Incidence and cumulative risk of treated schizophrenia in the prenatal determinants of schizophrenia study

The present study uses data from the Prenatal Determinants of Schizophrenia (PDS) Study to derive age- and sex-specific estimates of incidence and cumulative risk for DSM-IV schizophrenia. Although not designed as an incidence study, the PDS Study uses both a well-defined population under continuous followup and DSM-IV diagnoses. The originating cohort was established in Alameda County, California, during 1959-1967 and yielded 12,094 cohort members followed from 1981 to 1997 during the principal ages at risk for schizophrenia. Survival analytic techniques showed that schizophrenia incidence rates per 10,000 person-years for men were 9.4 for ages 15-19; 5.6 for ages 20-24; 3.3 for ages 25-29; and 0.9 for ages 30-34. Schizophrenia incidence rates per 10,000 person-years for women were 1.6 for ages 15-19; 1.3 for ages 20-24; and 4.1 for ages 25-29. The cumulative risk for schizophrenia by age 38 was 0.93 percent for men and 0.35 percent for women. These estimates of incidence rates and risk were higher than those in traditional incidence studies but similar to recent findings in other cohorts. Possible explanations for the apparently high rates of disorder include chance, design effects, and true variation in risk over time and place.     

50-year trends in the incidence of anorexia nervosa in Rochester, Minn.: a population-based study

OBJECTIVE: The aim of the study was to determine incidence and prevalence rates and long-term trends in incidence of anorexia nervosa by identifying all persons residing in the community of Rochester, Minn., during the 50-year period 1935 through 1984 who had the disorder. METHOD: From a community-based epidemiologic resource, 13,559 medical records with diagnoses of amenorrhea, starvation, weight loss, anorexia nervosa, or other conditions were screened to identify true cases of anorexia nervosa determined by using standard diagnostic criteria. RESULTS: One hundred eighty-one residents (166 female and 15 male) fulfilled the diagnostic criteria for anorexia nervosa; these were the incidence cases. Due to a quadratic trend in the rates for girls 10-19 years old, the incidence rate among female residents fell from 16.6 per 100,000 person-years in the 1935-1939 period to a low of 7.0 in 1950-1954 and increased to 26.3 in 1980-1984. The incidence rates for women 20 years old and older and for males remained constant. For females 15-24 years old, there was a linear increase. The overall age-adjusted incidence rate per 100,000 person-years was 14.6 for females and 1.8 for males. The prevalence rate per 100,000 population was 269.9 for females and 22.5 for males. CONCLUSIONS: Anorexia nervosa is more common than previously recognized. Among girls 15-19 years old it is a very common chronic illness. Its incidence has increased among females 15-24 years old but not among older women or among males.     

The epidemiology of anorexia nervosa in Denmark from 1973 to 1987: a nationwide register study of psychiatric admission

A nationwide register study of psychiatric admission for anorexia nervosa in Denmark yielded average incidence rates of 1.9 per 100,000 per year for females and 0.17 per 100,000 per year for males. The prevalence was 6.7 per 100,000 per year for females and 0.6 per 100,000 per year for males. The female-male ratio for first admissions was 11.8:1. The incidence of anorexia nervosa showed no trend in the general population, but an increase was found among psychiatric inpatients. This increase was explained by a reduction by one third in all psychiatric first admissions and in available psychiatric beds and augmented by an increase in readmissions of anorectic patients. Males were younger than females at first admission. Females were older at first admission from 1973 to 1977 than in later periods. Of males readmitted for non-eating disorders, more were psychotics and fewer psychopaths than among females. Age-period and age-cohort analysis of the 10- to 24-year-old females showed that only age exerted a significant independent influence on first-admission rates, whereas all 3 factors exerted significant independent influence on readmission rates. This might reflect changes in admission policy, greater diagnostic vigilance and changes in attitude towards weight, shape and fitness.     

