The relationship between mood instability and depression: implications for studying and treating depression.

BACKGROUND: Most individuals with depressed mood report mood fluctuations (Mood Instability) within hours or days. This is not recognized in diagnostic criteria or standard rating scales for depression. HYPOTHESIS: That mood instability is a distinct component of the development of depression that has been omitted from criteria for depression because of reliance on retrospective recall and structured interviews. The inclusion of Mood Instability would enhance research into causes and treatment of depression. STUDIES: We examined three datasets that used retrospective and prospective measures of depressed symptom ratings and mood instability to determine the relationship between the two. Study 1 used data from the 1991 UK Health and Lifestyle Surveys (HALS). Studies 2 and 3 used clinical samples. The scales used to assess mood instability were the mood instability factor from the Eysenck Personality Inventory Neuroticism Scale, the Affective Lability Scale (ALS), and the Visual Analogue Depression Scale (VAS). The depression scales (depressive symptoms) were the General Health Questionnaire (GHQ) depression factor, the Beck Depression Inventory IA (BDI) and the mean from the Visual Analogue Depression Scale (VAS). We used partial correlation analysis to assess the association between mood instability and depression and exploratory factor analysis to determine the factor structure of items pooled from the mood instability and depression scales from studies 1 and 2. RESULTS: Mood Instability was found to be moderately associated with depressive symptoms. The Pearson's r-values ranged from 0.49 to 0.57. The correlation was lower when recalling mood in the past. The factor analytic solution supported the hypothesis that MI and depressive symptoms are related but distinct constructs. CONCLUSIONS: Reliance exclusively on the retrospective assessment of depressive symptoms has occluded the widespread occurrence of mood instability. Including Mood Instability in diagnostic and assessment criteria would enhance causal and treatment research in depression.

Antenatal depression in socially high-risk women in Canada.

BACKGROUND: Antenatal depression is potentially deleterious to the mother and baby. Canadian Aboriginal women have an increased risk for living in poverty, family violence, and substance use; however, little is known about antenatal depression in this group. The aim of this study was to determine the prevalence and correlates of depression in socially high-risk, mostly Aboriginal pregnant women. METHODS: Women (Aboriginal and non-Aboriginal), in two prenatal outreach programmes were approached and depressive symptoms between the two groups were compared, using the Edinburgh Postnatal Depression Scale (EPDS). RESULTS: Sixty per cent (n = 402) of potential participants were recruited for the study. The prevalence of depression was 29.5% (n = 402). Depression was associated with a history of depression, mood swings, increased stressors, current smoker, and lack of social support. Aboriginal women were more likely to be depressed, but this was not significantly higher than non-Aboriginal women; however, they did experience significantly more self-harm thoughts. Exercise was a significant mediator for depression. CONCLUSION: The prevalence of antenatal depression confirms rates in other high-risk, ethnic minority groups of women. A previous history of depression and mood problems were associated with depression, thus prenatal care should include a careful mental health assessment. On a positive note, the present study suggests that exercise may mediate antenatal depression.

Chronic pain and fatigue: Associations with religion and spirituality.

BACKGROUND: Conditions with chronic, non-life-threatening pain and fatigue remain a challenge to treat, and are associated with high health care use. Understanding psychological and psychosocial contributing and coping factors, and working with patients to modify them, is one goal of management. An individual's spirituality and/or religion may be one such factor that can influence the experience of chronic pain or fatigue. METHODS: The Canadian Community Health Survey (2002) obtained data from 37,000 individuals 15 years of age or older. From these data, four conditions with chronic pain and fatigue were analyzed together -- fibromyalgia, back pain, migraine headaches and chronic fatigue syndrome. Additional data from the survey were used to determine how religion and spirituality affect psychological well-being, as well as the use of various coping methods. RESULTS: Religious persons were less likely to have chronic pain and fatigue, while those who were spiritual but not affiliated with regular worship attendance were more likely to have those conditions. Individuals with chronic pain and fatigue were more likely to use prayer and seek spiritual support as a coping method than the general population. Furthermore, chronic pain and fatigue sufferers who were both religious and spiritual were more likely to have better psychological well-being and use positive coping strategies. INTERPRETATION: Consideration of an individual's spirituality and/or religion, and how it may be used in coping may be an additional component to the overall management of chronic pain and fatigue.

