Biomedical subjects

S C Newman

Publications and source records attributed to S C Newman.

At least 19 recordsLinked to original sources

PubMed1991

Suicide risk varies by subtype of affective disorder.

A cohort study of mortality was conducted in which 4022 patients with affective disorder who were treated during 1976-1985 in a mental institution or community clinic operated by the province of Alberta, Canada, were followed to the end of 1985. Vital status was determined by record linkage to the Statistics Canada Mortality Data Base. There were 326 deaths altogether, 96 from suicide. The standardized mortality ratio (SMR) for all causes of death combined was 2.3, and for suicide the SMR was 26.0. The SMR was also elevated for mental, circulatory and respiratory disorders, but not for neoplasms. The principal objective of the study was to determine whether there was a gradient of increasing mortality risk across the following diagnostic subgroups: manic disorder, bipolar affective disorder and major depressive disorder. A trend was found for suicide but not for all causes of death combined. The pattern of risk persisted after adjustment for the covariates sex, age and marital status in a Cox regression analysis.

Affective Disorders, Psychotic↗

PubMed1991

Mortality in a cohort of patients with schizophrenia: a record linkage study.

A retrospective study of mortality was conducted in which 3,623 patients with schizophrenia receiving treatment in Alberta between 1976 and 1985 were followed to the end of 1985. Vital status was determined by record linkage to the Statistics Canada Mortality Data Base. There were 301 deaths in the cohort, 97 of which were due to suicide. For all causes of death combined, the risk of mortality was approximately double that of the Alberta population; for suicide, risk was increased by a factor of 20. Mortality from circulatory, respiratory, digestive and genitourinary diseases was also greater than expected. It is estimated that those who suffer from schizophrenia have a life expectancy which is approximately 20% shorter than that of the general population. This study confirms earlier research demonstrating an increased risk of mortality associated with schizophrenia and extends those findings to specific causes of death.

Adolescent↗

PubMed1990

The efficiency of two-phase designs in prevalence surveys of mental disorders.

A two-phase survey of mental disorders uses a screening test to identify possible cases, thereby reducing the resources devoted to interviewing those not having the condition of interest. It is demonstrated using a mathematical model that in situations likely to be encountered in practice a two-phase design may lead to an increase in the efficiency of prevalence rate estimation, and also to an improvement in the efficiency of case detection. However, in certain applications the modest gain in efficiency may not warrant the additional complexity of a two-phase approach to data collection. Data from a survey of mental disorders in Edmonton, Canada, which collected information on 3258 community residents using the Diagnostic Interview Schedule and the General Health Questionnaire, are used to demonstrate how two-phase methods would have changed the efficiency of an actual survey.

Adult↗

PubMed1990

Health care utilization for emotional problems: results from a community survey.

A survey was conducted in which 865 randomly selected adult household residents of Edmonton, Alberta were interviewed to obtain information about health care in the preceding year. Eighty percent of the sample had seen a family physician, and eight percent of visits to family physicians involved a mental or emotional problem. Thirteen percent of the sample received professional help for a mental or emotional problem from some type of caregiver. The most frequently consulted professional was the family physician (eight percent of the sample), followed by psychologists and psychiatrists (each seeing two percent of the sample). Family physicians accounted for the greatest number of consultations for mental or emotional problems (41%), followed by psychologists (16%), social workers (12%) and psychiatrists (nine percent). Women were 27% more likely to seek a consultation than men, and consultation rates were highest in the group ranging in age from 35 to 44 years. There was also a strong relationship between having recent psychiatric symptoms and having had a consultation in the past year.

Adult↗

PubMed1990

Prevalence of psychiatric disorders and suicide attempts in a prison population.

A survey was conducted in which 180 randomly selected male prisoners ages 18 to 44 were interviewed using the Diagnostic Interview Schedule and other questionnaires. A comparison was made with 1,006 similarly aged male residents of Edmonton who were interviewed using the same instruments. Compared to the general population, prisoners were less likely to be married and were less well educated. There was a higher proportion of Native Indians in the prison sample and lower proportions of Oriental and other racial groups. Prisoners were twice as likely to have a lifetime psychiatric disorder compared with the general population, and all individual disorders investigated were more common in the prison population. Six month prevalence showed even greater rates compared with the general population, indicating recent symptoms. The number of individual disorders per prisoner was also higher than for the general population. Lifetime suicide attempts were seven times more frequent in prisoners than in the general population.

Adult↗

PubMed1989

Estimating the morbidity risk of illness from survey data.

