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     

Increasing frequency of multiple sclerosis in Padova,Italy: a 30 year epidemiological survey

OBJECTIVE: To determine the incidence and prevalence rates of multiple sclerosis (MS) and their temporal profiles over the last 30 years in the province of Padova (northeast Italy). BACKGROUND: In the early 1970s an epidemiological survey in the province of Padova showed a MS prevalence and incidence of 16/100 000 and 0.9/100 000 population, respectively; these figures are much lower than current estimates in other regions of Italy and Central Europe. METHODS: The population of the study area was approximately 820 000 (422 028 women, 398 290 men) in the 1991 census. All possible sources of case collection were used, but only clinically definite/probable and laboratory-supported definite/probable MS were considered in the analysis of incidence and prevalence trends from 1971 to 1999. RESULTS: On 31 December 1999, the crude prevalence rate was 80.5/100 000 (95% CI 70.3-90.7); prevalence was higher in women (111.1/100 000; 95% CI 99.0-123.1) than in men (49.7/100 000; 95% CI 41.3-58.1). This difference was significant (F/M = 2.43; z = 10.1, P < 0,00001); a rate adjusted for the European population was 81.4/100 000. On 31 December 1980 and on 31 December 1990 the estimated prevalence rates were 18/100 000 and 45.7/100 000, respectively. Thus, a fivefold increase in prevalence was observed from the 1970s. The mean annual incidence was 2.2/100 000 in the period 1980-89, 3.9 in the period 1990-94 and 4.2 in the period 1995 99. Thus, incidence increased more than fourfold from the 1970s through 1994 and remained quite stable in the last several years. Mean age at onset was 31.3 +/- 9.88 years. Mean diagnostic latency decreased significantly from 49.2 +/- 44.5 months in 1985 to 23.0 +/- 30.3 months in 1990, 12.9 +/- 15.61 in 1995 and 5.3 +/- 4.7 in 1999. CONCLUSIONS: The actual prevalence (80.5/100 000) and incidence (4.2/100 000) of MS in the province of Padova agree with the most recent epidemiological estimates/trends observed in other Italian and European areas, except for Sardinia and Scotland. The increase in both incidence and prevalence rates observed in much of this region over the last 30 years parallels the introduction of more sensitive diagnostic techniques and a highly significant decrease in diagnostic latency. These findings probably do not support a real increase in the frequency of MS in northeast Italy because recent estimates of incidence have increased only slightly (3.9 to 4.2, which is < 10% in five years) and increase in the prevalence rate was almost completely due to the accumulation of new incidence cases.     

Increasing incidence of multiple sclerosis among women in Lorraine, Eastern France

This study aims to describe the prevalence and incidence rates of multiple sclerosis (MS) in Lorraine, France, and its secular trend from 1990 to 2002. Cases were sourced from the regional network of MS healthcare workers in the Lorraine region and include all cases with definite or probable MS according to Poser's criteria. We identified 2718 patients with MS on 31 December 2004. The prevalence rate was 120/100,000 (95% confidence interval [CI]: 119-121). Between 1990 and 2002, the average age- and sex-adjusted annual incidence rate was 5.5/100,000 (95% CI: 4.4-6.6). During this same period, there was a significant increase in overall incidence in women but not in men. The mean age at MS onset, disability score five years after onset, number of relapses during the first five years, and proportion of first attack with sequelae or polysymptomatic symptoms were not significantly different between each annual cohort during the study period. The prevalence and incidence rates of MS we found in our study were higher than in previous studies in France. The increase in incidence of MS between 1990 and 2002, mostly in women, was not related to better ascertainment of patients with mild disability.     

