Prevalence and incidence of multiple sclerosis in Salerno (southern Italy) and its province

Many multiple sclerosis (MS) prevalence studies in Italian northern and central areas, since 1980, have put Italy in a high risk zone; none concerns southern Italy. The MS registry of Salerno Center was reviewed, including the city and 16 towns at different distances (9–149 km) better connected to our Center. Population screened: 259 681 persons (Salerno = 136 678; province = 123 003). Prevalence day was December 31, 2005. Data on 186 patients were collected of which 55 were males, 131 females; crude total prevalence = 71.6263 (62.03–82.303, ranging from 50.1128 (Oliveto Citra) to 431.499 (Controne). Salerno prevalence rate is 70.9697 (57.41–86.583); standardized = 72.02. Incidence rate ranges from 2.38585 (1.6–3.39) (1991–95) to 4.31997 (3.24–5.6) (2001–05). Our data can be underestimated because some patients could have skipped the local center. This emphasizes that the results, except for Sardinia, are comparable to Italian literature data. They confirm that this territory is a high risk area for MS. There is also an indirect indication against a latitude gradient for MS.     

Steadiness of amyotrophic lateral sclerosis in the province of Parma, Italy, 1960–1990

A clinical and epidemiological study on amyotrophic lateral sclerosis (ALS) was conducted in the province of Parma, Italy, from 1960–1990. A total of 121 cases were collected from hospital records. The average annual incidence was 0.98 per 100000 inhabitants, with a male/female ratio of 1.1. Age-specific incidence was maximal in the age group 60–69 years. No difference between rural and urban areas was found. Prevalence on October 26th, 1981 was 2.5 per 100000. Mean age at onset was 60 years, with no significant sex difference. Mean duration of the disease was 30 (sd 21.4) months. Bulbar forms were significantly (p<0.05) shorter than conventional forms, with a mean duration of 23.4 (sd 21.4) months. Age at onset did not influence prognosis. A comparison of three decades was made, to verify whether possible variations of the disease had occurred with time. From our data a definite stability was found in such epidemiological parameters as incidence, prevalence, mean duration and mortality of ALS in the period.     

Epidemiology of multiple sclerosis in northern Greece

A total of 638 new cases of multiple sclerosis (MS) (365 females, 273 males) were found from 1970-1984 in northern Greece (Macedonia and Thrace); the average annual incidence rate was 1.79 per 100,000 inhabitants with increasing incidence from 1980-1984. A total of 729 people living in northern Greece suffered from MS on December 31, 1984 (prevalence rate 29.5 per 100,000 inhabitants). No difference was found between urban and rural areas. No difference from the international standards was found for sex incidence. The study confirms the quite high prevalence of MS despite the fact that northern Greece is in the intermediate risk zone.     

Effects of recombinant α-2b-interferon therapy in patients with progressive MS

The effects of systemic recombinant interferon-α-2b were studied in 6 carefully selected patients with progressive multiple sclerosis. 3.0 million IU were given as daily subcutaneous injections for 6 months, 5 patients showed worsening disability, and in 4 of them new or enlarged lesions were detected in MRI. In one patient no change in disability was found; his MRI showed regressed changes. The mean progression index during the treatment was significantly higher (p < 0.02) than during the previous 2 to 3 years' period of continuous progression. The frequency of peripheral blood natural killer (CD16 +) cells declined significantly 3 months during the treatment, but returned to the pretreatment values after termination the treatment. An increase of intrathecal IgG synthesis and oligoclonal bands was demonstrated in 4 and 3 patients, respectively. Our experience suggests that long-term recombinant IFN-α-2b treatment may activate the immunological process of MS.     

Serial study of neuropsychological performance and gadolinium-enhanced MRI in MS

Many multiple sclerosis patients show cognitive decline, although no definite correlation between brain demyelination at MRI and neuropsychological performance has been found so far. We submitted a group of nine relapsing-remitting, mildly disabled patients to both serial gadolinium-DTPA enhanced MRI and neuropsychological evaluation in a follow up period of three months. Despite the great variability in acute lesions' load, no overall decline in test, performance was found. Furthermore, in selected cases whose test scores declined at follow up, no concordance with the new lesion load was found.     