The use of a psychiatric register in predicting the outcome "revolving door patient". A nation-wide cohort of first time admitted psychiatric patients

A nation-wide cohort of all first admitted patients to all Danish psychiatric institutions over a 1 year period and aged 15 years or more was followed for 10 years in the Danish psychiatric register. Revolving door patients were defined as patients with a minimum of four admissions and 1) no admission or discharge period lasting for more than 1/4 of the observation period or 2) at least four admissions over the first 1/4 of the observation period. The revolving door population comprised 1,397 patients with an incidence rate of 0.42 males and 0.32 females per 1,000. Forty-three point five percent belonged to the same diagnostic group at first and last diagnostic assessment ranging from 28.3% in "organic psychosis" to 57.6% in "neurosis". A multiple contingency analysis showed a number of variables at first admission significantly associated with the outcome "revolving door". Many were conditioned by others and the independent variables were "age group", "main diagnosis" and "sex". Patients aged 15-24 years constituted a high risk group among schizophrenics. The 15-24 age group was further at high risk among females with personality disorder or abuse and males with manic depressive and psychogenic psychosis. Living close to a psychiatric institution was in males associated with the outcome independently of age and diagnosis, in females it was restricted to personality disorder. Revolving door patients were significantly younger than others and more likely to suffer from schizophrenia or alcohol/substance abuse.     

Incidence and prevalence of amyotrophic lateral sclerosis in Harris County, Texas, 1985-1988

The incidence of amyotrophic lateral sclerosis was determined in Harris County, Texas, for the period 1985 through 1988. Amyotrophic lateral sclerosis cases were ascertained from four sources: area neurologists, hospitals, death certificates, and the Muscular Dystrophy Association. The age-adjusted incidences of 1.27 per 100,000 person-years in males and 1.03 per 100,000 person-years in females were lower than recent rates in the northern US, Canadian, and northern European studies but higher than rates in southern European studies. Comparisons with other recent incidence studies show less uniformity in occurrence of amyotrophic lateral sclerosis, in both the overall rates and in the age- and sex-specific patterns, than was suggested by mortality studies. The incidence of amyotrophic lateral sclerosis among blacks and whites was similar. Hispanic males had incidences similar to white males, although a deficit of female Hispanic cases was found in Harris County. The prevalence of amyotrophic lateral sclerosis peaked in the 65- to 74-year age group at 33 per 100,000 population among males and 19 per 100,000 population for females.     

Trends in head injury incidence in New Zealand: a hospital-based study from 1997/1998 to 2003/2004

Traumatic brain injury (TBI) is a leading cause of disability and death in young adults. Globally, the incidence of TBI hospitalizations is estimated at 200-300 people per 100,000 annually. Using a national health database, we examined the incidence of TBI-related hospital discharges (including 1-day stays) to New Zealand Hospitals from 1997/1998 to 2003/2004. Crude annual hospital-based incidence rates for the total population ranged from 226.9 per 100,000 in 1998/1999 to a high rate of 349.2 in 2002/2003. There was a noticeable increase in rates with the change from ICD-9 to ICD-10 diagnostic codes and there was also disparity in incidence rates according to ethnicity, age and gender. Crude annual hospital-based incidence rates for males and females in Maori (689/100,000 and 302.8/100,000 person-years) and Pacific Island populations (582.6/100,000 and 217.6/100,000 person-years) were much higher than those for the remaining population (435.4/100,000 and 200.9/100,000 person-years), particularly for males. The overall age-standardized hospital- based incidence rate for 2003/2004 was 342 per 100,000 per year (95% CI = 337-349/100,000), and 458 per 100,000 per year for Maori (95% CI = 438-479/100,000) with Maori males experiencing a peak in incidence between 30 and 34 years of age that was not evidenced for the wider population. Standardized hospital-based incidence rates for the total population and for Maori by age, gender and ICD-10 diagnostic codes are also examined.     