Temporal trends of stroke in Valle d'Aosta, Italy. Incidence and 30-day fatality rates

The objective of this study was to evaluate temporal changes of stroke in an Italian community by comparing the present incidence rates with those reported in the same area for 1989. The two studies were conducted by the same research group and met almost all the criteria proposed for an “ideal” stroke incidence study. The annual incidence rate per 1000 inhabitants increased (p < 0.01) by 29% from 2.23 (95% CL, 1.96–2.50) in 1989 to 2.89 (95% CL, 2.58–3.20) in 1997. No statistically significant change was found when these rates were adjusted to the 1991 Italian population. The overall incidence rate was 2.40 (95% CL, 2.14–2.66) in 1989 and 2.65 (95% CL, 2.39–2.91) in 1997. The thirty-day case fatality rate declined dramatically (p < 0.001) from 31% (95% CL, 26– 36) to 20% (95% CL, 16–24) between 1989 and 1997. Ageing of the population and better identification of cases could explain the high incidence rate, whereas the decrease of fatality rate may be due to a general improvement in acute care and inclusion of milder cases. Received: 24 August 1999 / Accepted in revised form: 2 December 1999     

Psychosis and adults with intellectual disabilities

Objective To determine the point prevalence, incidence, and remission over a 2-year period of psychosis in adults with intellectual disabilities, and to investigate demographic and clinical factors hypothesised to be associated with psychosis. Method A population-based cohort of adults with intellectual disabilities (n = 1,023) was longitudinally studied. Comprehensive face-to-face mental health assessments to detect psychosis, plus review of family physician, psychiatric, and psychology case notes were undertaken at two time points, 2 years apart. Results Point prevalence is 2.6% (95% CI = 1.8–3.8%) to 4.4% (95% CI = 3.2–5.8%), dependant upon the diagnostic criteria employed. Two-year incidence is 1.4% (95% CI = 0.6–2.6), and for first episode is 0.5% (95% CI = 0.1–1.3). Compared with the general population, the standardised incidence ratio for first episode psychosis is 10.0 (95% CI = 2.1–29.3). Full remission after 2 years is 14.3%. Visual impairment, previous long-stay hospital residence, smoking, and not having epilepsy were independently associated with psychosis, whereas other factors relevant to the general population were not. Conclusions The study of psychosis in persons with intellectual disabilities benefits the population with intellectual disabilities, and advances the understanding of psychosis for the general population. Mental health professionals need adequate knowledge in order to address the high rates of psychosis in this population.     

Outdoor activities and diet in childhood and adolescence relate to MS risk above the Arctic Circle

Abstract Background A relationship between the latituderelated distribution of multiple sclerosis (MS) and exposure to sunlight has long been considered. Higher sun exposure during early life has been associated with decreased risk of MS. Objective Since Norway is an exception to the latitude gradient of MS prevalence, we tested here whether sunlight exposure or vitamin D-related dietary factors in childhood and adolescence are associated with the risk of MS. Methods Retrospective recall questionnaire data from 152 MS patients and 402 population controls born at and living at latitudes 66–71°N were analysed by means of conditional logistic regression analysis accounting for the matching variables age, sex, and place of birth. Results Increased outdoor activities during summer in early life were associated with a decreased risk of MS, most pronounced at ages 16–20 years (odds ratio (OR) 0.55, 95% CI 0.39–0.78, p = 0.001, adjusted for intake of fish and cod-liver oil). A protective effect of supplementation with cod-liver oil was suggested in the subgroup that reported low summer outdoor activities (OR 0.57, 95% CI 0.31–1.05, p = 0.072). Consumption of fish three or more times a week was also associated with reduced risk of MS (OR 0.55, 95% CI 0.33–0.93, p = 0.024). Conclusion Summer outdoor activities in childhood and adolescence are associated with a reduced risk of MS even north of the Arctic Circle. Supplemental cod-liver oil may be protective when sun exposure is less, suggesting that both climate and diet may interact to influence MS risk at a population level.     

