Showing that life events are a cause of depression--a review

Association of Types of Life Events with Depressive Symptoms among Puerto Rican Youth

The main objective of this study was to examine the association between four types of adverse life events (family environment, separation, social adversity, and death) and the development of depressive symptoms among Puerto Rican youth. This was a secondary analysis using three waves (2000-2004) of interview data from the Boricua Youth Study of 10-13 year old Puerto Rican youth residing in New York and Puerto Rico with no depressive symptoms at baseline (n = 977). Depressive symptoms increased with an increase in social adversity, separation, death, and death events. Youth support from parents was a significant protective factor for all adverse events and parent coping was a protective factor in social adversity events. Relying on standard diagnostic tools is ideal to identify youth meeting the criteria for a diagnosis of depression but not useful to detect youth who present with subclinical levels of depression. Youth with sub-clinical levels of depression will not get treated and are at increased risk of developing depression later in life. Adverse life events are potentially relevant to use in conjunction with other screening tools to identify Puerto Rican youth who have subclinical depression and are at risk of developing depression in later adolescence.

Data collection in studies of life events and the harmful use of alcohol

Although stressful life events have been found to play a role in the development of a number of physical and psychiatric disorders, the research into their influence upon the harmful use of alcohol has been inconsistent. The published studies are reviewed in terms of the methods employed in data collection. It is concluded that a true test of the hypothesis that life events play an aetiological role in the development of the harmful use of alcohol has yet to be carried out, since valid and reliable techniques have not been used in assessing both life events and the onset of harmful use in any one study. Alternative procedures are suggested for use in future research.

Risk factors for depressive symptomatology in a drug using population

This study employs a prospective design to examine possible personality, drug use, stressful life event, and social support-related variables associated with the onset of a depressive episode in a cohort of psychoactive drug using young adults. Two waves of data, collected one year apart, were available on 942 individuals. Cases (n = 62) were free of depressive symptoms at time 1 but reported significant symptomatology at time 2 as measured by the depression subscale of the Brief Symptom Inventory. Controls (n = 490) were those free of depressive symptoms at both time points. In multivariate analyses, users of the central nervous system depressant methaqualone had a nearly four-fold elevated risk for depressed mood as compared to nonusers. Additional risk factors significant after multivariate adjustment included lower self-esteem at time 1 and negative life events. These results highlight the multifactorial nature of depressive symptomatology.

A simplified logic of causal inference

This paper provides a simplified method for evaluating the evidence in favour of a causal claim. It analyses the evidence bearing upon such a claim in terms of two questions: Do the putative cause and effect covary, and can alternative non-causal explanations of the relationship be ruled out? The different research designs for assessing covariation are outlined, as are the ways in which these designs permit a researcher to decide between alternative explanations of the relationship.

Life events and psychiatric disorder: the role of a natural disaster

Examining the impact of natural disasters on psychological health provides an opportunity to study the role played by extreme adversity in the onset of psychiatric disorder. Four hundred and sixty-nine fire-fighters who had been intensely exposed to an Australian bushfire disaster completed a detailed inventory of their experiences four months later. They also completed a brief life events schedule and the 12-item General Health Questionnaire. Only 9% of the GHQ score variance could be accounted for by the disaster and other life events; the effects of the disaster appeared to be separate and additive. This is similar to the relationship between life events and psychiatric illness found in other settings. It is suggested that vulnerability is a more important factor in breakdown than the degree of stress experienced.

Social support, self-esteem and depression

A prospective study of 400 largely working-class women with children living at home has used measures of self-esteem and 'social support' to predict the risk of depression in the following year once a stressor had occurred. Actual support received at the time of any crisis in the follow-up year was also measured. Self-esteem was correlated quite highly with some of the measures of support. A core tie was defined as a husband, lover or someone named as very close at first contact. Negative evaluation of self (i.e. low self-esteem), and various indices of lack of support from a core tie at the first interview, were associated with a greatly increased risk of subsequent depression once a stressor occurred. Lack of support from a core tie at the time of the crisis was particularly highly associated with an increased risk. There was also a high risk among those who were 'let down' - that is, for those who did not receive the support which they might have expected in terms of the first interview material. It is concluded that it is essential for prospective enquiries to take account of the actual mobilization of support in the follow-up period.

The effects of stressful life events and disasters: research and theoretical issues

The study of the relationship between adversity and physical and psychiatric illness can be researched by examining either the effect of multiple random events or the impact of a single event, such as a disaster. There has, however, been little cross-fertilisation of theory or methodology between these two areas of investigation. Disaster research has much to learn from the methodological rigour of life events research. Equally the study of disaster victims can help define the similarities and differences between distress and illness, an issue central to the validity of the concept of 'caseness' in the study of nonpatient samples. In the past, the failure to separate these phenomena may have led to exaggerated estimates of the prevalence of morbidity among disaster victims. It is also important to examine the intervening role played by distress generated by an event in causing physical and psychiatric disorder.