Multiple sclerosis incidence in the era of measles‐mumps‐rubella mass vaccinations

Background – Viral childhood infections may be involved in the multiple sclerosis (MS) pathogenesis. Following national Swedish vaccination programs, measles sharply declined in the 1970s, and measles, mumps, and rubella were virtually eliminated in cohorts born from 1981. Objectives – To examine whether the vaccination induced reduction in these infections influences the MS incidence. In addition, the public health aspect justified an early evaluation of beneficial as well as harmful effects of mass vaccinations. Materials and methods – From an incidence material of 534 MS patients, born 1959–1990, we selected one unvaccinated cohort and four cohorts, each corresponding to a vaccination program (MS patients = 251). Results – With the ability to detect a decrease by 30–35%, and an increase by 37–48% in the MS incidence in the first three cohorts, we found no vaccination related MS incidence changes. The background MS incidence showed a significant gradual age dependent increase. Conclusions – While the present follow‐up provided limited power in the last cohort, there is no evidence as yet that the radical decline in three viral infections influenced the MS incidence. However, the increasing background MS incidence of unknown cause may have concealed a reduction in MS risk associated with mass vaccinations.     

Epidemiology of multiple sclerosis: incidence and prevalence rates in Denmark 1948–64 based on the Danish Multiple Sclerosis Registry

The Danish Multiple Sclerosis Registry (DMSR) is a national register based upon the ethnically homogeneous Danish population of about 5 millions. The DMSR was founded in 1956 following a nationwide Danish prevalence survey of MS in 1949 and a continuous registration of incident cases of MS since January 1, 1948. Included in DMSR are all Danish cases of MS (or suspicion of MS) diagnosed by a neurologist or a department of neurology. The sources of notification are the 22 neurological departments in Denmark, the National Patient Registry, the neuropathological departments, the Registry of Causes of Death, and, up to 1975, the Disablement Insurance Court. Notified cases which do not comply with the standardized diagnostic criteria of the DMSR are excluded. An estimate of the completeness of the DMSR is 90-95% and the validity is around 94%. Age- and sex-specific incidence rates of MS for the interval 1948-64 are presented. The crude annual incidence rate of MS in Denmark was in the year 1948-64 4.42 per 100,000 population, 22% higher in females than males. There was a significant geographical variation of incidence rates and a significant downward trend in incidence rates during the interval, whereas the prevalence rates showed a slight increase.     

Multiple sclerosis in Oslo, Norway: prevalence on 1 January 1995 and incidence over a 25-year period

The Oslo Multiple Sclerosis (MS) Registry was established in 1990, and this is the first report on the prevalence and incidence of MS in the city of Oslo, Norway. The prevalence rate of definite MS on 1 January 1995 was 120.4/10(5). Inclusion of patients of native Norwegian ancestry only and exclusion of non-Norwegian immigrants yielded a prevalence rate of 136.0/10(5). A similar prevalence rate (136.5/10(5)) was found when patients and immigrants from the other Nordic countries (Finland, Sweden, Denmark) were included. Segregation of the native Norwegian patients according to the counties where they were born showed no significant differences except for a disproportionate increase of patients born in the inland county of Oppland. A total of 794 cases were resident in Oslo at the time of a diagnosis of definite MS in the period 1972-99. The crude average annual incidence rate for each 5-year period, between 1972 and 1996, increased significantly from 3.7/10(5) in the 1972-76 to 8.7/10(5) in the 1992-96 period. The increase was more marked in relapsing-remitting (RR) than in primary progressive disease and in female cases.     

Accuracy of self-assessment of the minimal record of disability in patients with multiple sclerosis

We tested the validity of a self-administered version of the minimal record of disability (MRD) for multiple sclerosis (MS) by measuring the agreement level between patients' self-assessment and neurologists' indipendent ratings. 96 MS patients and 4 neurologists took part in the experiment; the agreement level was measured in terms of the intraclass correlation coefficient (ICC). On the Kurtzke functional system (FS) the ICC ranged from 0.26 in the sensory to 0.69 in the pyramidal function; a high concordance (ICC = 0.84) was found on the expanded disability status scale (EDSS). The ICC values were above 0.70 for most of the incapacity status scale (ISS) and environmental status scale (ESS) items. A modified, self-administered version of the MRD may represent a reliable instrument for obtaining a comprehensive profile of patients' abilities.     