A method is proposed for using survey data to estimate lower and upper bounds for the lifetime risk of an illness (morbidity risk). The mathematical model used, which is based on a three-state Markov process, assumes that the illness is irreversible, but allows differential mortality. The data required include information on age at onset collected from prevalent cases, and an estimate of the magnitude of differential mortality, which ordinarily must come from published research. The method is illustrated using data from a community survey of psychiatric illness conducted in Edmonton, Alberta, Canada.

Adolescent↗

PubMed1989

Design of two-phase prevalence surveys of rare disorders.

Two-phase medical surveys, in which a large sample is assessed with an inexpensive screening instrument and a subsample is selected for a more thorough diagnostic evaluation, appear to have great merit in the epidemiologic study of certain rare disorders. We present the optimal design of two-phase surveys when resources are fixed and when 100% of those screened positive in the first phase must be included in the second-phase evaluation. We go on to examine the relative efficiency of this two-phase design compared to a single-phase design in which all resources are used in a survey that employs the diagnostic evaluation. Given information on the accuracy of the screen and the prevalence of the disorder, the utility of the two-phase design depends on the relative cost of the screening to the diagnostic assessments.

Biometry↗

PubMed1988

A Markov process interpretation of Sullivan's index of morbidity and mortality.

Using intuitive arguments Sullivan described a method of combining morbidity data and certain ordinary life table to produce an estimate of illness-free life expectancy. In this paper we use an increment-decrement life table specified in terms of a Markov process to characterize illness-free life expectancy. We show that when the illness under consideration satisfies certain properties Sullivan's approach provides a convenient method of approximation. We illustrate theoretical results with hospital morbidity data on Canadian males for 1981.

Actuarial Analysis↗

PubMed1988

Odds ratio estimation in a steady-state population.

A three-state Markov process is used to model a steady-state population. The classical P = ID equation is derived, as well as a number of identities originally reported by Miettinen (Am J Epidemiol 1976; 103: 226-235) and Freeman and Hutchison (Am J Epidemiol 1980; 112: 707-723. Ibid. 1986; 124: 134-149). Using theoretical and empirical methods it is demonstrated that the odds ratio derived from a prevalence-prevalence case-control study conducted in a steady-state population will generally be a biased estimate of the incidence density ratio. However the bias will not likely be of practical importance unless the incidence density ratio is at least 10 or more.

Actuarial Analysis↗

PubMed1988

On the age-period-cohort analysis of suicide rates.

Cohort analysis has become a popular method of examining national trends in suicide rates. Most of the studies investigating this phenomenon have reported a cohort effect to be present. Using a graphical approach, this paper places cohort analysis within the broader framework of age-period-cohort analysis. It is shown that published reports may have failed to identify cohort effects due to using only portions of the available data. With a simple mathematical model it is demonstrated that what appears to be a cohort effect may be a period effect, and conversely. It is recommended that suicide rates be examined for both period and cohort effects before conclusions are drawn regarding trends, and that the complete data set be used for this purpose.

Adolescent↗

PubMed1988

Suicide trends in Canada, 1956-1981.

Using official suicide statistics, this study examined suicide rates in Canada over a 25-year span (1956 to 1981) as a function of age, gender, and geographical region. The analysis revealed that, for both sexes, the risk of suicide among the 15-24 year-olds increased at a faster rate than in any other age group. Male and female age-standardized suicide rates demonstrated an overall increase between 1956 and 1981. The trend for males was one of continuous increase, whereas female rates reached a maximum in 1976 and then decreased. Regional differences in suicide rates were also apparent. Although not strictly observed, a trend toward increasing risk of suicide in males as one proceeds westward across Canada was found. For females, a pattern of increasing suicide with more westerly location was also found, except that Ontario and the Prairie Provinces were in reverse order. Several possible explanations for these findings are presented.

Adolescent↗

PubMed1988

Design and field methods of the Edmonton survey of psychiatric disorders.

This paper describes aspects of the study design and field methods used in a survey of psychiatric disorders carried out in Edmonton, Alberta, Canada. Between January 1983 and May 1986, information was gathered on 3,258 community residents using the Diagnostic Interview Schedule and the General Health Questionnaire - 30 item version. The survey had a response rate of 71.6%. The nature of the sampling strategy used, features of the study instruments chosen, the selection and training of interviewers, and the approach to data analysis are briefly described.

Alberta↗

PubMed1988

Lifetime prevalence of psychiatric disorders in Edmonton.

