior over time, many stroke patients did not present early enough to be recruited for clinical trials or to benefit from new treatments. The majority of patients with timely presentation were not eligible for acute treatment, or were subjects with severe stroke for whom caution is advised before initiating thrombolytic therapy. It has been suggested that the patient's indecision to seek medical help is the most important reason for a delayed hospital admission of stroke patients. These results underscore the importance of interventions aimed at reducing the delay in stroke treatment induced by patients who are unaware of the decisive role of the time of treatment induction. The finding that earliest admissions for stroke comprised patients with a previous history of cerebrovascular disease suggests that an education campaign might highlight the importance of an early admission.

Adult↗
PubMed1998

Transient global amnesia and transient ischemic attack: a community-based case-control study.

OBJECTIVES: Few case-control studies of first-ever transient global amnesia (TGA), transient ischemic attack (TIA) and normal controls have been performed to date. We aimed to assess the prevalence of cerebrovascular risk factors in a well defined population of TGA patients. MATERIAL AND METHODS: We undertook a retrospective and prospective community-based case-control study of 170 first-ever TGA, 170 first-ever TIA and 170 normal controls. RESULTS: Age-matched analysis revealed that TGA cases had a significantly lower prevalence of atrial fibrillation and diabetes mellitus than TIA controls. The prevalence of cigarette smoking and diabetes mellitus was significantly higher in normal controls than in TGA cases. CONCLUSION: Our community-based case-control study showed that atrial fibrillation and diabetes mellitus, two important risk factors for cerebrovascular disease, were significantly more common in the TIA group than in the TGA one. These results make the thromboembolic pathogenesis of TGA unlikely.

Amnesia↗
PubMed1998

An epidemiological study of multiple sclerosis in central Sardinia, Italy.

OBJECTIVES: To verify morbidity estimates in central Sardinia, Italy. METHODS: A prevalence study was performed in the province of Nuoro, Central Sardinia, which has a population of 273,768 inhabitants (135,383 men and 138,385 women). A complete enumeration approach was adopted by using all possible case-collection sources. RESULTS: On prevalence day, December 31, 1993, 394 subjects (124 men and 270 women) living in the study area were known to suffer from definite and probable MS, giving a crude prevalence rate of 143.9 cases per 100,000 people, 91.6 for males and 195.11 for females. The crude prevalence estimated on December 31, 1985, based on 282 MS cases alive in the study area, was 102.94 per 100,000. CONCLUSION: This study reinforced central Sardinia's position as a high and rising prevalence area for MS.

Adolescent↗
PubMed1997

Exogenous gangliosides and Guillain-Barré syndrome. An observational study in the local health district of Ferrara, Italy.

A retrospective study was carried out in the Ferrara Local Health District, Italy, for the period 1981-1993 (average resident population: 177,235 inhabitants) to establish whether people exposed to exogenous gangliosides had a higher risk of Guillain-Barré syndrome. The incidence of Guillain-Barré syndrome of 1.9/100,000 population/year [95% confidence interval (CI): 1.3-2.5] reported in Ferrara Local Health District in the same period was used as a reference for comparison. The data bank of Ferrara Local Health District made it possible, first to estimate the number of individuals exposed to gangliosides in the resident population of Ferrara Local Health District (3.7%), the number of ganglioside prescriptions and the number of cases of Guillain-Barré syndrome who had treatment with gangliosides (nine patients, 20.9%), and, secondly, to verify the sequence of events between the ganglioside injection and the onset of the disease. Seven of the nine patients (77.8%) received gangliosides as treatment for peripheral neuropathy (Guillain-Barré syndrome onset before gangliosides were prescribed). For the other two patients (22.2%) a possible appropriate temporal sequence between ganglioside injection and onset of Guillain-Barré syndrome was found. Based on two possible ganglioside-related cases, the risk of Guillain-Barré syndrome was higher in the exposed (0.53/100,000 population/month following ganglioside injection; 95% CI: 0.06-1.91) compared with the unexposed population, but the difference was not significant. When only individuals prescribed with mixed gangliosides were considered (both possible ganglioside-related Guillain-Barré syndrome cases received mixed gangliosides), the risk of Guillain-Barré syndrome was higher (0.64/100,000 population/month following ganglioside injection; 95% CI: 0.08-2.31) but the difference from the risk in unexposed individuals was not statistically significant. The relative risk for the exposure to mixed gangliosides was borderline (relative risk = 4.3; 95% CI: 1.0-17.8). The wide 95% confidence intervals were a consequence of sample size limitations. Considering also that the exposed and unexposed groups differed in age (those exposed were older than those unexposed and the age-specific incidence of Guillain-Barré syndrome in the study population increased with increasing age), the present findings question either a strong increased risk of Guillain-Barré syndrome in people exposed to exogenous gangliosides or an immunogenic role of these agents in humans. However, because of the limited sample size, the results are not conclusive.

