Describing the longitudinal course of major depression using Markov models: data integration across three national surveys (original) (raw)

Markov Chain Model to Explain the Dynamics of Human Depression

Journal of Nonlinear Dynamics, 2014

Depression is one of the major concerns of the present generation. A Markov chain model has been used to portray and investigate this curse. Long-term behaviour of the model has been discussed. Different types of treatment strategies have been considered in this paper to identify the most powerful measure of keeping this disease from its spread in the society. This paper also focuses on the usefulness of the drugs available at present for the treatment of this disease.

A Multistate Transition Model for Analyzing Longitudinal Depression Data

The Bulletin of the Malaysian Mathematical Society Series 2

In longitudinal data analysis, there are many practical situations where we need to deal with transitions to a number of states and which are repeated over time generating a large number of trajectories from the beginning to the end of the study. This problem becomes increasingly difficult to model if the number of follow-ups is increased for a set of longitudinal data. A covariate-dependent Markov transition model is proposed using the logistic link function for polytomous outcome data. A generalized and more flexible approach of constructing the likelihood function for the first or higher order is demonstrated in this paper to deal with the branching of a number of transition types starting from no depression at the beginning of the study. The proposed method can be employed to resolve a longstanding problem in dealing with modeling of transitions, reverse transitions and repeated transitions by reducing the number of trajectories to a large extent, resulting in estimating relativ...

A major depression prognosis calculator based on episode duration

Clinical practice and epidemiology in mental health : CP & EMH, 2006

Epidemiological data have shown that the probability of recovery from an episode declines with increasing episode duration, such that the duration of an episode may be an important factor in determining whether treatment is required. The objective of this study is to incorporate episode duration data into a calculator predicting the probability of recovery during a specified interval of time. Data from two Canadian epidemiological studies were used, both studies were components of a program undertaken by the Canadian national statistical agency. One component was a cross-sectional psychiatric epidemiological survey (n = 36,984) and the other was a longitudinal study (n = 17,262). A Weibull distribution provided a good description of episode durations reported by subjects with major depression in the cross-sectional survey. This distribution was used to develop a discrete event simulation model for episode duration calibrated using the longitudinal data. The resulting estimates were ...

Refining our understanding of depressive states and state transitions in response to cognitive behavioural therapy using latent Markov modelling

Psychological Medicine, 2020

BackgroundIt is increasingly recognized that existing diagnostic approaches do not capture the underlying heterogeneity and complexity of psychiatric disorders such as depression. This study uses a data-driven approach to define fluid depressive states and explore how patients transition between these states in response to cognitive behavioural therapy (CBT).MethodsItem-level Patient Health Questionnaire (PHQ-9) data were collected from 9891 patients with a diagnosis of depression, at each CBT treatment session. Latent Markov modelling was used on these data to define depressive states and explore transition probabilities between states. Clinical outcomes and patient demographics were compared between patients starting at different depressive states.ResultsA model with seven depressive states emerged as the best compromise between optimal fit and interpretability. States loading preferentially on cognitive/affective v. somatic symptoms of depression were identified. Analysis of tran...

Depressive episode characteristics and subsequent recurrence risk

Journal of affective disorders, 2012

BACKGROUND: Clinical practice guidelines increasingly recognize the heterogeneity associated with major depressive episodes (MDE), e.g. through strategies such as watchful waiting. However, the implications of episode heterogeneity for long-term prognosis have not been adequately explored. METHODS: In this project, we used data from a Canadian longitudinal study to evaluate recurrence risks for MDE after an initial episode in the mid-1990s. This study collected data from a community cohort between 1994/1995 and 2008/2009 using biannual interviews. Characteristics of the index episode: syndromal versus sub-syndromal, duration of symptoms, and indicators of seriousness (activity restriction, high distress or suicidal ideation) were recorded. The ability of these variables to predict MDE recurrence was explored using proportional hazards modeling. Additional analyses using generalized estimating equations were used to assess robustness. RESULTS: Even brief, sub-syndromal episodes not c...

Lifetime prevalence estimates of major depression: An indirect estimation method and a quantification of recall bias

European Journal of Epidemiology, 2005

The measurement of lifetime prevalence of depression in cross-sectional surveys is biased by recall problems. We estimated it indirectly for two countries using modelling, and quantified the underestimation in the empirical estimate for one. A microsimulation model was used to generate population-based epidemiological measures of depression. We fitted the model to 1-and 12-month prevalence data from the Netherlands Mental Health Survey and Incidence Study (NEMESIS) and the Australian Adult Mental Health and Wellbeing Survey. The lowest proportion of cases ever having an episode in their life is 30% of men and 40% of women, for both countries. This corresponds to a lifetime prevalence of 20 and 30%, respectively, in a cross-sectional setting (aged 15-65). The NEMESIS data were 38% lower than these estimates. We conclude that modelling enabled us to estimate lifetime prevalence of depression indirectly. This method is useful in the absence of direct measurement, but also showed that direct estimates are underestimated by recall bias and by the cross-sectional setting.

Recurrence in major depression: A conceptual analysis": Correction to Monroe and Harkness (2011)

Psychological Review, 2011

Theory and research on major depression have increasingly assumed a recurrent and chronic disease model. Yet not all people who become depressed suffer recurrences, suggesting that depression is also an acute, time-limited condition. However, few if any risk indicators are available to forecast which of the initially depressed will or will not recur. This prognostic impasse may be a result of problems in conceptualizing the nature of recurrence in depression. In the current paper we first provide a conceptual analysis of the assumptions and theoretical systems that presently structure thinking on recurrence. This analysis reveals key concerns that have distorted views about the long-term course of depression. Second, as a consequence of these theoretical problems we suggest that investigative attention has been biased toward recurrent forms of depression and away from acute, time-limited conditions. Third, an analysis of how these theoretical problems have influenced research practices reveals that an essential comparison group has been omitted from research on recurrence: people with a single lifetime episode of depression. We suggest that this startling omission may explain why so few predictors of recurrence have as yet been found. Finally, we examine the reasons for this oversight, document the validity of depression as an acute, time-limited disorder, and provide suggestions for future research with the goal of discovering early risk indicators for recurrent depression.

Simulation studies of age-specific lifetime major depression prevalence

BMC Psychiatry, 2010

Background: The lifetime prevalence (LTP) of Major Depressive Disorder (MDD) is the proportion of a population having met criteria for MDD during their life up to the time of assessment. Expectation holds that LTP should increase with age, but this has not usually been observed. Instead, LTP typically increases in the teenage years and twenties, stabilizes in adulthood and then begins to decline in middle age. Proposed explanations for this pattern include: a cohort effect (increasing incidence in more recent birth cohorts), recall failure and/or differential mortality. Declining age-specific incidence may also play a role. Methods: We used a simulation model to explore patterns of incidence, recall and mortality in relation to the observed pattern of LTP. Lifetime prevalence estimates from the 2002 Canadian Community Health Survey, Mental Health and Wellbeing (CCHS 1.2) were used for model validation and calibration.