Biomedical subjects

Scott B Patten

Publications and source records attributed to Scott B Patten.

66 records · Page 4Linked to original sources

PubMed2002

Progress against major depression in Canada.

BACKGROUND: Generally, public health strategies for major depression have focused on case-finding, public and professional education, and disease-management strategies. In principle, increased rates of treatment utilization and improved treatment outcomes should lead to improved mental health at the population level. Progress of this sort, however, has been difficult to confirm. METHODS: The National Population Health Survey (NPHS) is a large-scale longitudinal study of a representative sample drawn from the Canadian population. To date, Statistics Canada has released data from 3 NPHS cycles: 1994-1995, 1996-1997, and 1998-1999. Treatment utilization and major depression measures were employed in the NPHS survey, providing a unique source of longitudinal Canadian data. In this study, major depression point prevalence (defined using a predictive instrument for annual major depressive episode [MDE] prevalence and responses from a distress scale) and associated treatment utilization were evaluated over time. RESULTS: Between 1994-1995 and 1995-1996, the proportion of persons with depression receiving antidepressant treatment increased dramatically, from 18.2% (12.3% to 22.1%) in 1994-1995 to 32.6% (23.0% to 42.2%) in 1998-1999. Point prevalence of major depression was 2.4%, 1.8%, and 1.9% in the 3 NPHS iterations. CONCLUSIONS: Data from the NPHS suggest public health progress against major depression in Canada. More people with major depression in Canada are receiving treatment, and these changes may have been associated with improved population health status. However, both random variation and extraneous societal factors could account for the observed trends in prevalence. It is impossible to relate changes in utilization directly to population health status using the NPHS data.

Antidepressive Agents↗

PubMed2002

Major depressive episodes and diet pills.

A variety of medications used to assist with weight loss have been implicated in the precipitation or induction of depressive symptoms and disorders. This is true of a large number of phenylethylamine agents possessing psychostimulant properties, non-phenylethylamine psychostimulants (e.g., caffeine) and the serotonergic agent, fenfluramine. There is, as yet, no substantial evidence linking the more modern weight loss drugs, sibutramine and orlistat, to the aetiology of major depression. Nevertheless, when these drugs are used, major depression will continue to be an important clinical consideration because of the elevated frequency with which major depression occurs in obese patients, the contribution that major depression may make to poor outcomes in non-pharmacological weight loss treatment and because of the interplay between symptoms of depression and weight loss treatment.

Anti-Obesity Agents↗

PubMed2002

Hopelessness ratings in relapsing-remitting and secondary progressive multiple sclerosis.

OBJECTIVE: Two recent randomized double-blind placebo controlled clinical trials of interferon beta-1a in multiple sclerosis have obtained hopelessness ratings using the Beck Hopelessness Scale (BHS). One of these studies, the PRISMS trial, evaluated interferon beta-1a in relapsing remitting multiple sclerosis (RRMS). Another, the SPECTRIMS trial, evaluated the same medication in secondary progressive (SP) MS. The objective of this analysis was to compare levels of hopelessness in persons with RRMS and SPMS, and to describe changes over time in the clinical trial participants. METHOD: Raw data from each clinical trial was obtained from the sponsor of the trials (Serono). Median BHS ratings, and the proportions at or above the BHS cut-point of 10 were calculated over a two (PRISMS) or three (SPECTRIMS) year period. RESULTS: The analysis included n = 532 clinical trial participants. Ratings of hopelessness were higher in SPMS clinical trial participants (SPECTRIMS) than in the RRMS group (PRISMS) at baseline (Fisher's exact test, p = 0.0035). Furthermore, ratings of hopelessness were higher during follow-up than at baseline, in the SPMS group (McNemar's exact probability,p = 0.0015), but not in the RRMS group (McNemar's exact probability,p = 0.65). Depression was strongly associated with hopelessness in both RRMS (z = 4.13, p < 0.001) and SPMS (z = 5.24, p < 0.001). CONCLUSIONS: Hopelessness is associated with SPMS, and may increase over time in this group. Hopelessness may influence suicide risk in people with MS and may potentially have an impact on coping and quality of life. Additional research is necessary to define the clinical implications of hopelessness in persons with this condition.