Incidence of cycloid psychosis

Summary The concept of cycloid psychosis has gained increasing acceptance during recent decades. Using the diagnostic criteria of Perris and Brockington, an intelligible delineation of a group of patients has been obtained. Few epidemiological data on cycloid psychosis have been reported so far. The objective of the present study was to describe the one-year incidence of cycloid psychosis in a clinical sample. The diagnostic registers of all patients hospitalized for a functional or an organic psychosis and discharged in the year 1983, in Lund, Sweden were investigated. 514 patients were identified of whom 83 were admitted to hospital for the first time. 29 of these patients had a functional psychosis and were below the age of 50. In this age group 7 cases (4 women, 3 men) fulfilled the diagnostic criteria of cycloid psychosis and thus constituted almost one fourth of all first admissions of functional psychoses that year. The one-year incidence for first admission in cycloid psychosis was 5.0 per 100000 inhabitants in women and 3.6 per 100000 inhabitants in men within the age group 15–50 years in the catchment area of 163 175 persons. We conclude that cycloid psychosis consitutes a considerable proportion of functional psychoses in both sexes.     

Youth suicide trends in Australian metropolitan and non-metropolitan areas, 1988-1997

OBJECTIVE: The objective of this study was to examine trends in suicide among 15-34-year-olds living in Australian metropolitan and non-metropolitan areas between 1988 and 1997. METHOD: Suicide and population data were obtained from the Australian Bureau of Statistics. We calculated overall and method-specific suicide rates for 15-24 and 25-34-year-old males and females separately, according to area of residence defined as non-metropolitan (< or = 20,000 people) or metropolitan. RESULTS: Between 1988 and 1997 suicide rates in 15-24-year-old non-metropolitan males were consistently 50% higher than metropolitan 15-24-year-olds. In 1995-1997, for example, the rates were: 38.2 versus 25.1 per 100,000 respectively (p < 0.0001). The reverse pattern was seen in 25-34-year-old females with higher rates in metropolitan areas (7.5 per 100,000) compared with non-metropolitan areas (6.1 per 100,000, p = 0.21) in 1995-1997. There were no significant differences according to area of residence in 25-34-year-old males or 15-24-year-old females. Over the years studied we found no clear evidence that suicide rates increased to a greater extent in rural than urban areas. Rates of hanging suicide have approximately doubled in both sexes and age groups in both settings over this time. Despite an approximate halving in firearm suicide, rates remain 3-fold higher among nonmetropolitan residents. CONCLUSION: Non-metropolitan males aged 15-24 years have disproportionately higher rates of suicide than their metropolitan counterparts. Reasons for this require further investigation. Hanging is now the most favoured method of non-metropolitan suicide replacing firearms from 10 years ago. Although legislation may reduce method-specific suicide the potential for method-substitution means that overall rates may not fall. More comprehensive interventions are therefore required.     

Incidence of migraine headache: a population-based study in Olmsted County, Minnesota.

To determine the incidence of clinically detected migraine headache in the defined population of Olmsted County, MN, 1979-1981, we screened over 6,400 patient records from several diagnostic rubrics using the unique resources of the Rochester Epidemiology Project for population-based studies. We identified 629 Olmsted County residents who fulfilled the International Headache Society's 1988 criteria for newly diagnosed migraine headache between 1979 and 1981. The overall age-adjusted incidence was 137 per 100,000 person-years for males and 294 per 100,000 person-years for females. The highest incidence in females was among those aged 20 to 24 years (689 per 100,000 person-years), and in males, the highest incidence was among those aged 10 to 14 years (246 per 100,000 person-years). From 1979 to 1981, there was a striking increase in the age-adjusted incidence in those under 45 years of age: the incidence increased 34% in women and 100% for men. This is the first population-based study of migraine incidence across all ages.     

