G. Rosati

Studies on epidemiological, clinical, and etiological aspects of ALS disease in Sardinia, Southern Italy.

This investigation was conducted to clarify the epidemiology of ALS disease in Sardinia. During the years 1965–1974, the average annual incidence was found to be 0.64/100,000 inhabitants. On prevalence day, October 24st, 1971, the prevalence rate was 1.56/100,000 inhabitants. A significant male predominance was found, the average annual incidence rates for men and women being 0.88 and 0.40 respectively. The peak in both sexes was reached between 60 and 69 years. ALS distribution in the study area was uniform but its occurrence was significantly higher among agricultural workers (5.28/100,000). ALS started on average at 56.58 years and its duration was 2.5 years, being significantly longer in patients under 40‐years‐old. The distribution of the various clinical forms was: 66 per cent conventional forms, 20 per cent bulbar and 14 per cent pseudo‐polyneuritic. In the bulbar type, a female predominance was found. About 96 per cent of cases were sporadic and 4 per cent familial. Familial cases presented no difference from sporadic cases. Trauma was present in 10.5 per cent of the cases and gastrointestinal disfunction in 13 per cent. This probably reflects some relationship between trauma and ALS, and between malnutrition and ALS. No combination of ALS, dementia and parkinsonism was observed. Dementia was associated with ALS in four cases and Parkinsons disease in one case, separately. The combination of other disease states with ALS in the present study may be simple coincidence.

Multiple sclerosis epidemiology in Sardinia : evidence for a true increasing risk

Objectives– To update prevalence and incidence rates of MS among Sardinians. Materials and methods– The present work is a “spider” kind of population based survey, conducted over the interval 1968–97, on patients with MS (Poser criteria) living in the province of Sassari, Northern Sardinia (454,904 population). Results– A crude total prevalence rate of 144.4 per 100,000, an onset‐adjusted prevalence rate of 149.7 per 100,000 and an average annual incidence rate of 8.2 for the period 1993–7 were found. Conclusion– Repeated epidemiological assessments of MS in Sardinia over decades have shown that the island is at high risk for MS. The present work highlights that MS incidence in Sardinia has been increasing over time. Although a substantial and widely spread improvement in MS case ascertainment can be postulated as the reason for such observations, a comparison between our data and those recently reported from a more industrialized province in Northern Italy seems to prove an at least partially real increase in MS risk among Sardinians and favours the hypothesis of a MS “Sardinian focus” as related to its latitude.

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.

The risk of Parkinson disease in Mediterranean people

On the basis of previous epidemiologic studies, Parkinson disease was thought to be evenly distributed throughout the world. These studies, however, were conducted only on North European populations. The position with regard to the Mediterranean peoples was still unknown, and we therefore studied the frequency of Parkinson disease on the island of Sardinia, where some ethnic groups of the Mediterranean stock are represented. Based on 967 accepted cases, the prevalence per 100,000 population on January 1, 1972, was 65.6; the average annual incidence for the period 1961 through 1971 was 4.9. These figures are one-half of the figures established for North Europeans. Our findings suggest racial differences in predisposition to Parkinson disease. Some Negroid features are present in Sardinians. If, as seems likely, Africans prove to be relatively unsusceptible to the disease, the risk for Sardinians and other Mediterranean ethnic groups might be intermediate between North Europeans and Africans.

Multiple sclerosis–associated retrovirus and MS prognosis An observational study

Abstract—MS-associated retrovirus (MSRV) in the CSF may have gliotoxic properties and could be associated with a more disabling MS. The authors tested this hypothesis in 15 untreated patients with MS: 6 MSRV− and 9 MSRV+ at the time of CSF withdrawal. After a 3-year mean follow-up, MSRV− patients showed a stable MS course, whereas MSRV+ patients had a progressive course (p = 0.01).

