Biomedical subjects

R C Kessler

Publications and source records attributed to R C Kessler.

At least 109 records · Page 6Linked to original sources

PubMed1997

Differences in the use of psychiatric outpatient services between the United States and Ontario.

BACKGROUND: The relation between health insurance and the use of mental health services is unclear. We compared the use of outpatient services for psychiatric problems in the United States and Ontario, Canada, among young and middle-aged adults according to self-reports of disorders listed in the Diagnostic and Statistical Manual of Mental Disorders (third edition, revised) and to other indicators of need. METHODS: We analyzed two general-population surveys carried out separately in the United States and Ontario in 1990 that used identical assessments of need for services and questions about their use by persons 15 to 54 years of age. RESULTS: Respondents in the United States were significantly more likely than those in Ontario to report having had psychiatric disorders, poor mental health, or workdays lost or cut short because of psychiatric problems in the previous year. A significantly higher proportion of respondents in the United States (13.3 percent) than in Ontario (8.0 percent) had obtained outpatient treatment in the previous 12 months for psychiatric problems. However, an analysis of subgroups found that the higher probability of the use of services in the United States was confined to people with less severe mental illness. The average number of visits did not differ significantly between the two countries among patients who had similar numbers of psychiatric disorders over the same time periods. There was a stronger match in Ontario than in the United States between the use of services and the measures of perceived need we considered. CONCLUSIONS: Although the mental health care system in the United States provides treatment to a larger proportion of the population than that in Ontario, the match between some measures of need and treatment is not as strong in the United States. Any plans to expand coverage for psychiatric disorders in the United States must address this problem.

Adolescent↗

PubMed1997

Prevalence and demographic correlates of symptoms of last year dependence on alcohol, nicotine, marijuana and cocaine in the U.S. population.

The prevalence of last year use of alcohol, cigarettes, marijuana and cocaine in the U.S. population and conditional prevalence of a proxy measure of last year dependence among last year users of each drug class were assessed as a function of age, gender and ethnicity. Analyses were based on three aggregated waves (1991, 1992 and 1993) of the nationally representative samples of the general population aged > or = 12 interviewed in the National Household Surveys on Drug Abuse (n = 87915). An approximation of DSM-IV drug-specific last year dependence for each drug class was derived from self-reported symptoms of dependence, data on frequency and quantity of use and drug-related problems reported for the last year. Descriptive and multivariate analyses were conducted. The inclusion of cigarettes among the drugs, the large number of cases and the wide age range of respondents (> or = 12) enable us to make drug, age, gender and ethnic comparisons not otherwise possible in any other data set. The proxy measure of dependence, however, has limitations. The five major findings are that: (1) nicotine is the most addictive of the four drugs we examined; (2) among female last year users of alcohol and marijuana, adolescents are significantly more at risk for dependence than any other age group of women; (3) conditional prevalences of last year dependence on alcohol, marijuana and cocaine are higher among adolescent females than adolescent males but significantly different only for cocaine; (4) among adults, the rates of dependence are higher among males than among females for alcohol and marijuana, but lower for nicotine; and (5) among last year users, whites are more likely than any other ethnic group to be dependent on nicotine and blacks to be dependent on cocaine.

Adolescent↗

PubMed1997

Lifetime co-occurrence of DSM-III-R alcohol abuse and dependence with other psychiatric disorders in the National Comorbidity Survey.

OBJECTIVE: To study patterns of co-occurrence of lifetime DSM-III-R alcohol disorders in a household sample. METHODS: Data came from the National Comorbidity Survey (NCS), a nationally representative household survey. Diagnoses were based on a modified version of the Composite International Diagnostic Interview. RESULTS: Respondents with lifetime NCS/DSM-III-R alcohol abuse or dependence had a high probability of carrying at least 1 other lifetime NCS/DSM-III-R diagnosis. Retrospective reports have suggested that most lifetime co-occurring alcohol disorders begin at a later age than at least 1 other NCS/DSM-III-R disorder. Earlier disorders are generally stronger predictors of alcohol dependence than alcohol abuse and stronger among women than men. Lifetime co-occurrence is positively, but weakly, associated with the persistence of alcohol abuse among men and of alcohol dependence among both men and women. CONCLUSIONS: Caution is needed in interpreting the results due to the fact that diagnoses were made by nonclinicians and results are based on retrospective reports of the age at onset. Within the context of these limitations, though, these results show that alcohol abuse and dependence are often associated with other lifetime DSM-III-R disorders and suggest that, at least in recent cohorts, the alcohol use disorders are usually temporally secondary. Prospective data and data based on clinically confirmed diagnoses are needed to verify these findings.

