Case-control study of completed ischemic stroke in the Parsis of Bombay: a population-based study

All eligible adult cases of completed ischemic stroke (N = 112) derived from a prevalence survey of the Parsi community in Bombay, India, served as the basis of a case-control study of risk factors. The stroke morbidity rate in this group was similar to that reported for North America. A control subject free of stroke was selected randomly from the same population and matched to each case by age and sex. Information was obtained on various risk factors. Hypertension, both by history (odds ratio = 10.8) and by examination (odds ratio = 2.1), had a statistically significant association with stroke (p less than 0.01). This is one of the first community-based case-control studies of stroke in a large developing country.     

Prevalence of multiple sclerosis in British Columbia

A province wide prevalence study on multiple sclerosis (MS) was conducted in British Columbia (B.C.). The prevalence date was July 1, 1982. The major portion of this study was a review of all the files of neurologists practicing in B.C. as this was judged to be the most accurate source for identifying MS patients. 239,412 neurologists' files were hand searched by one researcher using modified Schumacher criteria for classification. Other sources used during the study for identifying MS patients were the MS Clinic, general practitioners, ophthalmologists, urologists, specialized facilities such as long term care facilities and rehabilitation centres, and patient self-referrals. A total of 4,620 non-duplicated cases were identified and classified. 4,112 of these (89%) were classified according to information contained in neurologists' records. The prevalence estimate for definite/probable MS in B.C. was 93.3/100,000 population. This increased to 130.5/100,000 population if possible MS and optic neuritis were also included. These rates are among the highest reported in Canada or elsewhere. The cooperation of B.C. neurologists made this study unique in its scope and accuracy of diagnosis.     

Prevalence of multiple sclerosis in Rochdale.

The prevalence of multiple sclerosis in the Rochdale Metropolitan Borough in the north east of Greater Manchester has been established. Case ascertainment was partly prospective via a neurological register from 1979 and by contact with general practitioners, therapists, and social services. On prevalence day, 1 January 1989, 254 patients with multiple sclerosis were living in Rochdale. The overall prevalence was 122/100,000 population and 96/100,000 population for probable cases only. The peak rate for women aged 35 to 44 years was 437/100,000 population and for men aged 45 to 54 years 221/100,000. Familial multiple sclerosis was present in 10.8% of families. In this, the first study in north west England, the prevalence of multiple sclerosis in Rochdale is similar to that in southern England and Wales but lower than that in Scotland.     

Prevalence of multiple sclerosis in Isfahan, Iran

BACKGROUND: The prevalence of multiple sclerosis (MS) shows considerable variability all over the world. According to Kurtzke, Iran is considered to have a low prevalence. OBJECTIVE: To estimate the period prevalence and risk factors of MS in Isfahan, central part of Iran. METHODS: A cross-sectional case register study conducted between 2004 and 2005. In the province of Isfahan, Iran, all patients known to have definite MS during 2004 and 2005, being alive and resident within Isfahan as well as being a member of the Isfahan MS Association were included in the study. Demographic and case-related information was recorded. 1,391 definite MS patients (308 men and 1,083 women) from the Isfahan MS Association, Iran, have been identified. The disease was confirmed using clinical information and MRI findings by a neurologist and radiologist. The patients were evaluated by interview and a questionnaire. Population data were obtained from the year 1999 Iran Census. The mean (SD) age of the participants was 32.5 (9.3) years with a mean (SD) duration of the disease of 6.4 (5.1) years for men and 6.9 (5.3) years for women. RESULTS: The period prevalence of MS was 35.5 per 100,000 [95% confidence interval (CI) 33.6-37.3] in a population of 3,923,255, with a higher rate in women than men [54.5 (95% CI: 51.1-57.8) for women and 14.9 (95% CI: 13.3-16.6) for men]. The female/male ratio was 3.6 (95% CI: 3.2-4.1). The direct age-adjusted period prevalence was 59.5 per 100,000 (95% CI: 44.8-75.2) for women and 17.0 per 100,000 (95% CI: 8.9-25.1) for men. MS rates were highest among 30- to 39-year-olds and decreased with increasing age. Sensory and visual disturbances were the most common initial presentations with a prevalence of 51.1% (95% CI: 48.4-53.7) and 47.0% (95% CI: 44.4-49.7), respectively. CONCLUSION: Isfahan could be considered as an area with a medium to high risk of MS. This is in sharp contrast with the gradient hypothesis.     

Multiple sclerosis is prevalent in the Zoroastrians (Parsis) of India

Using Schumacher's classification, we determined the prevalence rate of clinically definite multiple sclerosis (MS) in the distinct but tiny Zoroastrian (largely Parsi) community in the adjacent cities of Bombay (latitude, 18.55 degrees) and Poona (Pune). On prevalence day, 16 clinically definite cases of MS were counted, 14 in Bombay and 2 in Poona, from a total Zoroastrian population of 50,053 and 3,399, respectively. The crude prevalence ratio was 26 per 100,000 for Bombay and 58 per 100,000 for Poona. The age-adjusted prevalence ratio for Bombay was 24 per 100,000, with 95% confidence limits of 13.1 to 40.3. These are much higher than the low rates believed to be prevalent in India, and are comparable with those found in parts of Europe and the United States.     