The incidence of deep venous thrombosis and pulmonary embolism among patients with inflammatory bowel disease: a population-based cohort study

BACKGROUND: There is an impression mostly from specialty clinics that patients with inflammatory bowel disease (IBD) have an increased risk of venous thromboembolic disorders. Our aim was to determine the incidence of deep venous thrombosis (DVT) and pulmonary embolism (PE) from a population-based database of IBD patients and, to compare the incidence rates to that of an age, gender and geographically matched population control group. METHODS: IBD patients identified from the administrative claims data of the universal provincial insurance plan of Manitoba were matched 1:10 to randomly selected members of the general population without IBD by year, age, gender, and postal area of residence using Manitoba Health's population registry. The incidence of hospitalization for DVT and PE was calculated from hospital discharge abstracts using ICD-9-CM codes 451.1, 453.x for DVT and 415.1x for PE. Rates were calculated based on person-years of follow-up for 1984-1997. Comparisons to the population cohort yielded age-adjusted incidence rate ratios (IRR). Rates were calculated based on person-years of follow-up (Crohn's disease = 21,340, ulcerative colitis = 19,665) for 1984-1997. RESULTS: In Crohn's disease the incidence rate of DVT was 31.4/10,000 person-years and of PE was 10.3/10,000 person-years. In ulcerative colitis the incidence rates were 30.0/10,000 person-years for DVT and 19.8/10,000 person-years for PE. The IRR was 4.7 (95% CI, 3.5-6.3) for DVT and 2.9 (1.8-4.7) for PE in Crohn's disease and 2.8 (2.1-3.7) for DVT and 3.6 (2.5-5.2) for PE, in ulcerative colitis. There were no gender differences for IRR. The highest rates of DVT and PE were seen among patients over 60 years old; however the highest IRR for these events were among patients less than 40 years. CONCLUSION: IBD patients have a threefold increased risk of developing DVT or PE.     

A comparison of Australian suicide rates in 1969-73 and 1976-80

Australian suicide rates were compared for the 1969-73 and 1976-80 periods by age, sex and State. Rates for males were generally at least twice those for females. The sex difference was marked, irrespective of age, State and time period. Middle-aged and older Australians generally had higher rates than 20-29-year-olds, although this finding was not consistent by State for males. The national age-standardised suicide rate for all age groups combined decreased between the 1969-73 period and 1976-80 both for males and (more so) for females. However, there was a 24% increase for 20-29-year-old males. While the suicide rate for 20-29-year-old females decreased between the 1969-73 period and 1976-80, an analysis of yearly trends within the 1976-80 period revealed an upward trend for individuals aged 20-29 years, for both females and males.     

Early Psychosis Prevention and Intervention Centre long-term follow-up study of first-episode psychosis: methodology and baseline characteristics

Aim: This paper reports the rationale, methodology and baseline characteristics of a large long‐term follow‐up study of first‐episode psychosis from a geographically defined catchment area. Method: A total of 723 first‐episode psychosis patients were recruited from a specialized early psychosis service between 1989 and 2001 and prospectively followed up at a median of 7.4 years after initial presentation. Participants’ baseline demographic, clinical and functional characteristics are described. Sampling bias at study recruitment was assessed by comparison with a more complete sample of Early Psychosis Prevention and Intervention Centre (EPPIC) cases rated directly from the medical records. Results: At baseline, 57% of the sample were diagnosed with schizophrenia or schizophreniform disorder, whereas the full range of psychotic disorders was represented. Statistical analysis confirmed that the sample recruited was representative of total EPPIC‐treated incident cases. Conclusions: The EPPIC long‐term follow‐up study is a large and epidemiologically representative first‐episode psychosis cohort that has been subsequently prospectively followed up over a long period. Such a sample provides a rare opportunity to study the course and outcome of psychotic disorders.     

Epidemiology of myasthenia gravis in the province of Trento (northern Italy).

The epidemiology of myasthenia gravis (MG) was studied in the province of Trento (northern Italy) among 444,879 inhabitants. On prevalence day (December 31, 1990) the crude rate was 82.9 per million population: 113 for females and 50.7 for males. The incidence rate was 7.4 per million per year: 10.8 for females and 4.6 for males. Over the same observation period (1981-1990), we calculated a death rate of 1.12 per million population per year. MG predominates in females. Nevertheless, we observed some differences related to age and to presence of thymoma, and our data supports the recognition of three types of MG: (1) predominating in females with a peak frequency at about 20-29 years; (2) affecting both males and females, with a frequency increasing with age, and (3) associated with thymoma.     