A possible spatial and temporal cluster of multiple sclerosis in the town of Linguaglossa,Sicily

We carried out an epidemiological survey to determine prevalence and incidence of multiple sclerosis in the little town of Linguaglossa in the Province of Catania. We calculated prevalence rate as point prevalence at 1 January 2001 and incidence during 1991–2000.We studied the frequency of multiple sclerosis in the community of Linguaglossa in a population of 5,422 inhabitants in the 2001 census. The primary sources for the case ascertainment were the general practitioners of Linguaglossa, the local Italian Multiple Sclerosis Association and the neurological departments, Multiple Sclerosis Centers and private neurologists of the province of Catania. We considered as prevalent and incident cases all patients who satisfied the Poser’s diagnostic criteria. We detected 11 patients with multiple sclerosis who had had the onset of disease on prevalent day (P.D.). The onset–adjusted prevalence rate was 203/100,000 (95% CI 107–352).Prevalence was higher in women (247/100,000) than in men (154/100,000). From 1991 to 2000, 10 subjects with MS had clinical onset of disease. The mean annual incidence risk was 18.2/100,000 (C. I. 95 % 5.9–42.5).Conversely in the same population prevalence on 1 January 1991 was 37/100,000 while the onset adjusted annual incidence risk during the previous decade (1981–1991) was 3.6/100,000. Prevalence and incidence rates of MS during the last decade in the little town of Linguaglossa are higher than those found in the same area during the previous ten years and also than those reported in other Sicilian and Italian surveys suggesting a possible cluster of MS.     

Motor neuron disease on Guam: temporal xcurrence, 1941–85

Using a case registry, we investigated the temporal occurrence of motor neuron disease (MND) on Guam. MND with onset during 1941–85 was documented in 434 Chamorros and 9 non-Chamorro migrants who had lived on Guam before onset. Increased median age at onset and decreased age-adjusted incidence rates (since the early 1960s) were observed for Chamorros of both sexes. Our evidence about MND on Guam is consistent with: 1) The latent period duration has varied from years to decades; 2) With time, the exposure period or latent period, or both, have lengthened; 3) The high risk of acquiring the condition has been reduced since, at least, the early 1950s, and the most recent years of meaningful risk were the early to middle 1960s; 4) The critical age for acquiring the condition is in adolescence and adulthood; 5) Change of environment from Guam to overseas during childhood resulted in decreased risk of acquiring the condition.     

The epidemiology of eating disorders in Fyn County, Denmark, 1977-1986.

The occurrence of anorexia nervosa and bulimia in Fyn County, Denmark is described. Incidence was estimated from national and local registers. The DSM-III-R criteria of one or both eating disorders were met by 104 patients. The incidence of anorexia nervosa for females 10 to 24 years of age was 11.0 per 100,000 per year. In the same population, the incidence of bulimia was 5.5 per 100,000 per year. Prevalence was estimated from questionnaires to and interviews with general practitioners. There were 193 cases; the prevalence of anorexia nervosa was estimated at 1:780 (patient years/total population years), and the prevalence of bulimia at 1:1480, in the high-risk population: females 15-19 years of age. Sixty percent of the anorexia nervosa patients, but only 30% of the bulimia patients, were admitted to hospital; this is an important difference in regard to estimation of occurrence from registers.     

Multiple sclerosis in Gijon health district, Asturias, northern Spain

The objective of this study was to ascertain the prevalence and incidence of Multiple Sclerosis (MS) in a population of 33,775 in two primary health care centres in the sanitary district of Gijon, Asturias, northern Spain. Many information sources were used but the unique advantage of Gijon was that the city has a centralized computerized register of all diagnoses made for all consultations in the clinics and hospitals in the area. The HLA distribution in the population was already known and the Poser classification of MS was used. The crude MS prevalence was 65/100,000, a similar prevalence to that found in southern and eastern Spain, Sicily and Greek-speaking Cyprus. The mean incidence was 3.7/100,000 per year. The study demonstrated the advantage of a centralized and computerized medical recording system and demonstrates that northern Spain is a moderatelv high or medium MS risk zone.