Prevalence of multiple sclerosis in Belgrade, Yugoslavia

OBJECTIVES: To estimate the distribution of multiple sclerosis in the Belgrade population. METHODS: All persons who were affected and/or died from multiple sclerosis (Poser's criteria), with residence in the Belgrade region had been collected from January 1, 1985 to December 31, 1996. Prevalence was adjusted by direct method, using world population. RESULTS: From 1985 to 1996, 823 patients were suffering from multiple sclerosis. Sex ratio was 1:1.9. The mean age at onset was 32.2 +/- 9.8 years. A relapsing-remitting course of multiple sclerosis was reported in 50.7% patients, secondary progressive in 36.4%, patients, and primary progressive in 12.9% patients. On December 31, 1996, age-adjusted prevalence of multiple sclerosis in Belgrade was 41.5/100,000, 28.2/100,000 for males, and 54.1/100,000 for females. During the period studied, statistically highly significant increasing trend of multiple sclerosis prevalence was observed (P = 0.0001). CONCLUSIONS: According to findings presented in this study, Belgrade is an area with high prevalence of multiple sclerosis.     

Prevalence of multiple sclerosis in Valladolid, northern Spain

The aim of this study was to ascertain the prevalence of multiple sclerosis (MS) in a northern Spanish region and to compare it with that from the most recent epidemiological studies in the country. MS prevalence was studied for a period of 2 years using multiple sources of information in the province of Valladolid, with a sample comprising a total population of 92,632. Patients were classified according to the Poser criteria. The crude prevalence of definite and probable MS was 58.3 per 100,000 (95% confidence interval: 43.7–75.7). The same methods have been used in ascertaining similar prevalence rates in Vélez-Málaga, Osona, and Gijón and a slightly lower rate in Teruel. Our survey confirms Spain as a high-risk area for MS, with prevalence rates over 50 per 100,000. Received: 4 March 1998 Received in revised form: 13 May 1998 Accepted: 10 June 1998     

Prevalence of sleep problems in individuals with multiple sclerosis

BackgroundSleep disturbance in multiple sclerosis has received little research attention despite the potential influence it may have on disease impact.ObjectiveTo estimate the prevalence of sleep disorders in a large community sample of individuals with multiple sclerosis.MethodsA cross-sectional self-report survey of 1063 persons with multiple sclerosis. Sleep was assessed using the Women's Health Initiative Insomnia Rating Scale and Medical Outcomes Study Sleep measure.ResultsThe prevalence of sleep problems in multiple sclerosis is significantly higher than in the general population or other chronic diseases and may affect women with multiple sclerosis more than men.ConclusionSleep disturbance should routinely be evaluated in patients with multiple sclerosis and new interventions developed.     

Prevalence of multiple sclerosis in Gypsies and Bulgarians.

There are occasional reports about the low prevalence of multiple sclerosis among Gypsies. To verify these reports of low prevalence of multiple sclerosis among Gypsies compared to the white population in Bulgaria, an epidemiological study was conducted in two small regions of Bulgaria. All patients with clinically or laboratory-supported, definite multiple sclerosis according to Poser's criteria were personally interviewed and examined. The study was begun on January 1, 1997 and March 31, 1998 was selected as prevalence day. For the white population, the prevalence ratio of multiple sclerosis per 100,000 population was 44.9 in the first region and 44.4 in the second. The prevalence of multiple sclerosis in Gypsies was found to be 19.1/100,000 in the first region and 18.4 in the second. It is concluded that multiple sclerosis is less common in Gypsies than in whites living in the same areas.     

Prevalence of multiple sclerosis in the province of Teruel, Spain

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. Received: 7 May 1996 Received in revised form: 17 September 1996 Accepted: 23 September 1996     

