The current neurologic burden of illness and injury in the United States

Estimates of the need for neurologists must be based ultimately on the frequency of neurologic disease. Community-based population surveys for diseases or injuries that have come to medical attention provide annual incidence rates per 100,000 population, point prevalence rates per 100,000, and average duration in years. For 61 disorders, including for 8 only those fractions that were thought to require neurologic attention, the annual incidence rates summed to 2500 per 100,000 or 2.5% of the population. For 55 of these conditions, including for 6 only the neurologic fraction and excluding all mental retardation, blindness, deafness, or psychosis, the point prevalence rates summed to 9500 per 100,000 population. Even if we also excluded all headache, all trauma, all alcoholism, and all vertebrogenic pain states, 3.6% of the general population at any one time should be under neurologic care. Substracting all these exclusions from the incidence rates similarly leaves more than 1 person in every 100 who each year will have a new neurologic disorder that requires the attention of a physician competent in clinical neurology.     

Isolation and characterization of bacteriophage BCJA1, a novel temperate bacteriophage active against the alkaliphilic bacterium, Bacillus clarkii

A previous epidemiological study on myasthenia gravis (MG) in Sardinia indicated a prevalence rate of 4.5 per 100,000 population and an incidence of 0.25 per 100,000 population in the period 1958-1986. This study, however, investigated the entire Sardinian population (about 1,500,000) and the reported rates are likely to be underestimated. Because the use of a very large population has been found to cause major bias in case finding, the present study was designed to overcome this bias by determining the prevalence and incidence of MG in a well-defined area of Northwestern Sardinia, with a population of about 270,000 (1991 census). Potential MG cases were ascertained using all possible medical sources. The diagnosis of MG was based on the clinical, neurophysiological and conventional pharmacological findings (Tensilon test, response to anticholinesterases). On prevalence day (December 31, 1994) 29 MG patients were living in the study area (17 women and 12 men). Since the total population on prevalence day was 268,926 (137,284 women and 131,642 men), the calculated prevalence was 11.1 per 100,000 population (12.4 women and 9.9 men). The present study shows that the risk of MG in Sardinia is higher than previously suggested. The risk, however, is not significantly different from that found in other comparable Italian and European areas. It contrasts with what has been found for other autoimmune diseases such as multiple sclerosis and insulin-dependent diabetes mellitus in Sardinians, both showing frequencies up to 3-5 times higher than in the rest of Italy.     

Prevalence of juvenile chronic arthritis and familial Mediterranean fever in Turkey: a field study

OBJECTIVE: To investigate the prevalence of juvenile chronic arthritis (JCA), familial Mediterranean fever (FMF), and Beh?et's disease in Turkish children through a field survey. METHODS: The field survey was based on cluster centering with 2 level strata. A total of 46,813 children were screened. For the diagnosis of chronic arthritis and Beh?et's previously suggested criteria were used. We have developed criteria for the diagnosis of probable FMF. Children previously diagnosed to have these diseases were also defined and included. RESULTS: JCA was found in 6.4/10,000. 2.8/10,000 children were previously diagnosed as FMF (minimum phenotype frequency). Together with the probable diagnosis of FMF, the prevalence increased to 9.3/10,000. The findings were also compared with those of our center. None of the 46,813 children had Beh?et's disease. CONCLUSION: The prevalence of chronic arthritis is similar to the other childhood populations reported. However, FMF has a very high prevalence.     