Immunizations and risk of multiple sclerosis: systematic review and meta-analysis

The role of vaccinations in risk of developing multiple sclerosis (MS) or in risk of relapse has not been well established. The aim of this study was to estimate the effect of immunizations on risk of developing MS in adults as well as in subsequent risk of relapse. Systematic search for publications in MEDLINE (1966–January 2011), EMBASE (1977–January 2011) and the Cochrane Central Register of Controlled Trials (CENTRAL) (1961–January 2011). Both randomized clinical trials and non-randomized studies addressing the effect of any Center for Diseases Control (CDC) recommended vaccine for children, adults or travelers and BCG on risk of MS or disease relapse were included. Two reviewers independently extracted information from articles selected using a predefined datasheet. No significant change in the risk of developing MS after vaccination was found for BCG (OR 0.96, 95% CI 0.69–1.34), Hepatitis B (OR 1.00, 95% CI 0.74–1.37), Influenza (OR 0.97, 95% CI 0.77–1.23), Measles–Mumps–Rubella (MMR) (OR 1.02, 95% CI 0.64–1.61), Polio (OR 0.87, 95% CI 0.61–1.25) and Typhoid fever (OR 1.05, 95% CI 0.72–1.53). We found decreased risk of developing MS for Diphtheria (OR 0.60, 95% CI 0.40–0.90) and Tetanus (OR 0.68, 95% CI 0.54–0.84). Influenza immunization was also associated with no change in risk of MS relapse (RR 1.24, 95% CI 0.89–1.72). Risk of developing multiple sclerosis remained unchanged after BCG, Hepatitis B, Influenza, MMR, Polio and Typhoid fever immunization, whereas diphtheria and tetanus vaccination may be associated with a decreased risk of MS. Further research is needed for the remaining vaccines.     

A prospective study of the incidence, prevalence and mortality of multiple sclerosis in Leeds

Objective: To establish the prospective incidence of multiple sclerosis and mortality rates of people with multiple sclerosis in Leeds Health Authority and an updated prevalence of multiple sclerosis on 31 October 1999. Methods A population based prevalence register established on 30 April 1996 was maintained by prospectively registering all new cases of multiple sclerosis, flagging all cases with the National Health Service Central Register for notification of deaths and by registering all new clinical events. General practitioners notified patients with multiple sclerosis moving into or out of the area. Results 136 incident cases were prospectively registered from 30 April 1996 living in Leeds Health Authority (with an estimated resident population of 728 840). 57 deaths were notified. 792 people with multiple sclerosis were identified living in Leeds on 31 October 1999. The mean annual incidence rate for the three-year period 1996–1998 was 6.1/10⁵ (95 % CI: 5.1–7.2). The sex ratio of incident cases was 2.3 to 1 women to men. On 31 October 1999 the prevalence of multiple sclerosis in the Leeds Health Authority was 108.7/10⁵ (95 % CI: 101.2–116.5). This compares with a prevalence of 97.3/10⁵ (95 % CI: 90.3 –104.7) on 30 April 1996. The prevalence of definite and probable multiple sclerosis was 93.3/10⁵ (95 % CI: 86.4–100.6) and of suspected multiple sclerosis was 15.4/10⁵ (95 % CI 12.7 –18.5). Crude annual mortality rates of people with multiple sclerosis for 1997 and 1998 were 1.9/10⁵ (95 % CI: 1.1 to 3.2) and 3.2/10⁵ (95 % CI: 2.0 to 4.7). Multiple sclerosis was noted as the underlying cause of death in 8 (14 %) cases. Conclusion The incidence of multiple sclerosis in the Leeds Health Authority is similar to that in the south of the United Kingdom. The difference in successive prevalence figures is less than that published in other serial studies. Multiple sclerosis was notified as the underlying cause of death in a minority of deaths in people with multiple sclerosis. Received: 5 December 2000, Received in revised form: 23 March 2001, Accepted: 10 July 2001     