Age of Onset↗

PubMed1997

Coming to terms with the terms of risk.

Terms such as risk, risk factors, and especially the term cause are inconsistently and imprecisely used, fostering scientific miscommunication and misleading research and policy. Clarifying such terms is the essential first step. We define risk and a risk factor (protective factor) and their potency, set out the conceptual basis of the methods by which risk factors are identified and potency demonstrated, and propose criteria for establishing the status of a risk factor as a fixed or variable marker or a causal risk factor. All definitions are based on the state of scientific knowledge (empirical documentation), rather than on hypotheses, speculations, or beliefs. We discuss common approaches and pitfalls and give a psychiatric research example. Imprecise reports can impede the search for understanding the cause and course of any disease and also may be a basis of inadequate clinical or policy decision-making. The issues in risk research are much too important to tolerate less than precise terminology or the less than rigorous research reporting that results from imprecise and inconsistent terminology.

Causality↗

PubMed1997

Prevalence, correlates, and course of minor depression and major depression in the National Comorbidity Survey.

Data from the National Comorbidity Survey are used to study the lifetime prevalences, correlates, course and impairments associated with minor depression (mD), major depression 5-6 symptoms (MD 5-6), and major depression with seven or more symptoms (MD 7-9) in an effort to determine whether mD is on a continuum with MD. There is a monotonic increase in average number of episodes, average length of longest episode, impairment, comorbidity, and parental history of psychiatric disorders as we go from mD to Md 5-6 to MD 7-9. In most of these cases, though, the differences between mD and MD 5-6 are no longer than the differences between MD 5-6 and MD 7-9, arguing for continuity between mD and MD. Coupled with the finding from earlier studies that subclinical depression is a significant risk factor for major depression, these results argue that minor depression is a variant of depressive disorder that should be considered seriously both as a target for preventive intervention and for treatment. The paper closes with suggestions regarding the analysis of mD subtypes in future longitudinal studies.

Adolescent↗

PubMed1997

Contributions of risk-factor research to developmental psychopathology.

Risk-factor research refers to the study of antecedent conditions and subsequent outcomes and the ways in which these are interrelated. The research encompasses a broad range of questions and research strategies. The paper discusses the characteristics and contributions of risk-factor research in the context of developmental psychopathology. The ways in which causal paths are conceptualized, the capacity to integrate multiple influences, and applications that can be derived from the findings are discussed. The progression of research is illustrated in relation to key concepts (correlate, risk factor, marker, causal risk factor) that reflect varied levels of understanding antecedent-outcome relations. The identification of causal relations, progressions, and paths over the course of development and the interplay of theory, research, and application are illustrated and discussed.

Adolescent↗

PubMed1997

The prediction of length of major depressive episodes: results from an epidemiological sample of female twins.

In order to examine factors that influence the time to recovery (TTR) from depressive episodes in women, we examined members of 1030 female-female twin pairs of known zygosity, ascertained from a population-based twin registry. We predicted, in a Cox model, TTR in 235 women with an onset of an episode of major depression (MD) in the last year meeting DSM-III-R criteria. The median and mean TTR for episodes of MD was 42 and 82 days, respectively; only 2.2% of women had not recovered by 1 year. Four variables predicted TTR: financial difficulties, obsessive-compulsive symptoms, severe life events (SLEs), and genetic risk. Dividing all depressive episodes meeting symptomatic DSM-III-R criteria into early (5-28 days) and late (> 28 days) phases, significant predictors of TTR early in the course of illness (income, parental protectiveness and separation, personality, lifetime traumas and SLEs) differed from those that predicted TTR later in the depressive episode (health, social support, obsessive-compulsive symptoms, SLEs and genetic risk). Including cases with chronic MD increased the strength of personality, financial problems and genetic risk as predictors of slow TTR. These exploratory analyses suggest that TTR from MD in women is influenced by multiple environmental, temperamental and genetic factors. Predictors of TTR early and later in the course of MD may differ qualitatively, suggesting different processes in recovery from brief versus prolonged depressions.

Chronic Disease↗

PubMed1997

The impact of psychiatric disorders on work loss days.