3,258 randomly selected adult household residents of Edmonton were interviewed by trained lay interviewers using the Diagnostic Interview Schedule (DIS). Lifetime prevalence for 16 DIS/DSM III diagnoses are given. Overall 33.8% of the population had one or more diagnoses and, excluding substance use disorders, one fifth of the population had a diagnosis. The most common lifetime diagnosis was alcohol abuse/dependence, followed by phobia and major depressive episode. Men were more likely to have had substance use disorders and antisocial personality disorder and women more likely to have had major depressive episode, dysthymia, agoraphobia and simple phobia. Those who were married had generally lower lifetime prevalences. Those over age 65 had the lowest prevalence of any age groups.

Adolescent↗

PubMed1988

Period prevalence of psychiatric disorders in Edmonton.

3,258 randomly selected adult household residents of Edmonton were interviewed by trained lay interviewers using the Diagnostic Interview Schedule (DIS). Six-month prevalence figures for DIS/DSM III diagnoses are given, and selected figures for the one-month and one-year prevalence, and the one-year symptom-free rates. The six-month prevalence for any diagnosis is 17.1%, comparable to findings from other population studies using DSM III derived diagnoses, but lower than studies using the PSE. The prevalence rates for most disorders tended to be lowest in the elderly, but this was not as marked as the drop in lifetime prevalence. Men had higher prevalence for substance use disorders than women, but women had higher rates for affective disorders and anxiety/somatoform disorders. Prevalences for all disorders were either similar or lower in those who were married or living as though married, than in those who were not cohabiting. One-year symptom-free rates were highest for those with substance use disorders and lowest for those with anxiety/somatoform disorders - largely due to the persistence of phobias.

Adolescent↗

PubMed1988

Age of onset of psychiatric disorders.

Age of onset of psychiatric disorders was determined from a random sample of 3,258 household residents who were administered the DIS by trained lay interviewers. Onset was determined by the subject's recall of the age of the first symptom in those who met lifetime criteria for a diagnosis (DSM III without exclusions). The peak age of risk for most disorders was from the teens to 30 years, however a number of schizophrenics showed first symptoms before age 10. Few cases of any disorder had an onset in old age. The ages of onset are generally lower than those usually given from series of treated or hospitalized cases.

Adolescent↗

PubMed1988

Morbidity risk of psychiatric disorders.

Lifetime morbidity risks and percentiles of the age of onset distribution are given for a series of psychiatric disorders based on data collected as part of a community survey in Edmonton, Canada. The Diagnostic Interview Schedule (DIS) was used to gather information from 3,258 community residents between January 1983 and May 1986. Using a recently developed method of estimating morbidity risks from survey data, the lifetime morbidity risks for depression (male 16.4%, female 22.3%), schizophrenia (male 1.2%, female, 1.0%), and other disorders were calculated. These results are consistent with previously published reports.

Adolescent↗

PubMed1988

Prevalence of psychiatric disorders in the elderly in Edmonton.

Prevalence rates (six month and lifetime) for a random sample (N = 358) of the elderly living at home, are compared to the rates for a sample (N = 3,258) of the whole adult population of Edmonton and found to be generally lower in the elderly, except for cognitive impairment. These household resident results are similar to those reported from the United States using similar methods. A sample (N = 199) of the elderly living in institutions was found to have a very high overall prevalence of illness, mostly consisting of cognitive impairment (69%). It is estimated that over half of all cases of cognitive impairment live in institutions. This has considerable implications for the programs in institutions for the elderly, and also the need for institutions in the future, unless alternate means of care can be developed.

Aged↗

PubMed1988

Suicide attempts and psychiatric disorders in Edmonton.

The relationship between lifetime histories of attempting suicide, psychiatric disorders and other social problems was assessed by examining data from a random sample of 3,258 household residents of Edmonton who were administered the Diagnostic Interview Schedule (DIS) and the Goldberg General Health Questionnaire (GHQ) by trained lay interviewers. While the overall lifetime rate for suicide attempt was 3.6%, of particular interest was the finding that a lifetime history of a psychiatric disorder was 2.6 times more frequent in those who had made a suicide attempt than in those who had not. Alcoholism, major depressive episode and antisocial personality disorder carried the highest lifetime prevalence rates for male attempters, whereas major depressive episode, alcoholism and phobic disorder were the most common disorders in female attempters. Having thoughts and feelings about wanting to die and committing suicide were strongly associated with having made a suicide attempt in both males and females. GHQ results indicated that in comparison to nonattempters those who attempted suicide were most likely to have high current symptom levels.

Adolescent↗