Exercise as an augmentation treatment for nonremitted major depressive disorder: a randomized, parallel dose comparison

OBJECTIVE

Most patients with major depressive disorder (MDD) require second-step treatments to achieve remission. The Treatment with Exercise Augmentation for Depression (TREAD) study was designed to test the efficacy of aerobic exercise as an augmentation treatment for MDD patients who had not remitted with antidepressant treatment.

METHOD

Eligible participants in this randomized controlled trial were sedentary individuals (men and women aged 18-70 years) diagnosed with DSM-IV nonpsychotic MDD who had not remitted with selective serotonin reuptake inhibitor (SSRI) treatment. Participants were recruited through physician referrals and advertisements. A total of 126 participants were randomized to augmentation treatment with either 16 kcal per kg per week (KKW) or 4 KKW of exercise expenditure for 12 weeks while SSRI treatment was held constant. Supervised sessions were conducted at The Cooper Institute, Dallas, Texas, with additional home-based sessions as needed to fulfill the weekly exercise prescription. The primary outcome was remission (as determined by a score ≤ 12 on the Inventory of Depressive Symptomatology, Clinician-Rated). The study took place between August 2003 and August 2007.

RESULTS

There were significant improvements over time for both groups combined (F₁,₁₂₁ = 39.9, P < .0001), without differential group effect (group effect: F₁,₁₃₄ = 3.2, P = .07; group-by-time effect: F₁,₁₁₉ = 3.8, P = .06). Adjusted remission rates at week 12 were 28.3% versus 15.5% for the 16-KKW and 4-KKW groups, respectively, leading to a number needed to treat (NNT) of 7.8 for 16 KKW versus 4 KKW. Men, regardless of family history of mental illness, and women without a family history of mental illness had higher remission rates by week 12 with higher-dose (women, 39.0%; men, 85.4%) than with lower-dose exercise (women, 5.6%; men, 0.1%) (women: t₉₅ = 2.1, P = .04; men: t₈₈ = 5.4, P < .0001) (NNT: women, 3.0; men, 1.2).

CONCLUSIONS

There was a trend for higher remission rates in the higher-dose exercise group (P < .06), with a clinically meaningful NNT of 7.8 in favor of the high exercise dose. Significant differences between groups were found when the moderating effects of gender and family history of mental illness were taken into account and suggest that higher-dose exercise may be better for all men and for women without a family history of mental illness.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00076258.

Defining and measuring functional recovery from depression

Depression is associated with significant functional impairment and reduced quality of life. Disruptions occur both globally as well as in specific functional areas such as work, interpersonal relationships and cognitive function. From both a clinical and research perspective, much focus has been given to the resolution of symptoms associated with depression, while relatively little attention has been given to functional improvements. Definitions of remission in depression are most frequently based on achieving a cut-off score on clinical rating scales of depressive symptoms. Research in this area has sparsely included psychosocial function or health-related quality of life as a primary outcome measure in clinical trials. However, the need to fully understand the impact of depression and its treatments on functioning is great, given the existing evidence of the profound effect that depression has on function. Even mild depressive symptoms and subsyndromal depression result in functional impairment and reduced quality of life, and untreated residual depressive symptomatology can result in an increased likelihood for relapse of the fully symptomatic disorder (i.e. major depressive disorder). Therefore, clinicians and researchers alike need to broaden the focus of treatment to encompass not only the specific symptoms of depression, but the functional consequences as well. Many tools have been developed to assess function and quality of life, both globally as well as within specific domains. In addition, the effect of residual symptoms associated with functional impairment (i.e. insomnia, fatigue, pain [somatic] symptoms and cognition) in depression, even independently of depressive symptoms, warrants evaluation and monitoring. Recommendations for evaluating functional outcomes include: (i) adequately assessing functional impairment; (ii) identifying and/or developing treatment plans that will target symptoms associated with functional impairments; and (iii) monitoring functional impairments and associated symptoms throughout the course of treatment. The development of treatments that specifically target improvements in functional impairments is needed, and may require the use of novel treatment strategies.

Association between depression severity and neurocognitive function in major depressive disorder: a review and synthesis

The effects of major depressive disorder (MDD) on neurocognitive function remain poorly understood. Results from published studies vary widely in terms of methodological factors, and very little is known about the effects of depression severity and other clinical characteristics on neurocognitive function. The purpose of this review was to synthesize prior research findings regarding neurocognitive functioning in patients with MDD and varying levels of depression severity and to provide recommendations for future directions. Overall, this review suggests that MDD has been inconsistently associated with neurocognitive functioning and there is limited understanding regarding the relationship between depression severity and neurocognitive sequelae. There was much heterogeneity on depression severity-related factors across studies assessing neurocognitive function in MDD, as well as substantial variability in the consideration of depression severity among studies, which suggests a need to further explore this important issue.

