Kate L. Harkness

Specificity in the Relations among Childhood Adversity, Early Maladaptive Schemas, and Symptom Profiles in Adolescent Depression

The present cross-sectional study examined the relations of particular forms of childhood adversity (e.g., emotional maltreatment vs. physical abuse vs. sexual abuse) to specific early maladaptive schema themes (e.g., worthlessness/loss vs. danger) and symptom profiles (i.e., anhedonic vs. anxious). Seventy-six depressed adolescents retrospectively reported on their childhood experiences of emotional maltreatment, physical abuse, and sexual abuse in a contextual semi-structured interview. They were also administered the Young Schema Questionnaire to measure early maladaptive schemas, and the Mood and Anxiety Symptom Questionnaire to measure anhedonic and anxious symptomatology. Consistent with specificity hypotheses, schemas with themes of loss/worthlessness preferentially mediated the relation between childhood adversity and anhedonic symptoms, while schemas with themes of danger preferentially mediated the relation between childhood adversity and anxious symptoms. Sexual abuse was not significantly associated with either depression or anxiety symptoms and, thus, mediation models involving sexual abuse were not tested. Implications for fine-grained models of etiology in depression are discussed.

Cortisol reactivity to social stress in adolescents: Role of depression severity and child maltreatment

This study examined the hypothesis that depressed adolescents with a history of childhood maltreatment will show greater cortisol reactivity to psychological stress challenge than those without, and this relation will be moderated by level of depression severity. Seventy-one adolescents were exposed to the Trier Social Stress Test. Salivary cortisol was assessed at baseline, immediately before the challenge, after the challenge, and during an extended recovery period. Childhood maltreatment was assessed with a rigorous contextual interview and rating system. Adolescents with a history of maltreatment produced higher and more prolonged levels of cortisol in response to the challenge than did adolescents with no maltreatment, but only among those with a mild/moderate level of depression severity. Those with moderate/severe depression exhibited a blunted cortisol response regardless of child maltreatment history. These findings indicate that depression is a heterogeneous syndrome, and that both depression severity and child maltreatment history should be considered in studies examining biological stress reactivity.

The generation of life events in recurrent and non-recurrent depression

BACKGROUND The stress generation hypothesis proposed by Hammen (1991) holds that depressed individuals generate stressful conditions for themselves, which lead to recurrence. The original test of this hypothesis compared dependent life events in women with recurrent depression to medical and normal controls. Two further research questions emerged from this work: (a) do individuals with a history of many depressive episodes generate more dependent life events than depressives with fewer episodes?; and (b) what is the aetiological relevance of any stress that may be generated? METHODS The present research tested differences in dependent and independent events between depressed individuals who had experienced: (a) no previous major depressive episodes; (b) one previous episode; and (c) two or more previous episodes. We predicted that, based on the stress generation hypothesis, recurrent depressives would show more dependent events than people without a depression history, and that these generated stressors would be of aetiological importance for precipitating recurrence (i.e. severe events in the 3 months preceding recurrence). RESULTS Recurrent depressives experienced significantly more total dependent events than first-onset depressives in the 12 months, but not the 3 months, preceding their episode. CONCLUSIONS Although the findings supported the general premise of stress generation, the aetiological relevance of the generated stress for recurrence requires further study.

Repeated exposure to stress across the childhood-adolescent period alters rats' anxiety- and depression-like behaviors in adulthood: The importance of stressor type and gender.

This research tests the hypothesis that specific forms of adversity in early life map onto behavioral signs analogous to depression versus anxiety in later life. Male and female rats were exposed to either severe sporadic stress or chronic mild stress during the childhood-adolescent period, and their behavior was tested in adulthood. Males in the severe sporadic stress group showed exaggerated anxiety-related behaviors, as indicated by increases in shock-probe burying and escape-like responses (jumps) from the open arms of the elevated plus-maze. Females exposed to severe sporadic stress displayed no change in burying behavior but did display increases in escape behavior. These same females also exhibited behaviors analogous to depression that manifested as decreased sucrose consumption. The chronic mild stress regime produced effects only in females, including reduced burying, decreased sucrose consumption, and an exaggerated corticosterone response to cold-water immersion stress. Findings reiterate the importance of early life experience to the development of adult psychopathologies and emphasize the need to consider both the type of early experience and gender differences in these analyses.

Recurrence in Major Depression: A Conceptual Analysis.

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.

