Michael J. Mackenzie

Affect and Mindfulness as Predictors of Change in Mood Disturbance, Stress Symptoms, and Quality of Life in a Community-Based Yoga Program for Cancer Survivors

Little attention has been paid to the psychological determinants by which benefits are accrued via yoga practice in cancer-related clinical settings. Using a longitudinal multilevel modeling approach, associations between affect, mindfulness, and patient-reported mental health outcomes, including mood disturbance, stress symptoms, and health-related quality of life (HRQL), were examined in an existing seven-week yoga program for cancer survivors. Participants (N = 66) were assessed before and after the yoga program and at three- and six-month follow-ups. Decreases in mood disturbance and stress symptoms and improvements in HRQL were observed upon program completion. Improvements in mood disturbance and stress symptoms were maintained at the three- and six-month follow-ups. HRQL exhibited further improvement at the three-month follow-up, which was maintained at the six-month follow-up. Improvements in measures of well-being were predicted by initial positive yoga beliefs and concurrently assessed affective and mindfulness predictor variables. Previous yoga experience, affect, mindfulness, and HRQL were related to yoga practice maintenance over the course of the study.

Subjective memory impairment and well-being in community-dwelling older adults

The relationship between subjective memory impairment (SMI), future cognitive decline, and negative health status provides an opportunity for interventions to reduce memory complaints in high‐risk groups. This study aimed to examine the relationship between SMI and indicators of well‐being in older adults enrolled in an exercise trial. Additionally, the study examined whether two different modes of exercise training, aerobic walking and non‐aerobic flexibility, toning, and balance, differentially influenced subjective memory across the trial.

Associations between Physical Fitness Indices and Working Memory in Breast Cancer Survivors and Age-Matched Controls

BACKGROUND This study examined the effects of cardiorespiratory fitness, heart rate recovery, and physical activity on working memory in breast cancer survivors and age-matched controls. METHOD Using a case-control design, 32 women who had received a breast cancer diagnosis and completed primary treatment within the past 36-months (11 radiation only; 21 chemotherapy) and 30 age-matched women with no previous cancer diagnosis completed a n-back continuous performance task commonly used as an assessment of working memory. In addition, cardiorespiratory fitness and heart rate recovery were measured during a submaximal graded exercise test and physical activity was measured using 7-days of accelerometer monitoring. RESULTS Breast cancer survivors who had received chemotherapy had poorer heart rate recovery (p = .010) and engaged in less physical activity than women who had received radiation only (p = .004) or non-cancer controls (p = .029). Cancer treatment (radiation; chemotherapy) predicted differences in reaction times on the 1-back working memory task (p = .029). However, more rapid heart rate recovery predicted shorter reaction times on the 1-back task in the age-matched control group (p = .002). All participants with greater cardiorespiratory fitness displayed greater accuracy independent of disease status on the 1-back task (p = .017). No significant group differences in reaction times were observed for 2-back target trials between breast cancer survivors and controls. However, greater total physical activity predicted shorter reaction times in breast cancer survivors (radiation, chemotherapy) on the 2-back task (p = .014). In addition, all participants who exhibited more rapid heart rate recovery demonstrated better greater accuracy regardless of disease status (p = .013). CONCLUSION These findings support differences in physical activty participation, heart rate recovery, and 1- and 2-back working memory reaction times between breast cancer survivors and age-matched controls. Greater cardiorespiratory fitness, heart rate recovery, and physical activity were positively associated with better working memory performance across conditions.

Higher cardiorespiratory fitness levels are associated with greater hippocampal volume in breast cancer survivors.

As breast cancer treatment is associated with declines in brain and cognitive health, it is important to identify strategies to enhance the cognitive vitality of cancer survivors. In particular, the hippocampus is known to play an important role in brain and memory declines following cancer treatment. The hippocampus is also known for its plasticity and positive association with cardiorespiratory fitness (CRF). The present study explores whether CRF may hold promise for lessening declines in brain and cognitive health of a sample of breast cancer survivors within 3 years of completion of primary cancer treatment. We explored the role of cardiovascular fitness in hippocampal structure in breast cancer survivors and non-cancer female controls, as well as performed a median split to compare differences in hippocampal volume in relatively higher fit and lower fit cancer survivors and non-cancer controls. Indeed, CRF and total hippocampal volume were positively correlated in the cancer survivors. In particular, higher fit breast cancer survivors had comparable hippocampal volumes to non-cancer control participants (Cohen’s d = 0.13; p > 0.3), whereas lower fit breast cancer survivors showed significantly smaller hippocampal volumes compared to both lower fit and higher fit control participants (Cohen’s d = 0.87, p < 0.05). These results are the first to identify that CRF may protect the brain health of breast cancer survivors within 3 years of treatment. The present study uniquely contributes to the field of cancer and cognition and emphasizes the importance of investigating how individual differences in CRF play a role in brain changes of breast cancer survivors.

Moderate Physical Activity Mediates the Association between White Matter Lesion Volume and Memory Recall in Breast Cancer Survivors

Increased survival rates among breast cancer patients have drawn significant attention to consequences of both the presence of cancer, and the subsequent treatment-related impact on the brain. The incidence of breast cancer and the effects of treatment often result in alterations in the microstructure of white matter and impaired cognitive functioning. However, physical activity is proving to be a successful modifiable lifestyle factor in many studies that could prove beneficial to breast cancer survivors. This study investigates the link between white matter lesion volume, moderate physical activity, and cognition in breast cancer survivors following treatment compared to non-cancer age-matched controls. Results revealed that brain structure significantly predicted cognitive function via mediation of physical activity in breast cancer survivors. Overall, the study provided preliminary evidence suggesting moderate physical activity may help reduce the treatment related risks associated with breast cancer, including changes to WM integrity and cognitive impairment.