Incidence of IDDM in children living in Puerto Rico. Puerto Rican IDDM Coalition

OBJECTIVE: To determine incidence, geographic distribution, and seasonal variation of IDDM in children 0-14 years of age living in Puerto Rico. Because these data have been collected through the infrastructure of the World Health Organization's DiaMond project, these results are directly comparable with incidence data from other population worldwide involved in this study. RESEARCH DESIGN AND METHODS: Beginning in 1990, new cases of IDDM were registered retrospectively from 1985 and prospectively to 1994 by review of medical records from island hospitals. Included in the hospital registry are 1,527 cases of IDDM. Validation of the primary source was by three secondary lists of cases obtained through diabetic camps, surveys of schools, and a government registry. Long linear modeling (capture-recapture) was used to correct incidence. RESULTS: Mean incidence of IDDM from 1985-1994 was 18.0 cases/100,000 children per year (95% CI 17.6-18.3). There was a slight female rather than male predominance: 51% of the cases were girls, and 49% were boys. Although Puerto Rico has marked variation in rainfall, altitude, and genetic markers, no significant differences are found in the incidence rates of different areas or seasons of the island. CONCLUSIONS: This registry of Puerto Rican children is the largest IDDM registry of minority children in the U.S. The results of this study indicate that the annual incidence of IDDM of children living in Puerto Rico is higher than the incidence of other multiracial ethnic groups living in the U.S.     

Age-specific incidence and prevalence rates of treated epilepsy in an unselected population of 2,052,922 and age-specific fertility rates of women with epilepsy

BACKGROUND: There are no data on prevalence or incidence of treated epilepsy, and no data on fertility of women with epilepsy from an unselected UK population. METHODS: We used the General Practice Research Database to ascertain the incidence and prevalence of people with treated epilepsy in an unselected population of 2,052,922 people in England and Wales, and also age-specific fertility rates. We defined period prevalence of treated epilepsy as the number of people with epilepsy taking an antiepileptic drug per 100,000 people during 1995. The incidence of treated epilepsy was defined as the number of new cases of treated epilepsy per 100,000 people during the same period. We calculated fertility rates among women with treated epilepsy between 1991 and 1995 and compared these rates with the population rates for England and Wales in 1993. FINDINGS: The period prevalence of treated epilepsy in 1995 was 5.15 per 1000 people (95% CI 5.05-5.25). The prevalence was lower in children (age 5-9 years 3.16 [2.86-3.48]; 10-14 years 4.05 [3.70-4.42]), and higher in older people (65-69 years 6.01 [5.50-6.57]; 70-74 years 6.53 [5.97-7.14]; 75-79 years 7.39 [6.73-8.11]); 80-84 years 7.54 [6.78-8.39]; 85 years and older 7.73 [6.98-8.66]). The incidence of treated epilepsy was 80.8 per 100,000 people (76.9-84.7). The incidence was lower in children (5-9 years 63.2 [50.5-79.1]; 10-14 years 53.8 [42.4-68.3]) and higher in older people (65-69 years 85.9 [68.5-107.3]; 70-74 years 82.8 [65.0-105.2]; 75-79 years 114.5 [116.9-179.2]; 80-84 years 159 [125.2-202.6]; > or = 85 years 135.4 [100.4-178.7]). Fertility was lower among women with treated epilepsy, with an overall rate of 47.1 livebirths per 1000 women aged 15-44 per year (42.3-52.2), compared with a national rate of 62.6 in the same age-group. The standardised fertility ratios were significantly lower between the ages of 25 and 39 years in women with epilepsy (p<0.001). INTERPRETATION: Compared with previous studies, we found that the incidence of epilepsy was higher in elderly people and lower in children. The prevalence rates also increase with age. Women aged 25-39 years with treated epilepsy have significantly lower fertility rates than those in the general population. Research is needed to identify any potentially preventable causes for the low fertility rates.     

Prospective study of bacterial meningitis in North East Thames region, 1991-3, during introduction of Haemophilus influenzae vaccine

OBJECTIVE: To describe the epidemiology of primary bacterial meningitis in the North East Thames region over a three year period before and during the introduction of the vaccine for Haemophilus influenzae type b. DESIGN: Analysis of information on cases of primary bacterial meningitis identified by microbiology laboratories in the region, with collection of case data by questionnaire. MAIN OUTCOME MEASURES: Annual incidence rates for types of meningitis according to age and ethnic group. RESULTS: The annual incidence rates for the three major causes of bacterial meningitis in the general population were 1.9/100,000 for Neisseria meningitidis, 1.6/100,000 for Haemophilus influenzae before vaccination, and 1.0/100,000 for Streptococcus pneumoniae. Higher rates of H influenzae meningitis were found in Asians compared with white people (3.6/100,000 v 1.5/100,000, P = 0.01). As a result of the vaccine programme introduced in October 1992 the number of cases of H influenzae meningitis in children under 5 years has fallen by 87%. CONCLUSIONS: Bacterial meningitis is a serious problem especially in preschool children. There are differences in the incidence of some causes of bacterial meningitis in different ethnic groups; with H influenzae type b being significantly more common among black and Asian people than among white people. The immunisation programme for H influenzae type b in the North East Thames region has been successful in reducing the incidence of this type of meningitis in Asian and white populations. The numbers were too small to evaluate in the black population.     

