RCT of a psychological intervention for patients with cancer: I. mechanisms of change

Little is known about the therapeutic processes contributing to efficacy of psychological interventions for patients with cancer. Data from a randomized clinical trial yielding robust biobehavioral and health effects (B. L. Andersen et al., 2004, 2007) were used to examine associations between process variables, treatment utilization, and outcomes. Novel findings emerged. Patients were highly satisfied with the treatment, but their higher levels of felt support (group cohesion) covaried with lower distress and fewer symptoms. Also, specific treatment strategies were associated with specific outcomes, including lower distress, improved dietary habits, reduced symptomatology, and higher chemotherapy dose intensity. These data provide a comprehensive test of multiple therapeutic processes and mechanisms for biobehavioral change with an intervention including both intensive and maintenance phases.

Meaning in life mediates the relationship between social and physical functioning and distress in cancer survivors

OBJECTIVES

Impairments in physical and social functioning are often associated with distress for the cancer survivor. Impaired functioning may also lead individuals to question previously held beliefs about meaning in life. Meaning in life was hypothesized to mediate the relationship between functioning and distress.

DESIGN AND METHODS

Two studies were conducted. In the cross-sectional study (I), cancer survivors (N=420) were accrued via the Internet and completed measures of social and physical functioning, meaning and distress. In the longitudinal study (II), breast cancer survivors (N=167) completed measures of functioning at 18 months, meaning at 24 months and distress at 30 months post-diagnosis.

RESULTS

In Study I, meaning in life was a significant, partial mediator for both of the effects of physical and social functioning impairments on heightened distress. In Study II, significant indirect effects of functioning impairments on distress through meaning were replicated even when functioning and distress were measured 1 year apart. The relationship of social functioning and distress was fully mediated by meaning in life, whereas the relationship of physical functioning and distress was partially mediated by meaning.

CONCLUSIONS

The negative social and physical sequelae of cancer are associated with heightened distress, and this association appears to be accounted for, in part, by patients' loss of meaning in their lives.

Distress reduction from a psychological intervention contributes to improved health for cancer patients

PURPOSE

Psychological interventions are efficacious in reducing emotional distress for cancer patients. However, it is not clear whether psychological improvements are, in turn, related to improved health. A clinical trial tests whether a psychological intervention for cancer patients can do so, and also tests two routes to achieve better health: (a) reducing patients' Emotional Distress, and/or (b) enhancing their functional immunity.

METHODS

Post-surgery, 227 breast cancer patients were randomized to intervention or assessment only Study Arms. Conducted in small groups, intervention sessions were offered weekly for 4 months and followed by monthly sessions for 8 months. Measures included psychological (distress), biological (immune), and health outcomes (performance status and evaluations of patient's symptomatology, including toxicity from cancer treatment, lab values) collected at baseline, 4 months, and 12 months.

RESULTS

A path model revealed that intervention participation directly improved health (p<.05) at 12 months. These effects remained when statistically controlling for baseline levels of distress, immunity, and health as well as sociodemographic, disease, and cancer treatment variables. Regarding the mechanisms for achieving better health, support was found for an indirect effect of distress reduction. That is, by specifically lowering intervention patients' distress at 4 months, their health was improved at 12 months (p<.05). Although the intervention simultaneously improved patients' T-cell blastogenesis in response to phytohemagglutinin (PHA), the latter increases were unrelated to improved health.

CONCLUSION

A convergence of biobehavioral effects and health improvements were observed. Behavioral change, rather than immunity change, was influential in achieving lower levels of symptomatology and higher functional status. Distress reduction is highlighted as an important mechanism by which health can be improved.

Sexual well-being among partnered women with breast cancer recurrence

PURPOSE

A woman's risk for sexual disruption after breast cancer recurrence has received little clinical or research attention.

PATIENTS AND METHODS

Breast cancer patients recently diagnosed with recurrence (n = 60) were initially assessed at baseline and completed follow-ups at 4, 8, and 12 months. They were compared by age, stage, and duration and frequency of follow-up with matched patients who remained disease free (n = 120). Using linear mixed modeling, the groups were compared in their trajectories of change on measures of sexuality, relationship satisfaction, cancer-specific stress, and physical functioning. Recurrence subgroups, those with locoregional versus distant disease and those younger versus older than 52 years, were also compared.