Effect of high versus low ambient humidity on the severity of obstructive sleep apnoea.

BACKGROUND: Surface tension forces appear to make a significant contribution to upper airway closure in patients with obstructive sleep apnoea (OSA). It is possible that drying of the upper airway mucosa at night might contribute to these surface tension forces and the severity of OSA might therefore change with alteration of the ambient humidity. METHODS: A randomised single blind crossover study of high ambient relative humidity (HRH) versus low ambient relative humidity (LRH) was performed in 12 men of mean (SD) age 49 (9) years with mild OSA (apnoea/hypopnoea index (AHI) 14 (5.2)). On one night patients slept in continuous HRH (85 (4)%, range 80-93%) and on the other in LRH (16 (4)%, range 11-22%). RESULTS: The AHI was similar on the HRH and LRH nights (mean difference 3; 95% CI -2 to 9, p = 0.20 and no statistically significant differences in AHI were observed on the two nights after standardising for body position and sleep stage. Sleep stage distribution and the proportion of time spent in the supine position were similar on the HRH and LRH nights. The number of non-respiratory arousals was also similar on the two nights. CONCLUSION: Altering ambient humidity alone has no significant impact on the severity of OSA.

Efficacy of divalproex sodium in patients with panic disorder and mood instability who have not responded to conventional therapy.

OBJECTIVE: To determine the efficacy of divalproex sodium in the treatment of psychiatric outpatients with treatment refractory panic disorder and comorbid mood instability. METHOD: This was an 8-week, open-trial, flexible-dose outcome study conducted at a tertiary care referral centre. Individuals with panic disorder who failed to respond to a cognitive behavioural treatment program and standard antipanic medication, who also suffered from mood instability, were chosen to participate in the study. Divalproex sodium was administered at a flexible dose to reach serum levels of 300 to 600 mumol/L (45 to 90 ug/ml) unless limited by tolerance. Patients were rated by self- and rater-administered questionnaires that measured the number of panic attacks, the degree of agoraphobic avoidance, the levels of depression, anxiety, and mood swings, and the perceived sense of well being. RESULTS: Thirteen subjects were enrolled in the study, and 10 subjects completed it. Two dropped out early because of the medication's side effects, and 1 was lost within the first month of follow-up. All 10 subjects showed significant improvement in depressive and anxiety symptoms and mood instability. There was also a statistically and clinically significant improvement in panic attacks and measures of quality of life. CONCLUSIONS: These findings suggest that divalproex sodium is useful in the treatment of patients with panic disorder and concomitant mood instability, who are refractory to conventional treatment. Double-blind trials will be required to verify these findings.

Effect of body positions and splints in bioelectrical impedance analysis.

The objective of this study was to evaluate body composition as measured by bioelectric impedance analysis using splints and body positions differing from the standard supine position. Forty-three patients, randomized into two groups of different body positions, and 101 healthy volunteers were prospectively studied. Resistance and reactance of body tissues were measured by bioelectric impedance analysis. Body composition is described by a three-compartment model composed of body fat, body cell mass, and extra cellular mass. The patients were measured in the standard supine position and then randomized into two groups. They were then remeasured with the appropriate splinting device or position change. Volunteers were measured in the standard supine position and all four alternative positions. There was a statistically significant difference demonstrated in whole body resistance, whole body reactance, body cell mass, and the ratio of extracellular mass to body cell mass in some body positions. The percentage of change with different body positions and splints, when compared with the standard supine position, was generally below 2%, a clinically insignificant difference. We conclude that the reliability of resistance and reactance as measured by bioelectric impedance analysis is clinically valid using any of the tested body positions and/or splints. The three-compartment model may be a useful concept to measure body composition changes in both healthy and sick persons.