DATE: Depressed adolescents treated with exercise: Study rationale and design for a pilot study

There is an important need for non-medication interventions for depressed youth. The aim of this study is to evaluate the feasibility of using a standardized aerobic exercise regime to treat non-medicated clinically depressed adolescents based on adherence and completion rates, including 1) establishing effect sizes for the primary outcomes including the Chidren's Depression Rating Scale - Revised (CDRS-R) and Actical (energy expenditure data) as well as selected secondary outcomes; (e.g., Clinical Global Improvement, depression rating scales, exercise logs, attitudes), and 2) determining whether moderate to strenuous exercise (12 kcal/kg/week [KKW]) versus a control stretching activity (<4 KKW) for 12 weeks leads to a clinically meaningful reduction in depressive symptoms and/or improved psychosocial functioning. The challenge is to develop an exercise intervention that can motivate a typically sedentary depressed adolescent to exercise on a regular basis. The goal is to demonstrate that exercise alone can provide an important and effective non-medication intervention for adolescent depression. This paper reports on the rationale and design of a pilot study which aims to inform the design of a larger trial to evaluate the efficacy of aerobic exercise to treat adolescent depression. After describing the case for exercise within the broader context of the prevalence of adolescent depression and other treatments, the paper describes the intervention and procedures for data collection.

Exercise in the treatment of depression

A large body of research supports the use of exercise as a treatment for depression across a wide range of ages and with special populations, such as pregnant women and women who suffer from postpartum depression. However, methodologic limitations have historically limited our ability to interpret and understand previous research findings, which in turn may have hindered acceptance of exercise as treatment for depressed patients. This review provides information on some of the most salient studies of exercise as a treatment for depression and highlights important methodologic issues that have limited this area of research. In addition, several ongoing studies that were designed to address these limitations are reviewed. These and future well-designed trials can better inform the field regarding the utility of exercise in the treatment of depression.

Strategies to enhance the therapeutic efficacy of antidepressants: targeting residual symptoms

Major depressive disorder (MDD) is an illness of great morbidity that affects many people across the world. The current goal for treatment of MDD is to achieve remission (i.e., no depressive symptoms). However, despite scientific advances in the treatment for MDD, antidepressants as first-line agents yield only modest remission rates. In fact, a recent study indicated that only one out of three subjects who received a standard, first-line antidepressant attained remission. Not achieving remission from depressive symptoms increases the risk of a more chronic and debilitating course of illness with frequent recurrences. Although a number of reasons contribute to these modest outcomes, the presence of residual symptoms is a major problem. Residual symptoms are defined as symptoms that linger despite an adequate dose and duration of an antidepressant medication. This article reviews the prevalence and clinical impact of common residual symptoms and discusses the utility of aggressively addressing residual symptoms to enhance the efficacy of antidepressant medications.

Exercise as an augmentation strategy for treatment of major depression

The use of augmentation strategies among patients with major depression is increasing because rates of complete remission with standard antidepressant monotherapy are quite low. Clinical and neurobiological data suggest that exercise may be a good candidate for use as an augmentation treatment for depression. This pilot study examined the use of exercise to augment antidepressant medication in patients with major depression. Seventeen patients with incomplete remission of depressive symptoms began a 12-week exercise program while continuing their antidepressant medication (unchanged in type or dose). Individual exercise prescriptions were calculated based on an exercise dose consistent with currently recommended public health guidelines. The exercise consisted of both supervised and home-based sessions. The 17-item Hamilton Rating Scale for Depression (HRSD17) and the Inventory of Depressive Symptomatology-Self-Report (IDS-SR30) were used to assess symptoms of depression on a weekly basis. Intent-to-treat analyses yielded significant decreases on both the HRSD17 (5.8 points, p < 0.008) and IDS-SR30 (13.9 points, p < 0.002). For patients who completed the study (n = 8), HRSD17 scores decreased by 10.4 points and IDS-SR30 scores decreased by 18.8 points. This study provides preliminary evidence for exercise as an effective augmentation treatment for antidepressant medication. This is a lower-cost augmentation strategy that has numerous health benefits and may further reduce depressive symptoms in partial responders to antidepressant treatment. Practical tips on how practitioners can use exercise to enhance antidepressant treatment are discussed. Longer-term use of exercise is also likely to confer additional health benefits for this population.

Impaired delay and trace eyeblink conditioning performance in major depressive disorder

BACKGROUND

Preliminary evidence obtained in our lab has revealed that depressive symptoms impair associative learning, as measured by acquisition of eyeblink classical conditioning (EBCC) tasks. The current study assesses EBCC acquisition in individuals with major depressive disorder (MDD).

METHODS

The 17-item Hamilton Rating Scale for Depression (HAM-D(17)) and the 30-item Inventory for Depressive Symptomatology, Self-Report (IDS-SR(30)) were used to quantify severity of depressive symptoms. Participants received 60 trials each in delay 500, trace 500, and trace 1000 conditioning paradigms. A 150-ms, 5-7 psi air puff served as the unconditioned stimulus (US), and an 80-dB, 1-kHz tone as the conditioned stimulus (CS). Mean percent conditioned responses (CRs) served as the primary measure of task acquisition.