Prospective assessment of falls in Parkinson's disease

We studied prospectively the epidemiology, clinical impact and prediction of falls in 59 moderately affected patients with Parkinson's disease (PD) (mean UPDRS motor score 31.5; mean age 61 years) and 55 controls (mean age 60 years). At baseline, balance and gait were evaluated extensively. The retropulsion test (response to sudden shoulder pull) was executed first unexpectedly and five more times following prior warning. All persons used standardised scoring forms to document their falls during six months. Thirty patients (50.8 %) and eight controls (14.5 %) fell at least once (relative risk [RR] 6.1; 95 % confidence interval [CI] 2.5–15.1, p < 0.001). Recurrent (≥ 2) falls occurred in 15 patients (25.4 %), but in only two controls (RR 9.0; 95 % CI 2.0–41.7; p=0.001). Recurrent falls were more common among persons taking benzodiazepines (RR 5.0; 95 % CI 1.6–15.5; p < 0.01). Sixty-two percent of the falls in patients caused soft tissue injuries, but no fractures occurred. A fear of future falls was common (45.8 % of patients) and was accompanied by restriction of daily activities (44.1 % of patients). Seventy percent of falls reported by patients were ‘intrinsic’ (due to patient-related factors), but falls in controls were mainly (50 %) ‘extrinsic’ (due to environmental factors). None of the baseline posture and gait variables predicted falls adequately. The first ‘unexpected’ retropulsion test was more often abnormal than all subsequent (predictable) tests. Irrespective of its method of execution, the retropulsion test did not predict falls. A combination of asking for prior falls, disease severity and the Romberg test yielded the best overall diagnostic utility (sensitivity 65 % and specificity 98 %). Recurrent fallers were best predicted by disease severity (RR for Hoehn and Yahr stage 3 was > 100; 95 % CI 3.1–585) and asking for prior falls (RR 5.0; 95 % CI 1.2–20.9). We conclude that falls are common and disabling, even in relatively early stage PD. Recurrent fallers were best predicted by disease severity and presence of prior falls. Strategies to prevent falls in PD should particularly focus at intrinsic (patient-related) factors, such as minimising the use of benzodiazepines. Received: 18 December 2000, Received in revised form: 15 March 2001, Accepted: 25 March 2001     

Incidence of multiple sclerosis in the United Kingdom

Existing data on the incidence of multiple sclerosis (MS) in the UK have some limitations. Few studies have reported age- and sex-specific incidence rates of MS, and none of those is based on a large sample of the general population. Further, no published reports have provided age- and sex-specific incidence rates of MS by clinical course from onset. To estimate the age- and sex-specific incidence rate and lifetime risk of multiple sclerosis, we identified all new cases of MS during the period 1993–2000 in the General Practice Research Database, which includes health information on over three million Britons. Based on 642 incident cases, incidence rates of MS adjusted to the world population were 7.2 (95 % CI 6.5, 7.8) in women and 3.1 (95 % CI 2.6, 3.5) in men. The incidence of MS with relapsing-remitting onset was higher in women than in men (incidence rate ratio 2.5, 95% CI 2.1, 3.1), but there were no sex differences for primary-progressive MS (incidence rate ratio 1.1, 95% CI 0.7, 1.8). The estimated lifetime risk from birth of receiving an MS diagnosis was 5.3 per 1,000 in women and 2.3 per 1,000 in men. These results confirm the relatively high incidence of MS in the UK and show marked differences in the sex-specific pattern of MS incidence by clinical course from onset.     