BACKGROUND: To examine relationships between recent DSM-III-R psychiatric disorders and work impairment in major occupational groups in the US labour force. METHOD: Data are from the US National Comorbidity Survey (NCS), a survey of respondents ages 15-54 in the US. Employed people are the focus of the report. RESULTS: There is substantial variation across occupations in the 30-day prevalences of NCS/ DSM-III-R psychiatric disorders, with an average prevalence of 18.2% (range: 11.0-29.6%) for any disorder. The average prevalences of psychiatric work loss days (6 days per month per 100 workers) and work cutback days (31 days per month per 100 workers), in comparison, do not differ significantly across occupations. Work impairment is more strongly concentrated among the 3.7% of the workforce with co-morbid psychiatric disorders (49 work loss days and 346 work cutback days per month per 100 workers) than the 14.5% with pure disorders (11 work loss days and 66 work cutback days per month per 100 workers) or the 81.8% with no disorder (2 work loss days and 11 work cutback days per month per 100 workers). The effects of psychiatric disorders on work loss are similar across all occupations, while effects on work cutback are greater among professional workers than those in other occupations. CONCLUSION: The results reported here suggest that work impairment is one of the adverse consequences of psychiatric disorders. The current policy debate concerning insurance coverage for mental disorders needs to take these consequences into consideration.

Absenteeism↗

PubMed1997

The epidemiology of DSM-III-R bipolar I disorder in a general population survey.

BACKGROUND: Data are presented on the general population epidemiology of DSM-III-R bipolar I disorder in the United States. METHODS: Data come from the US National Comorbidity Survey (NCS), a general population survey of DSM-III-R disorders. A modified version of the Composite International Diagnostic Interview was used to make diagnoses. RESULTS: A small (N = 59) clinical reappraisal study showed that the only manic symptom profile that could validly be assessed with the CIDI is characterized by euphoria, grandiosity and the ability to maintain energy without sleep, which described approximately half of all clinically validated bipolar I cases in the NCS. Further analysis focused on this symptom profile, which involved N = 29 cases in the total sample. Lifetime prevalence was estimated to be 0.4% and 12-month prevalence only slightly lower. Caseness was negatively related to income, education and age, positively related to urbanicity, and elevated among the previously married, never married and non-whites. All cases reported at least one other NCS/DSM-III-R disorder and 59.3% reported that their episode of bipolar disorder (either mania or depression) occurred at a later age than at least one other NCS/DSM-III-R disorder. Although 93.2% of lifetime cases reported some lifetime treatment, only 44.7% of recent cases were in treatment. CONCLUSIONS: The type of bipolar disorder examined here is highly chronic, co-morbid and impairing. Increased efforts are required to attract current cases into appropriate treatment. Methodological research is needed to develop more accurate measures of other bipolar symptom profiles for use in general population epidemiological studies.

Age of Onset↗

PubMed1997

Childhood adversity and adult psychiatric disorder in the US National Comorbidity Survey.

BACKGROUND: Survey data are presented on the associations between retrospectively reported childhood adversities and subsequent onset and persistence of DSM-III-R disorders. METHODS: Data come from the US National Comorbidity Survey, a large survey of the US household population. RESULTS: Twenty-six adversities were considered, including loss events (e.g. parental divorce), parental psychopathologies (e.g. maternal depression), interpersonal traumas (e.g. rape) and other adversities (e.g. natural disaster). These adversities were consistently associated with onset, but not persistence, of DSM-III-R mood disorders, anxiety disorders, addictive disorders and acting out disorders. Most bivariate associations with onset attenuated in models that controlled for clustering of adversities and for lifetime co-morbidities among psychiatric disorders. Multivariate effects of adversities in logistic models were additive, which means that they have multiplicative effects on probability of disorder onset. Adversities showed little specificity. An analysis of time decay showed that the effects of childhood adversities on disorder onset persist beyond childhood. CONCLUSIONS: The existence of strong clustering among childhood adversities and lifetime co-morbidity among adult disorders means that caution is needed in interpreting the results of previous single-adversity single-disorder studies as documenting unique effects of specific childhood adversities on specific adult disorders. Future studies need to assess a broader range of adversities and disorders and to explore the existence and effects of commonly occurring adversity clusters. Replication is needed to verify that the effects of childhood adversities are mostly on first onset rather than on the creation of vulnerabilities that lead to increased risk of persistence.

Adolescent↗

PubMed1997

Adult attachment in a nationally representative sample.