The release of a coronary vasodilator metabolite from the guinea-pig isolated perfused heart stimulated by catecholamines, histamine and electrical pacing and by exposure to anoxia

The results of surveys and inquiries to identify autistic children, carried out in England and Wales, the U.S.A. and Denmark, are compared. Three studies, in each of which either a total population of children or a wide range of handicapped children was screened, using case-note inspection and interviews, all estimated the prevalence of the autistic syndrome to be between four and five children per 10,000 aged under 15 years. Inquiries that counted diagnosed cases only or that relied upon local authority records produced much lower prevalence rates for the autistic syndrome. The reasons for this are examined, and the implications for prevalence studies of handicapping conditions are discussed.     

Lights and shadows on the molecular diagnosis of hepatitis C

We undertook an epidemiologic study to ascertain the prevalence of multiple sclerosis (MS) in the Sanitary District of Calatayud, in the north-east of Spain. METHODS: The study was performed from October 1990 to July 1996. The total number of residents in the area was 58,591. An extensive search was carried out to identify all cases of known or suspected MS through general practitioners and specialists, sanitary authorities in the area, the reference hospital, the Spanish Multiple Sclerosis Society, the newspaper and radio. RESULTS: April 1, 1995 was chosen as prevalence day. The crude prevalence rate for the area was 58 per 100,000 (95% CI: 39-78). The approximate annual incidence rate was 2.6/100,000 (1980-1989). CONCLUSIONS: This study and others conducted recently in Spain show that MS is more prevalent than was previously thought and afflicts at least 53-65 per 100,000 population.     

Incorporating auxiliary variables into probability sampling designs

There have been few reports about the frequency of multiple sclerosis (MS) in Spain. We undertook a prevalence study in the province of Teruel, which is served by two hospitals as referral centres for a population of 143,680. We found a total of 46 patients who fulfilled Poser's criteria for clinically definite or probable MS with a prevalence rate of 32/100,000 [95% confidence interval (CI): 22.8-41.3]. The prevalence rates for males and females were 23.5 (95% CI: 12.3-34.7) and 40.6 (95% CI: 25.8-55.4) respectively. We found an incidence rate of 2.2/year per 100,000 in the last 5 years. The sex ratio (females/males) was 1.7. The mean age on prevalence day was 40.6 years (range: 15-76). The clinical course was relapsing-remitting in 82% of patients, progressive in 9% and secondary progressive in the other 9%. The mean EDSS score was 3.73 (range: 1-8.5). Our results confirm the hypothesis that Spain is an area at high risk for MS.     

