Biomedical subjects

Heather O Chambliss

Publications and source records attributed to Heather O Chambliss.

8 recordsLinked to original sources

PubMed2006

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.

Adult↗

PubMed2006

TREAD: TReatment with Exercise Augmentation for Depression: study rationale and design.

BACKGROUND: Despite recent advancements in the pharmacological treatment of major depressive disorder (MDD), over half of patients who receive treatment with antidepressant medication do not achieve full remission of symptoms. There is evidence that exercise can reduce depressive symptomatology when used as a treatment for MDD. However, no randomized controlled trials have evaluated exercise as an augmentation strategy for patients with carefully diagnosed MDD who remain symptomatic following an adequate acute phase trial of antidepressant therapy. PURPOSE: TReatment with Exercise Augmentation for Depression (TREAD) is an NIMH-funded, randomized, controlled trial designed to assess the relative efficacy of two doses of aerobic exercise to augment selective serotonin reuptake inhibitor (SSRI) treatment of MDD. METHODS: The TREAD study includes 12 weeks of acute phase treatment with a 12-week post-treatment follow-up. In addition to looking at change in depressive symptoms as a primary outcome, it also includes comprehensive assessment of psychosocial function and treatment adherence. RESULTS: This paper reviews the rationale and design of TREAD and illustrates how we address several key issues in contemporary patient-oriented research on MDD: 1) the use of augmentation strategies in the treatment of depressive disorders in general, 2) the use of non-pharmacological strategies in the treatment of depressive disorders, 3) the considerations of designing a well-controlled trial using two active treatment groups, and 4) the implementation of an adherence program for the use of exercise as a treatment strategy. CONCLUSIONS: The TREAD study is uniquely designed to overcome sources of potential bias and threats to internal and external validity that have limited prior research on the mental health effects of exercise. The study is facilitated by the development of a multidisciplinary research team that includes experts in both depression treatment and exercise physiology, as well as other related fields.

Adolescent↗

PubMed2005

Exercise treatment for depression: efficacy and dose response.

BACKGROUND: This study, conducted between 1998 and 2001 and analyzed in 2002 and 2003, was designed to test (1) whether exercise is an efficacious treatment for mild to moderate major depressive disorder (MDD), and (2) the dose-response relation of exercise and reduction in depressive symptoms. DESIGN: The study was a randomized 2x2 factorial design, plus placebo control. SETTING/PARTICIPANTS: All exercise was performed in a supervised laboratory setting with adults (n =80) aged 20 to 45 years diagnosed with mild to moderate MDD. INTERVENTION: Participants were randomized to one of four aerobic exercise treatment groups that varied total energy expenditure (7.0 kcal/kg/week or 17.5 kcal/kg/week) and frequency (3 days/week or 5 days/week) or to exercise placebo control (3 days/week flexibility exercise). The 17.5-kcal/kg/week dose is consistent with public health recommendations for physical activity and was termed "public health dose" (PHD). The 7.0-kcal/kg/week dose was termed "low dose" (LD). MAIN OUTCOME MEASURES: The primary outcome was the score on the 17-item Hamilton Rating Scale for Depression (HRSD(17)). RESULTS: The main effect of energy expenditure in reducing HRSD(17) scores at 12 weeks was significant. Adjusted mean HRSD(17) scores at 12 weeks were reduced 47% from baseline for PHD, compared with 30% for LD and 29% for control. There was no main effect of exercise frequency at 12 weeks. CONCLUSIONS: Aerobic exercise at a dose consistent with public health recommendations is an effective treatment for MDD of mild to moderate severity. A lower dose is comparable to placebo effect.

Adult↗

PubMed2005

Exercise duration and intensity in a weight-loss program.