Prevalence of multiple sclerosis in the L'Aquila district, central Italy

OBJECTIVE: To estimate the prevalence of multiple sclerosis in the L'Aquila district, central Italy. METHODS: All available case sources were screened. Definite and probable cases of multiple sclerosis, classified according to the Poser criteria, were considered as prevalent cases. RESULTS: On the prevalence day, 31 December 1996, 158 patients (105 women and 53 men; ratio 2:1) affected by definite (n=131) or probable (n=27) multiple sclerosis were alive and resident in the L'Aquila district. Mean (SD) age was 38.4 (11.9) years (38.9 (11.7) years for women and 38.5 (12.3) years for men, p=0.9). The overall crude prevalence was 53.0/100 000 (95% confidence interval (95% CI)=45.4-62.0); 68.4/100 000 (95% CI=56. 5-82.8) in women, and 36.7/100 000 (95% CI=28.1-48.0) in men. The prevalence was similar (55.9/100 000) when standardised to the 1996 European population. Mean (SD) age at onset of multiple sclerosis was 29.4 (9.6) years and mean (SD) duration of the disease was 9.4 (7.4) years, without any significant difference between sexes. Mean age at onset was significantly higher in patients with the primary progressive than in those with the relapsing-remitting course (p=0. 0002, Scheffé's test). CONCLUSIONS: The prevalence found in the L'Aquila district gives support to the consideration of Italy as an area in which multiple sclerosis has been shown to have high prevalence at least in the populations that were surveyed recently.     

Prevalence of Epilepsy in the Parsi Community of Bombay

A door-to-door survey was carried out to screen a community of 14,010 people (Parsis living in colonies in Bombay, India) for possible neurologic diseases. High school graduates, social workers, and medical students administered a screening questionnaire that in a pilot survey had a sensitivity of 100% for identifying persons with epilepsy. Neurologists used defined diagnostic criteria to evaluate individuals positive on the screening survey. Sixty-six persons (43 males, 23 females) suffered from epilepsy (4.7 cases/1,000). Of those, 50 (34 males, 16 females) had active epilepsy (3.6 cases/1,000). The age-specific prevalence ratios remained fairly constant for each age group except for a small peak in the group aged 20-39 years for all epilepsy cases combined. Age-adjusted prevalence ratios were higher for males. The most common seizure type was partial (36 cases). The most frequently associated conditions were cerebral palsy and mental retardation. The majority of individuals were receiving medication as of prevalence day (47 cases).     

Prevalence of multiple sclerosis in First Nations people of Alberta

BACKGROUND: Multiple Sclerosis (MS) is reported to be uncommon among North American aboriginals despite frequent intermarriage with people of European ancestry, but few population-based studies have been conducted. The purpose of this study was to determine the prevalence of MS among First Nations aboriginal people in Alberta, Canada compared to the general population. METHODS: All hospital in-patient and physician fee-for-service records between 1994 and 2002 where a diagnosis of MS was mentioned were extracted from government health databases in the province of Alberta. First Nations people can be identified since the federal government (Health Canada) pays health care insurance premiums on their behalf. Multiple Sclerosis prevalence per 100,000 population for both First Nations people and the general population of Alberta were calculated for each year during this time span. RESULTS: Among First Nations in Alberta, MS prevalence was 56.3 per 100,000 in 1994 and 99.9 per 100,000 in 2002, an increase of 43.6%. In 2002 prevalence was 158.1 and 38.0 for females and males respectively, a female to male ratio of 4.2:1. Multiple Sclerosis prevalence among the general population of Alberta was 262.6 per 100,000 in 1994 and 335.0 per 100,000 in 2002, an increase of 21.6%. In 2002 prevalence was 481.5 and 187.5 for females and males respectively, a female to male ratio of 2.6:1. Peak prevalence for both First Nations and general population females in 2002 was age 50-59, also 50-59 for both First Nations and general population males. CONCLUSION: While MS prevalence in First Nations people is lower than in the general population of Alberta, it is not rare by worldwide standards.     

Prevalence and incidence of multiple sclerosis in Catania, Sicily

OBJECTIVE: An epidemiologic survey was conducted to determine the prevalence and incidence of MS in the city of Catania, Sicily, Italy. Prevalence rate was calculated as point prevalence at January 1,1995, and incidence during 1974 to 1995. METHODS: The authors studied the frequency of MS in the community of Catania in a population of 333,075 inhabitants according to the 1991 census. The primary sources for the case ascertainment were the neurologic and motor rehabilitation departments, the MS Center, the Italian MS Association, private neurologists, and family doctors. All patients who satisfied the Poser criteria for clinically definite MS, laboratory-supported definite MS, clinically probable MS, and laboratory-supported probable MS were considered prevalent and incident cases. RESULTS: One hundred ninety-five patients with MS who had had the onset of disease on prevalence day in a population of 333,075 inhabitants were detected. The prevalence rate was 58.5 per 100,000 (95% CI 50.7 to 67.5). Prevalence was higher in women (62.0/100,000) than in men (54.8/100,000). The age-specific prevalence showed a peak in the group aged 35 to 44 (145.1/100,000). From 1975 to 1994, 170 subjects with MS had the clinical onset of the disease. The mean annual incidence was 2.3 per 100,000 (95% CI 2.0 to 2.6). Age-specific incidence showed a peak in the group aged 25 to 34 (6.32/100,000). Incidence for 5-year intervals increased from 1.3 during 1975 to 1979 to 3.9 during 1990 to 1994. CONCLUSIONS: These prevalence and incidence rates are close to those reported in other similar surveys carried out in Italy and southern Europe.