Prevention and control of hepatitis B virus infection in Singapore

Hepatitis B virus (HBV) accounted for 24% to 54% of the reported acute viral hepatitis cases in Singapore from 1982 to 1996. The prevalence of HBV infection, as indicated by the presence of markers of HBV, increased from 9.3% in children below 5 years of age to 54.6% in adults above 55 years. The overall hepatitis B surface antigen (HBsAg) prevalence was 5.7% for males and 3.4% for females, with the highest rate among the Chinese. About 39% of the HBsAg carriers were hepatitis B 'e' antigen positive. The main mode of transmission during the first year of life was perinatal, with 43% of the babies born to HBsAg-positive mothers developing the carrier state. Horizontal transmission within the infected household was significantly associated with sharing of personal and household articles. Based on the findings of seroprevalence surveys in various population groups and clinical trials on the safety, immunogenicity and efficacy of various doses and schedules with the plasma-based and yeast-derived hepatitis B vaccines in newborn babies, a national childhood hepatitis B vaccination programme was formulated and implemented in phases, starting with babies born to carrier mothers on 1 October 1985 and finally extending to all newborns on 1 September 1987. The hepatitis B prevention and control programme has been successful. During the period 1994 to 1996, more than 90% of children completed the full schedule of immunisation by below one year of age, and 85% had evidence of vaccination at school entry at age six. Follow-up of 2 cohorts of vaccinated children showed that perinatal transmission has been reduced by 80% to 100%. Horizontal transmission has also declined through other public health measures. The efficacy of the hepatitis B vaccine and the adequacy of reduced doses in the long-term protection of chronic carrier state have been shown in children and adults. The incidence of acute hepatitis B has declined from 10.4 per 100,000 in 1985 to 4.8 per 100,000 in 1996. There is a noticeable reduction in HBsAg prevalence in selected population (school children, national servicemen and antenatal women). The age-standardised incidence rate of primary liver cancer among males had also dropped from 27.8 per 100,000 per year during 1978 to 1982 to 19.0 per 100,000 per year during 1988 to 1992.     

Prevalence and clinical aspects of tuberculosis in children and adolescents in the Primorsk Region

The analysis of epidemiological trends in tuberculosis registered for 13 years in children and adolescents living in the Primorsky Region of Russia discovered a trend to an increase of its incidence rate especially in girls and rural population. The morbidity of children aged 4-6, schoolchildren and adolescents aged 17 reached in 1993 137, 22.9 and 62.8 per 100,000 people, respectively. Tuberculosis of the respiratory organs occurred most frequently. In children tuberculosis of intrathoracic lymph nodes was encounted in 88.2% of new cases, in adolescents focal and infiltrative forms were recorded in 27 and 50.8%, respectively. Worsening of ecological and social situation in the region affected negatively immunological indices in the young population. This necessitates urgent measures to control spreading tuberculosis in the Far East of Russia.     

Incidence of neural tube defects in the Magdeburg administrative district

The Magdeburg Register of birth defects includes information on the incidence rate of neural tube defects (NTD) in the city of Magdeburg since 1980, and in the Regierungsbezirk (administrational district) since 1987. The average prevalence of NTD was 16.4 per 10,000 births in the city of Magdeburg, and 12 per 10,000 births in the surrounding counties. Besides of this significant difference between the city and counties, there are conspicuous variations from one year to the next. In 1987 the prevalence of NTD was about 27 per 10,000 births in the city of Magdeburg whereas the observed prevalence in the countryside was about 19 per 10,000 births. Different eating habits and/or increased teratogenic influences in the city may be considered as causes. In 1997 there was also a high rate of incidence of NTD in the city of Magdeburg--16.4 per 10,000 births. The incidence rate of NTD in the counties (about 10 per 10,000) births) is again lower than in the city. Because of these incidence rates, we may assume that the examined population is insufficiently protected by folic acid in the preconceptional stage.     

Epidemiology of multiple sclerosis in the county of Vestfold, eastern Norway: incidence and prevalence calculations

The county of Vestfold in the South-eastern part of Norway has undergone two incidence and prevalence surveys on multiple sclerosis. The prevalence of definite/probable MS on January 1, 1963 was 61.6/100,000. Based on the same diagnostic criteria, the present study reports a slight increase in prevalence to 86.4/100,000 on January 1st 1983. The average annual incidence was calculated for 5 years periods from 1953 to 1983. The time periods 1953-1962 and 1973-1977 showed age-adjusted incidence rates between 4.50 and 5.49/100,000 while the 10-year period 1963-1972 showed significantly lower rates. The fluctuating pattern of MS incidence and prevalence over time supports the view that MS is not a stable disease, and that exogenous factors are influencing the disease pattern.     