OBJECTIVE: To examine the effect of duration and frequency of exercise on weight loss and cardiorespiratory fitness in previously sedentary, overweight, women. DESIGN: Randomized, controlled, 4-arm trial of 12-months duration. SETTING: A university-based behavioral weight loss program during the years 2000 and 2001. PARTICIPANTS: Eligibility criteria were: women, 21 to 45 years of age, body mass index (BMI) 27 to 40, reporting exercise <3 days/week for <20 minutes/day during the previous 6 months. Exclusion criteria were: a history of myocardial infarction, taking medication that would alter the heart rate response during exercise or that would affect metabolism or weight loss, being treated for psychologic conditions, pregnant, recently pregnant, or planning pregnancy, having a medical condition that could affect metabolism or body weight (eg, diabetes) or that would limit exercise participation. INTERVENTION: All 201 participants were assigned to a standard behavioral weight loss program, which included regular group meetings and telephone calls, and caloric and dietary fat restrictions. Participants were given meal plans and kept weekly food diaries. The women were assigned to 1 of 4 exercise groups based on energy expenditure of 1000 kcal/wk or 2000 kcal/wk and exercise intensity (moderate versus vigorous). Exercise intensity was prescribed according to percentage of age-predicted maximal heart rate and rating of perceived exertion. Energy expenditure was converted to minutes of exercise per week. The groups were vigorous intensity/high duration, moderate intensity/high duration, moderate intensity/moderate duration, and vigorous intensity/moderate duration. All 4 groups started the program at moderate intensity and moderate duration (100 min/week of walking) and increased the vigor and duration of exercise to set targets of 200, 300, 200, and 150 min/week, for the groups respectively. Treadmills were provided to the participants, and feedback on their weekly exercise logs was given. MAIN OUTCOME MEASURES: At 6 and 12 months, changes in body weight and BMI were measured. Cardiorespiratory fitness was measured by a graded exercise treadmill test and expressed as percent change in oxygen consumption from baseline. Excluding 5 women who left the study (because of pregnancy or death) the data were analyzed by the intention-to-treat method (completion rate 184/196 = 94%). MAIN RESULTS: Attendance at group sessions and reported dietary intake and exercise adherence suggested that all groups complied similarly with their dietary and exercise prescriptions. Mean weight loss after 1 year was 8.9, 8.2, 6.3, and 7.0 kg, for the vigorous intensity/high duration, moderate intensity/high duration, moderate intensity/moderate duration, and vigorous intensity/moderate duration groups, respectively, but there was no effect of exercise duration or exercise intensity on changes in body weight or in BMI. Cardiorespiratory fitness increased for all groups; 22%, 14.9%, 13.5%, and 18.9%, for the vigorous intensity/high duration, moderate intensity/high duration, moderate intensity/moderate duration, and vigorous intensity/moderate duration groups, respectively, but the groups did not differ in effect of exercise intensity (P = 0.11) or exercise duration (P = 0.35). When participants were divided by their reported average weekly duration of exercise at months 6 and 12, the group which averaged > or =200 min/week at both time points lost more weight than the groups which averaged <150 min/week of physical activity or whose activity duration was inconsistent (difference among groups, P = 0.01). They also had a greater percent increase in cardiorespiratory fitness than those who averaged <150 min/week of physical activity (P = 0.007) and those whose activity was inconsistent (P = 0.003). CONCLUSION: Sedentary overweight women lost weight and improved cardiorespiratory fitness in a year-long combined dietary and exercise regimen. Duration of exercise (at least 150 min/week of walking) was more important than vigorous versus moderate intensity in achieving these goals.

Comment↗

PubMed2004

Effects of chronic activity wheel running and imipramine on masculine copulatory behavior after olfactory bulbectomy.

We examined the effects of chronic activity wheel running and imipramine administration on appetitive behavior after olfactory bulbectomy (OBX). Male Long-Evans rats were randomly assigned to the following conditions using a 2 x 2 x 2 design: (1) bilateral OBX or sham surgery, (2) voluntary activity wheel running or sedentary home cage, and (3) daily imipramine or saline injections. After 21 days of treatment, animals underwent behavioral testing for copulatory activity and sucrose preference. Bulbectomized animals exhibited decrements in copulatory performance and reductions in sucrose intake compared to sham animals. Within the bulbectomized groups, imipramine-treated rats either did not copulate or had reduced ejaculation frequencies. However, activity wheel running attenuated the copulatory deficits induced by OBX. The findings encourage studies of physical activity and male sexual dysfunction among depressed men being treated by pharmacotherapy.

Animals↗

PubMed2004

Attitudes toward obese individuals among exercise science students.