Migration and multiple sclerosis in Alaskan military veterans

The objective is to provide the first estimates of the prevalence of multiple sclerosis (MS) in Alaskan white males including those migrant to and from the state. A case–control cohort design was utilized with a nationwide series of United States (US) veterans service-connected for MS and matched to pre-illness controls who had entered military service between 1960 and 1994. Among 3,758 white male MS cases and their 7,426 controls were 7 MS and 28 controls resident in Alaska at service entry, who provided an adjusted case/control (C/C) risk ratio for developing MS of 0.47 and an estimated prevalence rate of 22/100,000 population, but only 1 of the 7 had also been born in Alaska, for an estimated prevalence rate of 3.2 per 100,000 (95% confidence interval (CI): 0.08–17.80). The other 6 MS patients and their 26 controls, who migrated from another state to Alaska before onset, had an adjusted C/C ratio of 0.44 for a prevalence rate of 20.6 (95% CI: 7.56–44.90), significantly lower than the reported rate of 45.23 per 100,000 for all US white males in 1976. Another 9 MS patients and 7 controls born in Alaska, who had migrated to another state before entering service, provided an adjusted C/C risk ratio for developing MS of 2.44, with a highly significant elevated prevalence rate of 115 per 100,000 (95% CI: 52.6–218.1). In conclusion, these data suggest that Alaska is not a high-risk area for MS and indicate that migration before onset to Alaska from the high-risk coterminous US decreases the risk of MS and the opposite migration increases it. A formal prevalence survey of MS in Alaska is needed to support or refute these findings.     

Parkinson's disease, smoking and family history

There is growing evidence that both genetic and environmental factors play a role in the etiology of Parkinson's disease (PD). The hypothesis of an interaction between genetic and environmental risk factors has been little explored, and never using a population-based case-control study design. Our objective was to investigate the possible interaction between smoking and family history in the etiology of PD, as a part of a collaborative population-based case-control study. We included 149 nondemented PD patients ascertained in three European prevalence surveys using a two-phase design. Each patient was matched by age (±2 years), gender, and center to three controls drawn from the same populations (n=375). Presence of PD among first-degree relatives and smoking history were assessed through an interview for 127 cased and 306 controls. In the overall sample we found suggestive evidence that family history and eversmoking interact in determining the risk of PD (P=0.09), with individuals exposed to both risk factors having the highest risk (OR=10.0; 95% CI=2.0–49.6). Analyses were repeated after stratification into two age-groups (cutoff: 75 years). In older patients, the joint exposure to both risk factors was associated with a significant increase in the risk of PD (OR=17.6; 95% CI=1.9–160.5). Among younger subjects, the OR for joint exposure was not significant. In conclusion, our findings suggest that smoking and family history interact synergistically on a multiplicative scale in determining the risk of PD in individuals older than 75 years. Received: 28 January 2000 / Received in revised form: 1 May 2000 / Accepted: 28 May 2000     

Depression and the subsequent risk of Parkinson's disease in the NIH‐AARP Diet and Health Study

We conducted a case‐control study to examine the association between depression and Parkinson's disease (PD). Participants included 992 PD cases diagnosed after 2,000 and 279,958 individuals without PD from the NIH‐AARP Diet and Health Study follow‐up survey. Physician‐diagnosed depression and PD were self‐reported with information on the year of diagnosis in the following categories: before 1985, 1985–1994, 1995–1999, and 2000–present. Only PD cases diagnosed after 2000 were included in the analysis. Odds ratios (ORs) and 95% confidence intervals (CIs) were derived from logistic regression models, adjusted for age, gender, educational level, marital status, smoking, and coffee drinking. Individuals with depression diagnosed after 2000 were more likely to report a concurrent diagnosis of PD than those without depression (OR = 4.7, 95% CI = 3.9, 5.7). Depression diagnosed before 2000 was also associated with higher odds of PD diagnosed after 2000 (OR = 2.0, 95% CI = 1.6, 2.4). This association was stronger for depression diagnosed in 1995–1999 (OR = 2.7, 95% CI = 2.0, 3.6), but was also noted for depression diagnosed in 1985–1994 (OR = 1.6, 95% CI = 1.1, 2.3) or even before 1985 (OR = 1.7, 95% CI = 1.3, 2.3). This association was not modified by other factors and persisted in an analysis excluding participants who reported poor health status. The results suggest that depression may either be a very early symptom of PD or share common etiological factors with PD. © 2010 Movement Disorder Society     

Multiple sclerosis in the Republic of San Marino,Italian peninsula: an incidence and prevalence study from a high-risk area