RESULTS

At baseline, the recurrence group had significantly lower intercourse frequency and physical functioning compared with the disease-free group and these differences were maintained. There were no significant differences in the frequencies of kissing or sexual and relationship satisfactions. For the recurrence group patients, the heightened stress of the diagnostic/early recurrence treatment period declined to the lower disease-free levels by 12 months. This effect was largely due to improvement of the patients with distant disease. Finally, sexual changes were most notable for younger patients.

CONCLUSION

To our knowledge, this is the first longitudinal, controlled study of sexuality-sexuality in the context of other quality of life domains-for women coping with recurrence. Despite disruption, patients maintained their sexual lives. Younger and distant recurrence patients, however, may have greatest risk of sexual disruption. The factors contributing to sexual disruption remain unknown, and studies investigating strategies to help patients maintain this aspect of quality of life are needed.

Strategies used in coping with a cancer diagnosis predict meaning in life for survivors

The search for meaning in life is part of the human experience. A negative life event may threaten perceptions about meaning in life, such as the benevolence of the world and one's sense of harmony and peace. The authors examined the longitudinal relationship between women's coping with a diagnosis of breast cancer and their self-reported meaning in life 2 years later. Multiple regression analyses revealed that positive strategies for coping predicted significant variance in the sense of meaning in life--feelings of inner peace, satisfaction with one's current life and the future, and spirituality and faith--and the absence of such strategies predicted reports of loss of meaning and confusion (ps < .01). The importance and process of finding meaning in the context of a life stressor are discussed.

Impaired natural killer cell lysis in breast cancer patients with high levels of psychological stress is associated with altered expression of killer immunoglobin-like receptors

BACKGROUND

We previously reported that cancer-related psychological stress is associated with reduced natural killer (NK) cell lysis. We hypothesized that reduced NK cell cytotoxicity in patients with increased levels of stress would correlate with alterations in the expression of inhibitory NK cell receptors (killer immunoglobulin-like receptors, or KIRs). The specific aim of this study was to examine KIR expression in patients with high or low levels of psychologic stress and correlate alterations in KIR expression with NK cell function.

MATERIALS AND METHODS

Two hundred twenty-seven patients underwent baseline evaluation of cancer-related psychological stress and were randomized to psychosocial intervention versus observation. From this population, two groups were defined based on pretreatment measurements of NK lytic activity, stress levels, and the availability of cryopreserved peripheral blood mononuclear cells (PBMC). Group I (n=9) had low stress by the Impact of Events Scale (IES), and high NK cell lysis at the 50:1 effector: target ratio (NK(50)=52-89%). Group II (n=8) had high stress and low NK(50) (27-52%). Lymphokine activated killer (LAK) activity, antibody dependent cellular cytotoxicity (ADCC), and expression of cytokine receptors, adhesion molecules, and killer immunoglobulin-like receptors (KIRs) were assessed in PBMC.

RESULTS

Incubation of PBMC with NK-stimulatory cytokines (IL-2, IL-12, or IL-15) led to significant increases in cytotoxic activity regardless of IES/NK(50) scores. There were no significant group differences in NK cell surface expression of the IL-2 receptor components CD25 and CD122, antibody-dependent lysis of HER2/neu-positive SKBr3 cells treated with an anti-HER2/neu monoclonal antibody, expression of adhesion molecules (CD2, CD11a, CD18) and markers of activation (CD69), or expression of the KIRs CD158a, NKG2a, NKB1, and CD161. However, levels of CD158b were significantly higher in Group I after incubation in media alone or with IL-2, and CD94 expression was significantly lower in Group I after incubation with IL-2.

CONCLUSIONS

In this study of a small subset of breast cancer patients chosen from a previous clinical trial of psychosocial intervention for breast cancer, impaired NK lysis in breast cancer patients with high levels of psychological stress was associated with alterations in surface expression of killer immunoglobulin-like receptors. However, immune effectors retained the ability to lyse antibody-coated targets and to initiate lymphokine-activated killer activity, irrespective of stress levels or baseline NK(50).