PURPOSE: The purpose of this research was to evaluate attitudes toward obese individuals and to identify personal characteristics associated with antifat bias among students majoring in exercise science. METHODS: Undergraduate (N = 136) and graduate (N = 110) students (mean age 23.2 yr, 55% male, 77% Caucasian) completed a series of questionnaires to assess attitudes toward obese individuals. Instruments included the Implicit Association Test (IAT), a timed self-report assessment that measures automatic attitudes and stereotypes toward obese persons through word categorizations (good vs bad; motivated vs lazy), and the Antifat Attitudes Test (AFAT), a self-report instrument that measures negative beliefs and attitudes toward obese individuals. Participants also completed a general demographic questionnaire. RESULTS: A strong bias was found for implicit measures including good versus bad attitude (P < 0.0001) and motivated versus lazy stereotype (P < 0.0001). Characteristics associated with greater bad bias included being female, Caucasian, and growing up in a less populated area (P < 0.05). Belief in greater personal responsibility for obesity was associated with stronger lazy bias (P < 0.01). On the AFAT self-report measure, belief in less personal responsibility for obesity, positive family history of obesity, and having an obese friend were associated with lower antifat scores (P < 0.05). CONCLUSION: These results suggest that students in the field of exercise science possess negative associations and bias toward obese individuals. These findings have important implications for health promotion, as antifat bias and weight discrimination among exercise professionals may further contribute to unhealthy lifestyle behaviors and reduced quality of life for many obese individuals who are at high risk for chronic disease.

Adult↗

PubMed2003

Effects of chronic exercise and imipramine on mRNA for BDNF after olfactory bulbectomy in rat.

We examined the effects of chronic activity wheel running and antidepressant treatment on brain-derived neurotrophic factor (BDNF) messenger RNA (mRNA) in multiple brain regions-hippocampal formation (HF), ventral tegmental area/substantia nigra (VTA/SN), nucleus accumbens (NAc), and piriform cortex (PFx)-after bilateral olfactory bulbectomy (OBX). Male, Long-Evans rats (n=72) underwent either sham or OBX surgery and were randomly divided into eight experimental groups in a 2 (sham vs. OBX) x 2 (sedentary vs. activity wheel)x2 (saline vs. imipramine) factorial design. Animals were killed after 21 days of treatment. Drug x exercise interaction effects were observed for HF (P=0.006-0.023) and VTA/SN (P=0.021); exercise increased BDNF mRNA in the saline treated animals but not in the imipramine treated animals. OBX did not affect BDNF mRNA in the HF or VTA/SN (P>0.05). BDNF mRNA levels in the PFx were not altered by exercise, drug, or OBX (P>0.05). These results suggest that the effect of exercise on BDNF mRNA extends beyond the HF to the mesolimbic ventral tegmental area and that the potentiation of BDNF mRNA by exercise and antidepressant pharmacotherapy, reported by other investigators, is time limited.

Animals↗

PubMed2002

The DOSE study: a clinical trial to examine efficacy and dose response of exercise as treatment for depression.

The Depression Outcomes Study of Exercise (DOSE) was a randomized clinical trial to determine whether exercise is an efficacious treatment for mild to moderate major depressive disorder (MDD) in adults ages 20 to 45 years. The specific hypotheses under investigation were (1) active exercise is an efficacious monotherapy for mild to moderate levels of MDD, and (2) there is a dose-response relation between the exercise amount and reduction in depressive symptoms. The primary outcome measure was the Hamilton Rating Scale for Depression (HRSD) collected weekly over 12 weeks. Secondary outcome measures were the Inventory of Depressive Symptoms (clinician and self-report), HRSD scores at 24 weeks, cardiorespiratory fitness, self-efficacy, and quality of life. Eighty men and women who were diagnosed with a Structured Clinical Interview for Depression and who had mild (HRSD 12-16) to moderate (HRSD 17-25) MDD were randomized to one of five doses of exercise: 7.0 kcal/kg/week in 3 days/week; 7.0 kcal/kg/week in 5 days/week; 17.5 kcal/kg/week in 3 days/week; 17.5 kcal/kg/week in 5 days/week; or 3 days/week of stretching and flexibility exercises for 15 to 20 min/session. Participants exercised under supervision in our laboratory over the course of 12 weeks. Symptoms of depression were measured weekly by trained clinical raters blinded to the participant's treatment assignment. The design of the study restricted participant characteristics to mild to moderate MDD and controlled exercise features to permit the evaluation of exercise as a sole treatment for depression. This study is the first to examine dose-response effects of exercise in participants diagnosed with MDD.

Adult↗