Adolescent↗
PubMed1997

Incidence of transient global amnesia in the Belluno province, Italy: 1985 through 1995. Results of a community-based study.

INTRODUCTION: We sought to determine the incidence rate of all the new cases of first-ever-in-a-lifetime transient global amnesia in the Belluno province, Italy. Only two prospective epidemiological studies on TGA incidence have been performed to date, non in Italy. Our study aimed to provide reliable and comparable information on TGA incidence. MATERIAL AND METHODS: We undertook a prospective population-based study in the territory of the province of Bulluno, Italy, between June 1, 1992 and December 31, 1995. We also retrospectively reviewed the clinical records of all the patients with a diagnosis of amnesia seen in the hospitals of the study area from January 1, 1985 through May 31, 1992. RESULTS: During the prospective study period we identified 77 patients who experienced a first-ever TGA. The crude annual incidence rate was 10.4/100,000 (9.35/100,000 for men and 11.37/100,000 for women). After adjustment to the European population, the incidence rate decreased to 8.60/100,000 per year. The crude annual incidence rate during the retrospective study period was 5.81/100,000. The demographic and clinical features of the two groups did not differ one to the other. CONCLUSIONS: The incidence rate of first-ever TGA registered in the province of Belluno, Italy, was closely similar to that reported in Turku, Finland and confirms that TGA is more common than has been usually proposed. We emphasize the usefulness of prospective, rather than retrospective, epidemiological studies for research on TGA.

Adult↗
PubMed1997

Prognosis of childhood epilepsy: a community-based study in Copparo, Italy.

We performed a community-based study among children and adolescents with idiopathic and cryptogenic epilepsy and onset of the seizures between 0 and 19 years of age on the prognosis of being seizure-free. The study population was recruited during a descriptive investigation in the Local Health Service of Copparo (USL 34), Ferrara, Northern Italy. We included 111 patients (61 males and 50 females). The average length of follow-up was 18.8 years (ranging from 7 to 24 years). The cumulative probability of being in remission was 81.2% at 15 years after onset and the estimated percentage of patients in remission without therapy was 56% for the same time period. At 15 years after the onset of epilepsy, approximately 20% of patients continued to have seizures; nearly 25% continued to take antiepileptic drugs but had been free of seizures for at least 5 years; nearly 56% had been without seizures and free of medication for at least 5 years. Seizure type, gender, age at onset of the illness, epileptic abnormalities on EEG, family history of convulsive disorders, number and frequency of seizures prior to the start of treatment were found not to be helpful as prognostic factors. This community study, carried out on patients without the well known factors that adversely affect prognosis, confirms that the prospect of seizure control and for withdrawal of therapy is (generally) good.

Adolescent↗
PubMed1997

Phenytoin-induced gingival overgrowth: a community-based cross-sectional study in Ferrara, Italy.

A community-based cross-sectional study was carried out in Ferrara, Northern Italy, to verify the frequency of gingival overgrowth in chronic phenytoin (PHT) users and the risk factors associated with its development. All subjects taking phenytoin were identified using the computerized list of drug prescriptions available in the study area. Most of the subjects were interviewed and underwent an oral examination to evaluate their periodontal condition. The prevalence of gingival enlargement in chronic PHT users was about 40%. In our study, sex, age age at onset of therapy, treatment duration, and oral hygiene were not significantly associated with the risk of developing gingival overgrowth. A direct relationship with daily dose was found to be an independent risk factor. Younger age and poorer oral hygiene seemed to predispose to the severest level of gingival involvement. These results support data from experimental studies by suggesting that drug-induced gingival overgrowth is a dose-dependent side effect whose severity could be affected by local factors.

Adolescent↗