Clinical and audiological findings in a case of auditory agnosia

SummaryA case is reported of severe agnosia for verbal and non-verbal sounds without associated aphasic disorder. A CT scan revealed bilateral, temporal lobe lesions from two ischaemic accidents that had occurred 9 months apart. The search for subtle deficits in this patient showed normal sensitivity to changes in the intensity and frequency of simple sounds; in contrast, his ability to discriminate sound duration and musical note sequences was severely impaired. The simultaneous recording of the whole auditory-evoked response pattern revealed no abnormality in the early components, which reflect the activation of the auditory nuclei and pathways of the brain stem. However, the middle and late components were delayed and slowed. These results and others in the literature suggest that the neocortex in man, as in other mammals, plays an essential role in the temporal aspects of hearing. Also, the two main ingredients commonly recognized in auditory agnosia, i.e. word deafness and the inability to interpret non-verbal sounds, are caused by the disruption of elementary, bilaterally represented cortical functions which start the processing of every kind of auditory information.

Static vestibulospinal influences in relation to different body tilts in man

In this study, H-reflex testing was used to identify possible static vestibular influences on soleus alpha motoneuron excitability in man in relation to different body tilts. Ten normal adult volunteers and one labyrinthine-defective patient were tested in an experimental situation designed to minimize all afferent inputs except the vestibular ones. Each subject was fixed to a rigid platform inclinable from the horizontal (0 degree) to the vertical (90 degrees) position and vice versa. On each subject, 10 consecutive H reflexes were recorded for each of the following positions: 0 degree, 15 degrees, 30 degrees, 45 degrees, 60 degrees, 75 degrees, 90 degrees and 90 degrees, 75 degrees, 60 degrees, 45 degrees, 30 degrees, 15 degrees, 0 degree. In all normal subjects, we observed a significant increase in amplitude of the H reflex as the body was tilted from horizontal to vertical, and a significant decrease when the body was returned to the original position. These progressive changes in spinal motoneuron excitability were linearly related to the tilt angles. By contrast, no significant change in H-reflex amplitude was observed in the labyrinthine-defective patient. These results would seem to indicate that the vestibular system exerts some influences on antigravity muscles in static tilts and that these influences are behaviorally adequate to provide for the postural stability.

The frequency of multiple sclerosis in Mediterranean Europe: an incidence and prevalence study in Barbagia, Sardinia, insular Italy

Recent investigations on multiple sclerosis (MS) distribution in Italy, based on relatively small population groups, contradict the current thesis, derived from studies undertaken in populations exceeding 300,000, of a lower spreading of the disease in Mediterranean Europe. Intensive surveys on small populations strengthen the suggestion that Italy is a high‐risk area, although MS studies based on prevalence rather than incidence could also be biased by geographic variables making prevalence unsuitable for comparing MS prevalence rates found in different years and/or zones. We report a further epidemiologic study in Barbagia, Sardinia, insular Italy, undertaken both to establish the MS incidence in the last 20 years, and to estimate a new prevalence rate. Based on 31 probable incident cases, the mean incidence per year for the years 1961‐1980 was 2.9 per 100,000 (3.2 if age‐ and sex‐standardized to the Italian population). On October 24, 1981, the prevalence per 100,000 was 65.3 (77.9 if standardized to the Italian population). These results confirm that in Barbagia, MS occurs more frequently than expected in a Mediterranean area, and give further support to the idea that MS frequency in Italy is similar to that established for most central and northern European countries.

Pure agraphia: a discrete form of aphasia.

A 62 year old, right handed man developed a pure agraphia as the result of a left temporal lobe stroke. Isolated writing disturbances persisted for seven months until he had a second cerebrovascular accident resulting in total aphasia and right hemiplegia. A CAT scan obtained four months after the first episode showed a localised dilatation of the posterior portion of the left Sylvian cistern and patchy areas of low absorption in the left temporal lobe. The report supports suggestions that localised damage to the language area can produce a pure agraphia as the sole detectable disorder of language organisation.

Successful treatment of acquired pendular elliptical nystagmus in multiple sclerosis with isoniazid and base‐out prisms

We treated 3 multiple sclerosis patients who had pendular nystagmus with isoniazid (800 to 1,000 mg/d). Isoniazid abolished the nystagmus and relieved oscillopsia in 2 patients but was ineffective in the 3rd in whom the nystagmus was damped with convergence and vision improved with converging (base-out) prisms.