Effects of a Home-Based DVD-Delivered Physical Activity Program on Self-Esteem in Older Adults: Results From a Randomized Controlled Trial

Objective Although center-based supervised physical activity interventions have proved to be successful in attenuating health declines in older adults, such methods can be costly and have limited reach. In the present study, we examined the effects of a DVD-delivered exercise intervention on self-esteem and its subdomains and the extent to which these effects were maintained. In addition, we examined whether psychological, demographic, and biological factors acted as determinants of self-esteem. Methods Low-active, older adults (n = 307; mean [standard deviation] age =71.0 [5.1] years) were randomly assigned to a 6-month, home-based exercise program consisting of a DVD-delivered exercise intervention focused on increasing flexibility, toning, and balance (FlexToBa) or an attentional control DVD condition focused on healthy aging. Physical self-worth and three subdomains of self-esteem, global self-esteem, and self-efficacy were assessed at baseline, 6 months, and 12 months. Results There was a differential effect of time for the two groups for physical self-worth (F interaction(2,530.10) = 4.17, p = .016) and perception of physical condition (F interaction(1,630.77) = 8.31, p = .004). Self-efficacy, sex, body mass index, and age were significant predictors of changes in physical self-worth and perception of physical condition. Conclusion Our findings suggest that a DVD-delivered exercise intervention is efficacious for improving and maintaining subdomain and domain levels of self-esteem in older adults. In addition, self-efficacy was the strongest predictor of changes in physical self-worth and perceptions of physical condition. This innovative method of delivering an exercise training program via DVD is practical and effective and has the potential for broad reach and dissemination. Trial Registration Clinicaltrials.gov identifier: NCT01030419.

Yoga Helps Put the Pieces Back Together: A Qualitative Exploration of a Community-Based Yoga Program for Cancer Survivors

Objective. A qualitative research methods approach was used to explore the experiences of participants in an ongoing community-based yoga program developed for cancer survivors and their support persons. Methods. 25 participants took part in a series of semistructured focus groups following a seven-week yoga program and at three- and six-month follow-ups. Focus groups were transcribed verbatim and analyzed using a process of inductive thematic analysis. Results. The group was comprised of 20 cancer survivors, who were diagnosed on average 25.40 (20.85) months earlier, and five support persons. Participants had completed the yoga program an average of 3.35 (3.66) times previously and attended approximately 1.64 (0.70) of three possible focus groups. Four key themes were identified: (1) safety and shared understanding; (2) cancer-specific yoga instruction; (3) benefits of yoga participation; (4) mechanisms of yoga practice. Conclusions. Qualitative research provides unique and in-depth insight into the yoga experience. Specifically, cancer survivors and support persons participating in a community-based yoga program discussed their experiences of change over time and were acutely aware of the beneficial effects of yoga on their physical, psychological, and social well-being. Further, participants were able to articulate the mechanisms they perceived as underpinning the relationship between yoga and improved well-being as they developed their yoga practice.

Impact of Mindfulness-based Parenting on Women in Treatment for Opioid Use Disorder

Objectives: Mothers with opioid use disorder are at high risk for maladaptive parenting. The present observational study aimed to measure the impact of a trauma-informed mindfulness-based parenting (MBP) intervention on quality of parenting behaviors of mothers primarily with opioid use disorders as well as examine associations between exposure to adverse childhood experiences and self-reported mindful parenting. Methods: A pretest posttest design was used with repeated measures. A total of 160 women were recruited from a substance use treatment program into the 12-week-long group-based intervention comprised didactic and experiential mindfulness activities. The Keys to Interactive Parenting Scale (KIPS) measured quality of parenting behavior, the Adverse Childhood Experiences Tool captured history of exposure to childhood trauma, and the Interpersonal Mindfulness in Parenting (IM-P) scale measured the degree of mindful parenting. Analyses were conducted using multilevel modeling. Results: The MBP intervention resulted in clinically significant improvements in KIPS total and all subscale scores and an IM-P total score. Data showed higher baseline Adverse Childhood Experiences and higher program attendance significantly predicted improved overall quality of parenting behaviors at a greater rate over time. Higher IM-P scores were associated with greater rate of improvement in KIPS total and all subscale scores. Conclusions: Study findings suggest a trauma-informed MBP intervention for parenting women with opioid use disorders is associated with significant clinical improvements in quality of parenting behavior. Results of this model show promise in supporting parenting of mothers receiving treatment for opioid use disorders to enhance bonding and parenting.

Cognitive Impairment in Breast Cancer Survivors

An increasing population of breast cancer patients and survivors is living with treatment-related side effects including cancer-related cognitive impairment (CRCI). Neuropsychological and neuroimaging studies suggest changes in cognitive function and brain structure and function during and after treatment. CRCI has proven difficult to treat due to a lack of understanding of the precise underlying mechanisms and lack of consensus on the appropriate assessments to diagnose the presence and severity of cognitive dysfunction. Using the aging literature as a model, physical activity, cardiorespiratory fitness, and exercise training may protect against CRCI or restore declines in cognitive function. Preliminary studies with breast cancer survivors suggest physical activity interventions may improve cognitive function. Standardized objective assessments and normative values for the measurement of CRCI and physical activity-related factors are needed. The relationship between physical activity, exercise training, cardiorespiratory fitness, and CRCI needs to be further investigated to explore the potential for therapeutic improvement.