The incidence of anorexia nervosa on Curaçao

OBJECTIVE: Although anorexia nervosa was once thought to occur only in affluent societies, cases have now been documented across the globe. To examine whether anorexia nervosa emerges in societies undergoing socioeconomic transition, the authors studied the incidence of anorexia nervosa on the Caribbean island of Cura?ao. METHOD: The authors contacted the full range of community health and service providers on Cura?ao, including dietitians, school counselors, and all 82 general practitioners. They also studied inpatient records for 84,420 admissions to Cura?ao General Hospital and two private hospitals in 1995-1998. Probable-incident subjects were interviewed. RESULTS: The incidence rates in 1995-1998 per 100,000 person-years for anorexia nervosa on Cura?ao were 1.82 (95% confidence interval [CI]=0.74-2.89) for the total population and 17.48 (95% CI=4.13-30.43) for the high-risk group of 15-24-year-old females. No cases were found among the majority black population. For the Cura?ao mixed and white population, the incidence rate per 100,000 person-years for anorexia nervosa was 9.08 (95% CI=3.71-14.45). CONCLUSIONS: The overall incidence of anorexia nervosa on Cura?ao is much lower than in the affluent societies of the United States and Western Europe. Within Cura?ao, sociocultural factors appear to be associated with differential incidence rates of anorexia nervosa. The incidence of anorexia nervosa among the majority black population is nil, while the incidence among the minority mixed and white population on Cura?ao is similar to that of the United States and the Netherlands.     

Medulloblastoma: a population-based study of 532 cases

Five hundred thirty-two cases of medulloblastoma (males n = 327 and females n = 205), aged 0 to 86 years diagnosed between 1973 and 1986 were studied to determine the incidence in different geographic regions of the United States and to evaluate the effect of various factors on survival. The median age was 9 years and average follow-up time was 45 months. The overall incidence rate was 1.8 per one million person-years. Variables that were statistically significant (p less than 0.05) in a multivariate model determining survival in rank order were treatment group, sex, geographic region, year group and age. This observational study found that 1) age and sex were statistically significant factors in describing the incidence rates, whereas year group and geographic region were not; 2) no incidence peak in the third decade of life was observed; 3) a significant improvement in survival was observed in the combined 1978 to 1986 year groups relative to the 1973 to 1977 year group; 4) the overall 5-year survival probability was 45%; and 5) there has been an increase over time in the use of more than two modalities of treatment.     

Decreasing rates of first-admission diagnoses of schizophrenia among females in Denmark 1970-84

In Denmark age-standardized rates of first-admission diagnoses of schizophrenia in females decreased significantly by 44% from 1970 to 1984. The slope of the regression line is -0.21 per 100,000 female inhabitants aged 15 years or more per year. All age groups, but especially the age group 45-54 years, contributed to the decrease in rates. Coinciding with the decrease in schizophrenia rates, an increase in age-standardized rates of borderline states in the age group 15-44 years occurred. The slope of the regression line is +0.53 per 100,000 per year. The results are compared with those in males and possible causes of the decrease are discussed. There is every probability that, as in males, part of the decrease is due to changes in diagnostic habits.     

Age-at-first-registration for affective psychosis and schizophrenia

We compared the age-at-first-registration for patients with schizophrenia and affective psychosis in a statewide mental health register. After excluding those receiving (1) a diagnosis of both schizophrenia (ICD-9 295.x) and affective psychosis (ICD-9 296.x), or (2) a diagnosis of ICD-9 296.1 (which can cover "major depressive episode"), we adjusted the distributions for the age structure of the background general population. We found that all distributions showed a wide age range of onset, with a similar male modal age group of 20-24 for schizophrenia and 25-29 for affective psychosis. The female modal age group was 50-54 for both diagnoses. Although more individuals were diagnosed with schizophrenia (males = 2,434, females = 1,609) than with affective psychosis (males = 670, females = 913), the shape of the two distributions was similar. This finding suggests that factors influencing age-at-first-registration for schizophrenia and affective psychosis may be similar, especially for females.     