Epidemiological studies on multiple sclerosis (MS) carried out in Southern Europe in the last years have shown a significant increase in the disease frequency. Previous surveys conducted in the Republic of San Marino, Northern Italian peninsula, identified that the population is at high risk for MS, with a prevalence of 51.6 per 100,000 population in 1982 and of 166.7 in 2005 and with a mean annual incidence of 7.9 per 100,000 for the period 1990–2005. The present work is a community-based intensive prevalence and incidence survey, by a complete enumeration approach, to update the prevalence and incidence of MS in the Republic of San Marino. The mean annual incidence for the period 2005–14 was 7.7 (95% CI 4.9–11.4) per 100,000, 3.3 (95% CI 1.1–7.6) for men and 11.9 (95% CI 7.2–18.6) for women. On 31 December 2014, 67 patients (19 men and 48 women), suffering from definite or probable MS and living in the Republic of San Marino, yielded a crude prevalence of 204.3 (95% CI 158.4–259.5) per 100,000, 117.8 (95% CI 70.9–183.7) for men and 288.2 (95% CI 212.4–383.3) for women. Our study has confirmed San Marino is an area at high risk for MS, in line with epidemiological data from continental Italy. The marked increase in MS prevalence over time in this population can be ascribable to increased survival and improved ascertainment, in the presence of a substantially stable, yet high, incidence rate.     

The organisation of health care and epidemiology of multiple sclerosis in France

STATE OF THE ART: According to the available previous studies, France is considered a zone of medium to high risk of multiple sclerosis (MS) with an estimated overall prevalence of at least 50/100,000 inhabitants, incidence rates were stable in some areas but increased over time in others and a strong ethnic effect on the incidence, clinical presentation, and course of MS is reported. RESULTS: Based on two health insurance survey the prevalence has been deduced. At January 1, 2003 from the data of agricultural health insurance the prevalence is evaluated at 65.5/100,000 inhabitants (95p.cent CI=62.5-67.5) with a gradient of North East towards South-West. The data from the national health insurance were very near. During the period 2000-2004, recent studies in Auvergne and Brittany demonstrated an annual incidence comprising between 4.2 and 5.1 per 100,000 inhabitants. In Lorraine, in a large population-based study, in December 31, 2004 the prevalence rate was 120/100,000 (95p.cent CI: 119 to 121). During the period 1990-2002, the average age- and sex-adjusted annual incidence rate was 5.5/100,000 (95p.cent CI: 4.4-6.6). In Lorraine, we found that the age-adjusted incidence rate increased during the period 1990-2002. The incidence of MS in women increased, whereas that in men did not change significantly during this period. Similarly, in Norway, North Ireland and Denmark, the incidence among women increased the most. The clinical features of MS were compared in 211 North Africans patients and 2 945 Europeans patients in two French MS centres (Lorraine and Nice) with definite MS according to McDonald's criteria. The course of MS appears more aggressive in North Africans than in Europeans patients. For example, we demonstrated a shorter time to reach the Expanded Disability Status Scale score of 4.0 (p=0.001) or 6.0 (p<0.0001) in North Africans patients. PERSPECTIVES AND CONCLUSIONS: The incidence rates found in these studies were comparable to those reported in several European populations. This undoubtedly places France in the category of regions with a high risk zone of MS. The incidence of MS in women increased; thus, exogenous (or epigenetic) factors vary over time and may affect men and women differently. The course of MS appears more aggressive in North Africans than in Europeans patients.     

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.     