The explosion of adult attachment research in the last decade has been limited by its reliance on college student and distressed samples. Using a large nationally representative sample of American adults, the authors examined the relation of sociodemographics, childhood adversity, parental representations, adult psychopathology, and personality traits to adult attachment in an effort to replicate previous findings and extend the theory. Distribution of adult attachment styles was similar to that in prior studies: 59% secure, 25% avoidant, and 11% anxious. Adult attachment was associated with several sociodemographic variables (e.g., income, age, race) not previously studied. Childhood adversities of an interpersonal nature were strongly related to insecure adult attachment. Various types of adult psychopathologies and personality traits were also strongly related to adult attachment. Implications for adult attachment theory and future research are discussed.

Adolescent↗

PubMed1997

The effects of stressful life events on depression.

This chapter reviews recent research on the relationship between stressful life experiences and depression. A distinction is made between aggregate studies of overall stress effects and focused studies of particular events and difficulties. A distinction is also made between effects of life stress on first onset of depression and on the subsequent course of depression. Although the available evidence suggests that acute stressful life events can lead to the recurrence of episodes of major depression, a series of methodological problems compromise our ability to make clear causal inferences about the effects of life events on first onset of major depression or about the effects of chronic stress on either onset or recurrence of depression. The main problems of this sort are discussed, and recommendations made for ways of addressing these problems in future studies.

Adaptation, Psychological↗

PubMed1997

Social consequences of psychiatric disorders, II: Teenage parenthood.

OBJECTIVE: The subject of this study was the relation between retrospectively reported early-onset psychiatric disorders and subsequent teenage parenthood in the general population. METHOD: The data were from 5,877 respondents aged 15-54 years in the National Comorbidity Survey, a nationally representative household survey. Information on respondents' DSM-III-R anxiety disorders, mood disorders, substance abuse disorders, and conduct disorder, age at the birth of the first child, and teenage sexual activity was collected in face-to-face interviews. RESULTS: Early-onset psychiatric disorders were associated with subsequent teenage parenthood among both females and males, with significant odds ratios of 2.0-12.0 and population attributable risk proportions of 6.2%-33.7%. Disaggregation analyses showed that disorders were associated with increased probability of sexual activity but not with decreased probability of using contraception. CONCLUSIONS: These results add to a growing body of evidence that psychiatric disorders are associated with a variety of adverse life consequences. The current policy debate concerning universal insurance coverage needs to take this into consideration. Planners of interventions aimed at preventing teenage pregnancy should consider including a mental health treatment component in their intervention packages. Mental health professionals treating adolescents need to be sensitized to their higher risk of pregnancy, while family doctors and specialists treating teenage mothers or their children need to be sensitized to the mothers' higher risk of psychiatric disorder.

Adolescent↗

PubMed1997

The familial aggregation of common psychiatric and substance use disorders in the National Comorbidity Survey: a family history study.

BACKGROUND: Most family studies of psychiatric disorders examine one syndrome at a time, and identify probands in clinical rather than epidemiological settings. METHOD: In the National Comorbidity Survey, 5877 respondents were asked about the history of five psychiatric disorders in their parents: major depression (MD), generalised anxiety disorder (GAD), antisocial personality disorder (ASP), alcohol abuse/dependence (AAD) and drug abuse/dependence (DAD). RESULTS: Significant familial aggregation was seen for all disorders. Controlling for other disorders produced only modest reductions in the odds ratios for MD, GAD and AAD and larger reductions for ASP and DAD. The familial transmission of these disorders can be explained by underlying vulnerabilities to internalising and to externalising disorders transmitted across generations with moderate fidelity. CONCLUSIONS: Familial aggregation of common psychiatric and substance use disorders is substantial in epidemiologic samples. The examined environmental adversities account for little of the observed parent-offspring transmission of these conditions.

Adolescent↗

PubMed1997

The use of outpatient mental health services in the United States and Ontario: the impact of mental morbidity and perceived need for care.

OBJECTIVES: This study compared the associations of individual mental health disorders, self-rated mental health, disability, and perceived need for care with the use of outpatient mental health services in the United States and the Canadian province of Ontario. METHODS: A cross-sectional study design was employed. Data came from the 1990 US National Comorbidity Survey and the 1990 Mental Health Supplement to the Ontario Health Survey. RESULTS: The odds of receiving any medical or psychiatric specialty services were as follows: for persons with any affective disorder, 3.1 in the United States vs 11.0 in Ontario; for persons with fair or poor self-rated mental health, 2.7 in the United States vs 5.0 in Ontario; for persons with mental health-related disability. 3.0 in the United States vs 1.5 in Ontario. When perceived need was controlled for, most of the between country differences in use disappeared. CONCLUSIONS: The higher use of mental health services in the United States than in Ontario is mostly explained by the combination of a higher prevalence of mental morbidity and a higher prevalence of perceived need for care among persons with low mental morbidity in the United States.