Incidence and diagnostic stability of ICD-10 acute and transient psychotic disorders

OBJECTIVE: The 10th Revision of the International Classification of Diseases (ICD-10) introduced a new diagnostic category, F23 acute and transient psychotic disorders (ATPD) to embrace clinical concepts such as the French bouffée délirante, Kleist and Leonhard's cycloid psychoses, and the Scandinavian reactive and schizophreniform psychoses. The relative rarity of these disorders and insufficient follow-up studies with adequate numbers of patients makes ATPD classification as uncertain as their validity. The aim of this study was to evaluate incidence and validity of ATPD in terms of diagnostic stability. METHOD: A 6-year analysis of readmission patterns of all subjects listed in the Danish psychiatric central register as having been first-ever admitted to hospital or treated in outpatient services with a diagnosis of ATPD from January 1 to December 31, 1996, was conducted. RESULTS: The incidence of ATPD was 9.6 per 100 000 population, with a higher rate of females than males (9.8 vs 9.4). Incidence rates by age group were higher for males than for females, with a marked reversal of this pattern above 50 years. This contrasted with incidence of schizophrenia that was almost twice as high in males as in females, particularly in the 20-29 year age group. Of 416 cases with a first-admission diagnosis of ATPD, an increasing number tended to change on subsequent admissions, nearly half to another F2 category schizophrenia and related disorders. The overall stability rate reached only 39%. CONCLUSIONS: Although demographic differences from schizophrenia are topics that deserve further research, poor diagnostic stability argues against attempts to separate ATPD from borderland disorders.     

Incidence and mortality of Parkinson's disease in older Canadians

ObjectiveTo estimate the age-specific incidence of Parkinson’s disease (PD) in elderly persons in the Canadian province of British Columbia (BC). All-cause and injury mortalities and relative risk of death for those persons with PD were also examined.MethodsA historical cohort study was conducted using 5 provincial administrative databases from 1991/92 to 2000/2001. A series of algorithms based on the databases were created for case ascertainment of PD for persons 65 years or older. Crude and age-specific incidence and mortality rates were calculated using person-years of follow-up as the denominator. The impact of PD on all-cause and injury mortalities was examined using multivariate Cox regression models to provide adjusted hazard ratios.Results10,910 incidence cases over 6,051,682 person-years of follow-up were identified. The crude annual incidence rate was 252 per 100,000 person-years. Over the nine year period, age standardized incidence for males ranged from 207 to 396 per 100,000 person-years and 127 to 259 per 100,000 person-years for females. Persons with PD were at a 43% greater risk of all-cause mortality and specifically, 51% greater risk of injury mortality.ConclusionsIncidence of PD is substantially higher in advanced age with age adjusted increases for both all-cause and injury mortalities. These findings also highlight falls as a primary factor for injury mortality in PD.     

Mental retardation in over half-a-million consecutive livebirths: an epidemiological study

Prevalence and incidence of all levels of mental retardation were investigated in the population of British Columbia. Ascertainment was through the British Columbia Health Surveillance Registry. The minimum prevalence for all levels of retardation among the 15- to 29-year age group, where ascertainment was best, was 7.7 per 1,000 (8.8 per 1,000 males, 6.6 per 1,000 females). Minimum ascertainment (incidence) of retardation in the 1952 to 1966 birth cohort was 9.3 per 1,000 livebirths (9.9 per 1,000 males, 8.6 per 1,000 females). Data were also presented on lagtime (time from birth until a retarded person is identified in association with the level of functioning and the presence or absence of disabilities in addition to mental retardation.