The treated prevalence and incidence of bipolar disorder among national health insurance enrollees in Taiwan, 1996–2003

We used the NHI database to estimate the treated prevalence and incidence of bipolar disorder. The national health research institute (NHRI) provided a population based data file of 200,432 random subjects, about 1% of the population, for the study. We obtain a random sample of 136,045 subjects as a fixed cohort from 1996 to 2003. We identified study subjects who had at least one service claim during these years for either ambulatory or inpatient care with a principal diagnosis of bipolar disorder. The cumulative treated prevalence increased from 0.60 per 1,000 to 4.51 per 1,000 from 1996 to 2003. The annual treated incidence was around 0.48 per 1,000 per year to 0.71 per 1,000 per year during 1997–2003. Higher treated incidence was detected in the 45–64 (hazard ratio [HR], 1.63; 95% CI, 1.26–2.12) and 65 years or older age groups (HR, 1.57; 95% CI, 1.14–2.15), female (HR, 1.23; 95% CI, 1.04–1.46), non-aborigine (HR, 3.12; 95% CI, 1.26–7.75), with a fixed premium (HR, 1.60; 95% CI, 1.18–2.17), and those who lived in the eastern region (HR, 3.26; 95% CI, 2.31–4.59). According to the trends from 1996 to 2003, more persons with bipolar disorder had sought treatment in the NHI program in Taiwan. However, the treated prevalence of bipolar disorder in NHI was still lower than those of community studies in Western countries. In the future, we will continue to use NHI data to perform outcome evaluation and follow-up studies of bipolar disorder.     

Dual diagnosis in the suburbs: prevalence, need, and in-patient service use

  Background: Previous research has found comorbid severe mental illness and substance misuse (dual diagnosis) to be highly prevalent and to be associated with serious clinical and social problems, and increased service use in inner-city populations. The present study measures the prevalence of dual diagnosis, patterns of substance misuse, and associated in-patient use in a more demographically representative population in a suburban area of South London Method: We identified representative prevalent cases with psychotic illnesses who had been in contact with services in a geographically defined catchment area in Croydon over the previous 6 months. Cases of alcohol or substance misuse and dependence were identified through standardised interviews with patients and keyworkers, and socio- demographic and in-patient psychiatric service use data were also recorded. Results: Sixty-one of the 124 cases identified were randomly selected for interview, of whom 66% responded (N = 40). The prevalence rates of dual diagnosis (DD) observed were 33% (95% CI 18–47%) for any substance misuse, 20% (95% CI 8–32%) for alcohol misuse only, 5% (95% CI −16 to 26%) for drug misuse only, and 8% (95% CI −0.7 to 16%) for both drug and alcohol misuse. A lifetime history of any illicit drug use was observed in 35% of the sample (95% CI 20–50%). Patients who misuse alcohol and drugs were not found to be more likely to have been admitted to hospital in the previous 2 years, with little difference being observed between DD and psychosis-only patients in the mean number of in-patient admissions in this period (mean difference 0.25, 95% CI for difference −1.5 to 2.0). However, the DD patients were found to have spent on average over twice as long in hospital as other psychotic in-patients over the previous 2 years (mean difference 67.3 days, 95% CI for difference −205.9 to 71.2 days). DD patients were also found to have a greater number of unmet areas of need than the psychosis-only patients, which included accommodation, daytime activity, and social life, as well as substance misuse. Conclusions: The prevalence of substance misuse in patients with severe mental disorders in a suburban area is about as high as that for similar patients in inner-city London. While DD patients are not admitted more often than patients with psychosis alone, they have double the length of in-patient stay, which may be attributable to higher levels of unmet need. Accepted: 6 April 2000     

Prevalence and incidence of multiple sclerosis in the city of Monreale, Italy

The prevalence and incidence of multiple sclerosis (MS) in the city of Monreale, southern Italy were ascertained 10 years after a preliminary study in the same area. The study was undertaken in a population of 26,256 people. The patients were classified according to Poser’s criteria. The prevalence of MS on 31 December 1991 was 72.4 per 100,000 population. The incidence of MS for the period 1981–1991 was 3.3/100,000 per year. The mean period between onset and diagnosis of MS was 4.9 years for those patients found during this survey and 9.2 years for those in the first study. This study shows an increase of MS prevalence in Monreale city and a high incidence. The findings parallel the reduction of the lag time between onset and diagnosis. Received: 25 March 1997 Received in revised form: 30 June 1997 Accepted: 10 July 1997