Adult↗

PubMed2002

Major depressive disorder and health care costs in multiple sclerosis.

OBJECTIVE: Multiple Sclerosis (MS) is associated with elevated levels of depressive symptoms and an elevated frequency of depressive disorders. Depressive disorders, in general, are associated with substantial direct and indirect economic costs, and have been shown to increase the costs associated with the management of medical conditions in a variety of clinical settings. However, the impact of depressive disorders on costs associated with MS have not been evaluated. The objective of this study was to evaluate this association. METHODS: The Composite International Diagnostic Interview (CIDI) was used to identify subjects with major depressive disorder in a sample who had earlier been selected for a broader economic evaluation of the costs associated with MS. Costs were measured in two ways: retrospectively (by questionnaire covering a 2-year period) and prospectively (using a 6-month diary). The proportion of subjects reporting any costs and the proportion exceeding various cost thresholds were calculated in subjects with and without lifetime major depression. These proportions were compared using exact statistical tests and confidence intervals. Non-parametric (rank sum) tests were used to compare median costs. RESULTS: Of 136 subjects, 31 had a lifetime history of major depression. MS-related expenses evaluated retrospectively (e.g., house and vehicle alterations and purchases) did not differ depending on major depression status. In the prospective analysis, subjects with lifetime major depression were more likely to purchase vitamins, herbs, and naturopathic remedies (p < 0.01) and more likely to incur costs associated with utilization of services provided by alternative practitioners (p = 0.04). Other differences (e.g., in mental health care, medical specialists, general practitioner visits) were not observed. CONCLUSIONS: Contrary to expectation, this study did not find increased direct medical costs in persons with comorbid major depressive disorder and multiple sclerosis. Persons with comorbid MS and (lifetime) major depression did not incur greater costs or utilize more services. The Canadian health care system is guided by principles of universality and is publicly funded and administered, however, the lack of an impact of major depression on utilization may reflect limited access to services. The lack of an association between costs and major depression may or may not be generalizable to health care systems in other countries.

Adult↗

PubMedDate not supplied

A framework for describing the impact of antidepressant medications on population health status.

BACKGROUND: In the absence of strategies for primary prevention, public health initiatives for major depression have generally focused on secondary and tertiary strategies such as case-finding, public and professional education and disease management. Much emphasis has been placed on low reported rates of antidepressant utilization. In principle, increased rates of treatment utilization should lead to improved mental health status at the population level. However, methods for relating antidepressant utilization to population health status have not been described. METHODS: An incidence-prevalence model was developed using data from a Canadian national survey, supplemented by parameter estimates from literature reviews. The lifetime sick-day proportion (LSP) was used to approximate point prevalence. RESULTS: Mathematical simulations using this model produced reasonable approximations of point prevalence for major depression. The model suggests that an improved rate of treatment utilization may not, in itself, lead to substantially reduced prevalence. Reducing the rate of relapse in those with highly recurrent disorders, which can be accomplished by long-term antidepressant treatment, is predicted to have a more substantial impact on population health status. CONCLUSIONS: The model presented here offers a framework for describing the impact of antidepressant treatment on population health status. Mathematical models may assist with decision-making and priority setting in the public health sphere, as illustrated by the model presented here, which challenges some commonly held assumptions.

Antidepressive Agents↗

PubMedDate not supplied

Adjustment to antidepressant utilization rates to account for depression in remission.