Beneficial effect of alpha-blocker on hemorheology in patients with essential hypertension

BACKGROUND: An increased prevalence of allergic diseases and atopic sensitization as assessed by skin-prick testing in children in West compared with East Germany has been reported. OBJECTIVES: This study was designed to evaluate whether such a difference is also present in adults, and if this can be shown when using a serological test for allergic sensitization. METHODS: Two large samples representative for all adults between 25 and 69 years of age were drawn in West (1991, n = 5313) and East Germany (1992, n = 2617). A serological test screening for IgE-antibodies to common aeroallergens (SX1) was performed. A questionnaire was used to assess the presence of clinical respiratory allergy, known possible risk factors for allergies and confounding variables. RESULTS: Allergic sensitization decreased with age. Significantly more subjects < 45 years of age had a positive allergy test in West as compared to East Germany. The prevalence of clinical allergy was also higher in West Germany. This difference was significant in younger adults and was independent of other risk factors identified. These additional risk factors encompassed younger age, higher educational level, male sex, and living in a community with more than 100,000 inhabitants. CONCLUSION: Sensitization to common aeroallergens as determined by a multiple allergen RAST test in adults below 45 years of age living in West Germany is increased compared to East Germany. This increase cannot be explained by genetic differences and is similar to the West to East decreasing gradient in allergies reported from studies in children employing skin-prick tests.     

Autopsies in children: are they still useful?

BACKGROUND: Juvenile chronic arthritis (JCA) is the commonest autoimmune rheumatic disease in childhood and presents different clinical subtypes. Juvenile chronic arthritis is considered to be of a polygenic nature and its genetic background is still under investigation. The clinical profile of JCA in the Greek population has not been studied completely. This study retrospectively analyzed the clinical and immunological features of JCA in Greek children presented between 1989 and 1994. Human leukocyte antigen (HLA)-positive or -negative associations in the different clinical subtypes were also detected. The findings of this study were correlated with those reported from other populations. METHODS AND RESULTS: Antinuclear antibodies (ANA) anti-ds DNA and anti-extractable nuclear antigen antibodies were estimated by immunofluorescent and ELISA assays. Human leukocyte antigen typing was performed by microlymphocytotoxicity, using immunobeads. The peak ages of JCA onset were between 2 and 5 years and also between 9 and 12 years. There was a high female predominance in pauciarticular and polyarticular groups. The most common disease was pauciarticular (58.7%) followed by systemic (25%) arthritis. The incidence of eye involvement was 12.5% and presented only in the pauciarticular group. Overall, ANA positivity was 53.7%, increasing to 90% in pauciarticular cases associated with chronic uveitis. In the early onset (EOPA) pauciarticular subtype, positive-HLA associations with alleles DR11 and DR8 were shown. In the late onset pauciarticular (LOPA) group only B27 allele was increased. CONCLUSIONS: The results of this retrospective study did not reveal major differences between JCA in Greek children compared with other Caucasian series.     

A secular increase in the incidence of juvenile diabetes mellitus

Data from a 1973 survey of diabetes mellitus among schoolchildren in Michigan have been analyzed to derive age-specific incidence and prevalence rates. The annual incidence of new cases of diabetes is approximately 20/100,000 children from age four through age 17, with the highest incidence rates at age nine through age 12. The prevalence rates to be expected, if the most recent incidence rates persist, are approximately 50/100,000 at age five, 150/100,000 at age ten, 270/100,000 at age 15, and 325/100,000 by age 18. The incidence rate of diabetes in Michigan children appears to have doubled between 1959 and 1972. Data from Erie County, New York, suggest that this secular trend has been evident since 1949, and data from Norway suggest that the trend could be noted 50 to 70 years ago.     

Prevalence, incidence, and characteristics of multiple sclerosis in Westlock County, Alberta, Canada

We report a prevalence study of multiple sclerosis (MS) in the town of Westlock and surrounding county of Westlock, in Alberta, Canada. The prevalence rate for clinically definite MS on January 1, 1991, was 200/100,000. The average annual incidence rates for patients living in the area at onset were 1.91/100,000 for 1950-1959, 2.85/100,000 for 1960-1969, 3.82/100,000 for 1970-1979, and 7.26/100,000 for 1980-1989. Forty-eight percent of the patients were relapsing-remitting. Sixty percent were still walking without assistance. The female-to-male ratio was 1.4:1. Mean current age was 47, age at onset 30, and duration of illness 18 years. The majority of patients (40%) experienced multiple symptom onset. Forty percent were of single ethnic origin (primarily British); the remainder were predominantly north European combinations. Twenty-four percent of patients reported another MS relative, six first-degree and one second-degree relative.     