Gender Differences in Life Events Prior to Onset of Major Depressive Disorder: The Moderating Effect of Age

Theoretical models attempting to explain why approximately twice as many women as men suffer from depression often involve the role of stressful life events. However, detailed empirical evidence regarding gender differences in rates of life events that precede onset of depression is lacking, due in part to the common use of checklist assessments of stress that have been shown to possess poor validity. The present study reports on a combined sample of 375 individuals drawn from 4 studies in which all participants were diagnosed with major depressive disorder and assessed with the Life Events and Difficulties Schedule (Bifulco et al., 1989), a state-of-the-art contextual interview and life stress rating system. Women reported significantly more severe and nonsevere, independent and dependent, and other-focused and subject-focused life events prior to onset of depression than did men. Further, these relations were significantly moderated by age, such that gender differences in rates of most types of events were found primarily in young adulthood. These results are discussed in term of their implications for understanding the etiological role of stressful life events in depression.

Seasonal and non-seasonal depression and the five-factor model of personality

The purpose of this study was to compare the personality characteristics of patients with non-psychotic, major depression, seasonal subtype (SAD) to patients with non-psychotic, major depression, without seasonality (non-SAD). The patients were consecutive referrals to a university-affiliated mood disorders outpatient clinic. The personality characteristics were assessed using the five-factor model of personality (FFM) as measured by the revised NEO Personality Inventory (NEO PI-R). Patients were assessed during the acute depressive episode. Controlling for severity of depression, differences were found on only one of the five dimensions, with the SAD patients (n = 43) scoring significantly higher on the Openness dimension than non-SAD patients (n = 57). Based on these results we infer SAD patients may represent a psychologically distinct subgroup of depressed patients-more imaginative, more emotionally sensitive and likely to entertain unconventional ideas than non-SAD patients. This personality constellation may explain why individuals with SAD are more sensitive to and may amplify the mild dysphoria typically associated with winter months.

Parental Maltreatment, Bullying, and Adolescent Depression: Evidence for the Mediating Role of Perceived Social Support.

The support deterioration model of depression states that stress deteriorates the perceived availability and/or effectiveness of social support, which then leads to depression. The present study examined this model in adolescent depression following parent-perpetrated maltreatment and peer-perpetrated bullying, as assessed by a rigorous contextual interview and rating system. In 101 depressed and nondepressed community adolescents between the ages of 13 and 18 (M = 15.51, SD = 1.27), peer bullying and father-perpetrated maltreatment were associated with lower perceptions of tangible support and of belonging in a social network. These forms of support mediated the association of bullying and father-perpetrated maltreatment with greater depression severity. In contrast, mother-perpetrated maltreatment was associated with higher perceptions of tangible support.

Life stress and the symptoms of major depression.

Life stress has been found to be associated with onset of depression and with greater severity of depressive symptoms. It is unclear, though, if life stress is related to particular classes or specific symptoms in depression. The association between severe life events and depressive symptoms was tested in 59 individuals diagnosed by Research Diagnostic Criteria with endogenous primary nonpsychotic major depression. As predicted, life stress was associated principally with cognitive-affective symptoms, not somatic symptoms. There also was a consistent association across different assessment methods between severe events and suicidal ideation. Finally, associations held specifically for severe events occurring before onset, not for severe events occurring after onset. Symptom variation in major depression is related specifically to severe stressors before onset and includes primarily cognitive-affective types of symptoms. There is an especially pronounced association of prior severe stress with suicidal ideation. The implications of stress-symptom associations are addressed for enlarging understanding of symptom heterogeneity and subtype distinctions in major depression.

Major depression, chronic minor depression, and the five-factor model of Personality

Fifty‐eight outpatients with major depression completed the NEO Personality Inventory at intake (time 1) and after up to three months of anti‐depressant treatment (time 2). Within this group, 26 patients met additional Research Diagnostic Criteria for chronic minor depression. Repeated‐measures analyses revealed significant decreases in Neuroticism scores, and significant increases in Extraversion and Conscientiousness scores, from time 1 to time 2 for both patient groups. In addition, despite similar symptom severity at time 2, the patients with major depression+chronic minor depression scored significantly higher on the Angry Hostility facet of Neuroticism and significantly lower on Agreeableness than those with major depression alone. We suggest from these findings that Angry Hostility and low Agreeableness may represent a trait vulnerability in individuals with chronic minor depression that persists even following remission of the major depressive state, and that this may help to explain their high rates of relapse and recurrence. Copyright