Conventional estimates of antidepressant (AD) utilization in major depressive syndrome (MDS) have been low, but this may be partially because ongoing AD use by individuals with resolved MDS is not included. Valid estimates of AD utilization should include this ongoing use for MDS, but this is difficult since most surveys do not collect data on the reason for taking ADs. Only a proportion (f(dep)) of the nondepressed (nMDS) population taking ADs does so for depression. Published studies have not reported this proportion, and data required to estimate f(dep) are not usually available from surveys. The current study was performed to (1) estimate f(dep) by employing information on past history of depression, and (2) use the estimate to obtain an "adjusted" AD utilization rate, including resolved MDS subjects taking ADs. Data were collected in Calgary in 1998 and 1999 by random-digit dial telephone interview from consenting adults aged 18+ years. MDS was assessed using the Composite International Diagnostic Interview Short Form for Major Depression (CIDI-SFMD). Data were gathered on current medications, past depression, and current chronic physical illness. Of 2,542 respondents, 17.1% had MDS as defined by the CIDI-SFMD. A total of 20.2% of MDS and 3.2% of nMDS subjects were taking ADs. Of nMDS individuals taking ADs, 70.6% reported past depression (f(dep) = 70.6%). An "adjusted" AD utilization rate including this group was 28.2%. Physical illnesses that can be treated with ADs affected only 30.0% of nMDS subjects without past depression taking ADs. This study suggests that most individuals without active depression taking ADs do so for depression. AD utilization rates that ignore this group may be unrealistically low. AD use among nMDS subjects without previous depression is probably not primarily for physical illnesses. Limitations include the use of a brief predictive instrument for MDS, and self-report of past depression.

Adolescent↗

PubMedDate not supplied

Clinical correlates of CES-D depressive symptom ratings in an MS population.

OBJECTIVE: In multiple sclerosis (MS), depression rating scales may be used as case-finding instruments for depressive disorders, but depressive symptom ratings may have clinical implications beyond their case-finding role. The objective of this analysis was to explore this possibility by carrying out descriptive analyses of symptom ratings obtained using the Center for Epidemiological Studies Depression Rating Scale (CES-D) in an MS clinic population. METHOD: The analysis used cross-sectional baseline data collected from 589 subjects enrolled in a prospective cohort study. Data collection included demographic and clinical information including Extended Disability Status Scale ratings, a 54-item MS Quality of Life Scale and the Fatigue Impact Scale. RESULTS: Across a spectrum of CES-D scores, correlations with other health indicators were observed. Depressive symptoms were higher in more disabled subjects. CES-D scores were correlated with the emotional well-being dimension of quality of life and with a social fatigue impact dimension. Alternative scoring of the CES-D had a negligible impact on the pattern of correlation. CONCLUSIONS: CES-D ratings appear to be interpretable beyond the traditional yes/no categorization used in case finding. CES-D ratings are predictive of other clinical parameters in domains relevant to mental health.

Alberta↗

PubMedDate not supplied

Self-reported thyroid disease and mental disorder prevalence in the general population.

OBJECTIVE: Community studies have failed to confirm that biochemically assessed thyroid status is significantly associated with psychopathology. However, it has been reported that self-reported thyroid disease is associated with symptoms of depression and anxiety. The objective of the current study was to determine whether self-reported thyroid disease is associated with elevated mental disorder prevalence in the general population. METHOD: Data from the Canadian Community Health Survey (CCHS) 1.2: Mental Health and Well-being were used. The CCHS 1.2 included the World Mental Health version of the Composite International Diagnostic Interview and collected self-report data about professionally diagnosed chronic medical conditions, including thyroid disease. RESULTS: Twelve-month and lifetime mental disorder prevalence was higher in subjects with thyroid disease than in subjects reporting no chronic conditions. For each condition examined (major depressive disorder, bipolar disorder, panic disorder/agoraphobia and social phobia), the 12-month and lifetime prevalence in subjects with thyroid disease resembled that of an aggregate category of subjects having other chronic conditions. After adjustment for age, sex and other chronic conditions, only social phobia was found to be associated with thyroid disease. CONCLUSIONS: People with thyroid disease are not a particularly high-need group for mental disorder screening or intervention, at least not in the community population.