Microtubules are responsible for the asymmetrical distribution of organelles in the oocytes of the hymenopteran, Chrysis ignita

To estimate prevalence and incidence of adult Still's disease in Japan, and to describe the epidemiological features of the patients, a nationwide epidemiological survey was conducted in 1994. The study consisted of two questionnaires which were distributed to the heads of the relevant departments, randomly sampled, in hospitals throughout Japan. Following major epidemiological findings emerged from the study: (a) The total annual number of patients treated for adult Still's disease was estimated as 1,100 in 1993 in Japan. The estimated crude prevalence among those aged 16 years or older were calculated as 0.73 and 1.47 per 100,000 population for males and females, respectively, with the corresponding crude incidence rate of 0.22 and 0.34. (b) The sex ratio (female to male) of the reported patients was 2.1. This female predominance might be specific to Japan, though additional surveys in other countries will be warranted. The mean age of the patients was 38.1 years, and female patients tended to be older than male ones; 50% of the female patients aged 40 years or older, while so did only 28% of the male patients.     

In vitro and in vivo antibacterial activities of AM-1155 in the fields of obstetrics and gynecology

OBJECTIVES: Until relatively recently southern Europe was regarded as having a medium to low multiple sclerosis prevalence, of about 20 or less per 100,000. However, recent studies in Sardinia, Sicily, continental Italy, Cyprus and Spain have yielded higher MS prevalence rates, between 32 and 102.6 per 100,000. We present the results of a prevalence study of MS in the municipality of M6stoles, central Spain. MATERIAL AND METHODS: To ascertain the prevalence of multiple sclerosis in M6stoles (195,979 inhabitants), an intensive study was undertaken using several sources of information. We used the Poser criteria in diagnosis. RESULTS: There were 85 patients (53 women and 32 men) classified as definite or probable, prevalence 43.4/100,000 (95% CI, 34.7 to 53.7). The incidence rate was 3.8/100,000/year (95% CI, 2.7 to 5.3) in the last 5 years. Mean age on prevalence day was 38.8+/-10.9 years. Mean age at onset was 31.7+/-9.3 years. Mean interval between initial symptoms and diagnosis was 1.7 years. Mean duration of disease was 7.6+/-6.1 years. Overall, 70.6% had a relapsing-remitting course, 18.8% had a primary progressive and 10.5% had a secondary progressive. Mean EDSS score was 2.7+/-1.9. CONCLUSION: The M6stoles study confirms the conclusions of previous smaller population studies that Spain is a moderately high or medium MS risk zone.     

Epidemiology of gastroschisis in China

OBJECTIVE: To study the clinical and epidemiologic characteristics of perinates with gastroschisis (GA) in China. METHODS: The birth defects monitoring program was undertaken in 945 hospitals from 29 provinces, cities and autonomous regions of China. Data about perinates including intrauterine death and stillbirth from 28 weeks of gestation to a period of 7 days after birth was collected through the medical records between October 1986 and September 1987. RESULTS: A total of 194 cases with GA was found in 1243284 perinates monitored. The incidence of GA in China varied from 0.4 to 3.4 with a mean of 1.6 per 10,000. The highest prevalence was in Shandong province (3.4/10,000) which was significantly higher than the average (P < 0.01). The prevalence of GA perinates with low birth weight was higher than that with normal birth weight (1.6 vs 0.6 per 10,000, P < 0.01), as well as that in the rural area higher than in the urban area (2.5 vs 1.1 per 10,000, P < 0.01). 70.6% of the cases with GA were accompanied with other major defects. The overall perinatal mortality rate (PMR) of GA was 91.8%. PMR of GA with other birth defects (95.6%) was significantly higher than that of GA only (82.5%, P < 0.01). Only 15% of GA were diagnosed before birth. CONCLUSIONS: GA was a serious malformation. Cases with GA had high PMR and low detection rates in prenatal diagnosis, and most often accompanied with multiple defects.