RESULTS

The MDD group generated significantly fewer CRs on delay 500 and trace 500 tasks, and approached significance on the trace 1000 task compared to healthy controls. Furthermore, presentation of successive trials did not increase CR production in the depressed group, in contrast to progressive increases observed in the control group.

LIMITATIONS

The presentation of multiple EBCC tasks precludes some detailed analyses of task-specific performance. Future studies may also benefit from including sufficient numbers of subjects to assess differential characteristics of depression (e.g., length of episode, depressive subtype) and treatment effects.

CONCLUSIONS

These data suggest that MDD impairs acquisition of EBCC, providing behavioral support for cerebellar and hippocampal dysfunction in depression. Delineating the neural substrates involved in MDD may aid in future treatment approaches for this pervasive disorder.

Reductions in Stress and Depressive Symptoms in Mothers of Substance-Exposed Infants, Participating in a Psychosocial Program

OBJECTIVE

Depression profoundly impairs psychosocial functioning. Depression can have disruptive effects on a person's family, with significant impact on the psychosocial development of the children. Recent research suggests that a mother's depressive symptoms may increase parenting stress and that parenting stress may, in turn, increase depressive symptoms, with a possible negative cycle to this process. Little is known about how these two factors interact in drug-involved mothers. This study examines how the NEW CONNECTIONS intervention (a parental education and support program for drug-involved parents) acts on parental stress and symptoms of depression.

METHODS

The study site was the NEW CONNECTIONS Infant Intervention Program. The Beck Depression Inventory-II (BDI-II) and the Parenting Stress Index (PSI) were administered to drug- and alcohol-involved mothers (N = 120) at baseline and after the intervention (Week 12).

RESULTS

Four of the seven PSI domains of parenting stress showed a significant reduction (Demandingness, Competence, Isolation, and Role Restriction). Changes in four domains were significantly correlated with reductions in depressive symptoms (Competence, Isolation, Attachment, and Role Restriction). There was a significant reduction in depressive symptoms as measured by the BDI-II.

CONCLUSION

Reduction in some aspects of parenting stress is associated with reduction in depressive symptoms in mothers of substance-exposed infants who participated in the NEW CONNECTIONS psychosocial intervention targeting the parent-child relationship.

Thyrotropin-releasing hormone-receptor interaction in GH3 pituitary cells

The interaction between TRH and GH3 pituitary tumor cells was studied in monolayer cultures or membrane-containing fractions. In intact cells, the apparent dissociation constant (Kd) was approximately 10 nM, and the total number of binding sites was approximately 1.4 pmol/mg protein at temperatures of 0-37 C. In broken cell preparations, the number of sites occupied at saturating TRH concentrations was reduced by half when the temperature was increased from 0 to 30 C. Linear Scatchard plots were obtained under all conditions. The rate of dissociation of TRH was temperature dependent, and first order plots were nonlinear. The half-times for dissociation at 0 C were over 240 min in cells and membranes, while at 37 C, the half-time values were 24 min (cells) and less than 0.5 min (membranes). Identical dissociation kinetics were obtained by dilution alone or dilution with excess unlabeled hormone. When cultures which had been incubated with TRH were lightly fixed with glutaraldehyde, dissociation at 37 C became immeasurably slow. However, TRH dissociated immediately when sodium dodecyl sulfate, ethanol, or acetone was added, indicating that the tripeptide was not covalently coupled to cell proteins. The data indicate that binding of TRH to high affinity GH3 receptors is not cooperative, and that the majority of TRH bound after short incubations is dissociable.

Relationships between thyroid hormone and glucocorticoid effects in GH3 pituitary cells

The interrelationships between thyroid hormone and cortisol actions were investigated in GH3 pituitary tumor cells. When GH3 cells were grown in thyroid hormone-deficient medium, cortisol did not affect the concentration of TRH receptors. Both thyroid hormones and TRH normally decrease the number of TRH receptors, and cortisol inhibited down-regulation by both hormones. TRH caused a greater increase in PRL synthesis when TRH receptors were high in the presence of cortisol and T3 than when TRH receptors were low (T3 alone). In the presence of cortisol, higher concentrations of T3 were required to decrease TRH receptors, while lower concentrations were necessary to stimulate GH synthesis. Cortisol and T3 alone stimulated GH synthesis 6- and 10-fold, respectively, while together they caused an 830-fold increase. In contrast, T3 did not alter the inhibition of PRL synthesis by the glucocorticoid. Cortisol did not significantly affect the amount of [125I]T3 bound to nuclei from cells incubated in thyroid hormone-deficient or T3-supplemented medium (approximately 100 and approximately 25 fmol/mg cell protein). The data suggest that cortisol modifies thyroid hormone action at a step subsequent to T3 receptor binding.