Adolescent↗

PubMedDate not supplied

Towards a dynamic description of major depression epidemiology.

AIMS: The substantial impact of major depression on population health is widely acknowledged. To date, health system responses to this condition have been largely shaped by observational findings. In the future, health policy decisions will benefit from an increasingly integrated and dynamic understanding of the epidemiology of this condition. Policy decisions can also be supported by the development of decision-support tools that can simulate the impact of alternative policy decisions on population health. Markov models are useful both in epidemiological modelling and in decision analysis. METHODS: In this project, a Markov model describing major depression epidemiology was developed. The model employed a Markov Tunnel in order to depict the dependence of recovery probabilities on episode duration. Transition probabilities, including incidence, recovery and mortality were estimated from Canadian national survey data. RESULTS: Episode incidence was approximately 3% per year. Recovery rates declined exponentially over time. The model predicted point prevalence at slightly less than 1%, agreeing closely with observed prevalence data. CONCLUSIONS: Epidemiological models describing the dynamic relationships between major depression incidence, prevalence, recovery and mortality can help to integrate available epidemiological data. Such models offer an attractive option for support of health policy decisions.

Adolescent↗

PubMedDate not supplied

Drug-induced depression: a systematic review to inform clinical practice.

BACKGROUND: Certain medications may contribute to the etiology of depressive symptoms and disorders. Research in this area, however, has been hampered by methodological and conceptual problems. This review had two objectives: to identify evidence linking medical drugs to depressive symptoms and disorders, and to summarize this evidence in a clinically meaningful way. METHODS: Electronic literature searches were performed and studies were reviewed with reference to critical methodological features. RESULTS: No medications causing the typical major depressive syndrome were identified. Evidence was found linking corticosteroids, interferon-alpha, interleukin-2, gonadotropin-releasing hormone agonists, mefloquine, progestin-releasing implanted contraceptives and propranolol to the etiology of atypical depressive syndromes. CONCLUSIONS: A small number of drugs have been shown capable of inducing depressive symptoms. Drug-induced depression appears to differ symptomatically from classical major depression.

Adrenal Cortex Hormones↗

PubMedDate not supplied

Predictive value of the CES-D in detecting depression among candidates for disease-modifying multiple sclerosis treatment.

The presence of depression is an important concern for patients with multiple sclerosis who are candidates for disease-modifying treatment, since depression may affect treatment adherence. The authors evaluated the positive predictive value of the Center for Epidemiologic Studies Depression Rating Scale (CES-D) in detecting depression among patients who were candidates for disease-modifying multiple sclerosis treatment. Of 47 patients who scored >/=16 on the CES-D, 74.5% (N=38) were found to have a depressive disorder. The results of the study indicate that case-finding for depressive disorders among multiple sclerosis patients can be facilitated by use of the CES-D scale.

Adolescent↗

PubMedDate not supplied

Refining estimates of major depression incidence and episode duration in Canada using a Monte Carlo Markov model.

BACKGROUND: Serial period prevalence estimates for recurrent diseases such as major depression are available more frequently than fully detailed longitudinal data, but it is difficult to estimate incidence and episode duration from such data. Incidence and episode duration are critical decision modeling parameters for recurrent diseases. OBJECTIVES: To reduce bias that would otherwise occur in national incidence and duration-of-episode estimates for major depressive episodes deriving from studies using serial period prevalence data and to illustrate a methodological approach for the estimation of incidence from such studies. METHODS: Monte Carlo simulation was applied to a Markov process describing incidence and recovery from major depressive episodes. RESULTS: The annual incidence and episode duration were found to be 3.1% and 17.1 weeks, respectively. These estimates are expected to be less subject to bias than those generated without modeling. CONCLUSIONS: These results highlight the usefulness of Markov models for analysis of longitudinal data. The methods described here may be useful for decision modeling and may be generalizable to other chronic diseases.

Canada↗