Cross-Sectional Studies↗

PubMed1997

Mental health care use, morbidity, and socioeconomic status in the United States and Ontario.

This study focuses on mental health problems and compares the association of demographic and socioeconomic factors to the use of mental health specialty care and general medical care in the United States and the Canadian province, Ontario. It also examines how lack of insurance coverage in the United States and perceived need for care affects differences between the two countries. We employ a cross-sectional study design using the 1990 U.S. National Comorbidity Survey and the 1990 Mental Health Supplement to the Ontario Health Survey. Overall, 8.8% of Americans report one or more visits to the health sector for a mental health problem, compared to 6.9% of Canadians in Ontario. Americans with the highest incomes and no mental morbidity are much more likely to receive services than their Canadian counterparts. By contrast, Americans with the lowest incomes and high morbidity are much less likely to receive services for mental health problems than a similar group of Canadians. These results suggest that universal and comprehensive coverage, as exists in Ontario, does not necessarily lead to increased use of services with low value. However, the greater prevalence of perceived need for care among Americans with higher socioeconomic status and low mental morbidity suggests that the United States should be cautious in drawing lessons from other countries.

Adult↗

PubMed1996

Important elements of outpatient care: a comparison of patients' and physicians' opinions.

OBJECTIVE: To compare patients' and physicians' opinions on the importance of discrete elements of health care as determinants of the quality of outpatient care. DESIGN: Analysis of results of a mailed survey. SETTING: Community-based internal medicine practices. PARTICIPANTS: 74 general internists and 814 patients randomly selected from the practices of these internists. MEASURES: 125 elements of care that covered nine domains were identified: physician clinical skill, physician interpersonal skill, support staff, office environment, provision of information, patient involvement, nonfinancial access, finances, and coordination of care. Participants rated each element on its importance to high-quality care on a 4-point scale: 1 = not important; 2 = of medium importance; 3 = of high importance; and 4 = essential. Patients' and physicians' ratings were compared for individual elements of care and for elements aggregated into domains. RESULTS: Survey response rates were 93% for physicians and 60% for patients. In an element-by-element comparison of ratings, ratings by the two groups differed substantially for 58% of the attributes. The most striking difference was seen in the domain of provision of information (median ratings, 3.56 for patients and 2.85 for physicians; P < 0.001). Ratings by the two groups also differed in the domains of clinical skill (3.75 for patients and 3.35 for physicians; P < 0.001), nonfinancial access (3.00 for patients and 2.87 for physicians; P < 0.001), and finances (3.00 for patients and 2.80 for physicians; P = 0.006). When relative rankings of the domains were compared, both groups agreed that clinical skill is most important; however, patients ranked provision of information second in importance whereas physicians ranked it sixth. CONCLUSIONS: Patients and physicians agreed that the most crucial element of outpatient care is clinical skill, but they disagreed about the relative importance of other aspects of care, particularly effective communication of health-related information. These differences in perception may influence the quality of interactions between physicians and patients.

Adolescent↗

PubMed1996

Agoraphobia, simple phobia, and social phobia in the National Comorbidity Survey.

BACKGROUND: Data are presented on the general population prevalences, correlates, comorbidities, and impairments associated with DSM-III-R phobias. METHODS: Analysis is based on the National Comorbidity Survey. Phobias were assessed with a revised version of the Composite International Diagnostic Interview. RESULTS: Lifetime (and 30-day) prevalence estimates are 6.7% (and 2.3%) for agoraphobia, 11.3% (and 5.5%) for simple phobia, and 13.3% (and 4.5%) for social phobia. Increasing lifetime prevalences are found in recent cohorts. Earlier median ages at illness onset are found for simple (15 years of age) and social (16 years of age) phobias than for agoraphobia (29 years of age). Phobias are highly comorbid. Most comorbid simple and social phobias are temporally primary, while most comorbid agoraphobia is temporally secondary. Comorbid phobias are generally more severe than pure phobias. Despite evidence of role impairment in phobia, only a minority of individuals with phobia ever seek professional treatment. CONCLUSIONS: Phobias are common, increasingly prevalent, often associated with serious role impairment, and usually go untreated. Focused research is needed to investigate barriers to help seeking.

Adolescent↗