Individual trajectories in stress covary with immunity during recovery from cancer diagnosis and treatments

Research connects stressful events with altered immune regulation, but the role of subjective stress is uncertain. Using a longitudinal design, we provide a statistically powerful test of the relationship between subjective stress (perceived stress, emotional distress) and immunity (T cell blastogenesis, natural killer cell cytotoxicity, [NKCC]) as individuals adjust to a severe stressor, a cancer diagnosis and its treatments. Women with regional breast cancer (N=113) were assessed at diagnosis/surgery and reassessed 4, 8, 12, and 18 months later. Latent growth curve analysis tested two hypotheses: (1) initial levels of subjective stress will correlate inversely with initial levels of immunity, and (2) rate of change in subjective stress will correlate inversely with rate of change in immunity. As predicted by Hypothesis 1, participants with high initial subjective stress showed poor initial blastogenesis. As predicted by Hypothesis 2, participants exhibiting an early, rapid decline in subjective stress also showed rapid improvement in NKCC. Follow-up analyses revealed perceived stress to be strongly related to immune function, while emotional distress was not. This is the first study to investigate trajectories in stress and immunity during recovery from a major stressor. Results imply that NK and T cells are sensitive to different aspects of the stress response. While T cell blastogenesis correlated with initial (peak) subjective stress, NKCC correlated with change (improvement) in subjective stress. These data highlight the importance of subjective stress, particularly stress appraisals, in the immune response to a major stressor.

Body change stress for women with breast cancer: the Breast-Impact of Treatment Scale

BACKGROUND

Body change stress refers to subjective psychological stress that accompanies women's negative and distressing thoughts, emotions, and behaviors resultant from breast cancer and breast surgeries. Body change stress is manifest with traumatic stress-like symptoms.

PURPOSE

The development of the Breast-Impact of Treatment Scale (BITS) is described. The construct is assessed with 13 items that comprise a one-factor solution.

METHODS AND RESULTS

Tests of convergent validity demonstrate the relationship, but not overlap, of the BITS with measures of stress, emotional distress, and sexuality. The BITS distinguishes between women receiving segmental mastectomy (lumpectomy) versus mastectomy. Incremental validity is shown with comparison to ratings of body satisfaction.

CONCLUSIONS

An early psychometric foundation enables use of the BITS to assess a common and distressing quality of life outcome for women with breast cancer.

Measuring meaning in life following cancer

Meaning in life is a multi-faceted construct that has been conceptualized in diverse ways. It refers broadly to the value and purpose of life, important life goals, and for some, spirituality. We developed a measure of meaning in life derived from this conceptualization and designed to be a synthesis of relevant theoretical and empirical traditions. Two samples, all cancer patients, provided data for scale development and psychometric study. From exploratory and confirmatory factor analyses the Meaning in Life Scale (MiLS) emerged, and includes four aspects: Harmony and Peace, Life Perspective, Purpose and Goals, Confusion and Lessened Meaning, and Benefits of Spirituality. Supporting data for reliability (internal consistency, test-retest) and construct validity (convergent, discriminant, individual differences) are provided. The MiLS offers a theoretically based and psychometrically sound assessment of meaning in life suitable for use with cancer patients.

Psychological responses to cancer recurrence

BACKGROUND

There is a dearth of knowledge regarding the psychological responses to a diagnosis of cancer recurrence.

METHODS

An ongoing randomized clinical trial provided the context for prospective study. Women with Stage II/III breast carcinoma (N = 227) were initially assessed after their diagnosis/surgery and before adjuvant therapy and then reassessed every 6 months. Eight years into the trial, 30 patients had recurred (R) and were assessed shortly after receiving their second diagnosis. Their data were compared with a sample of trial patients who had no evidence of disease (disease free [DF]; n = 90). The groups were matched on study arm, disease stage, estrogen receptor status, menopausal status, and time since initial diagnosis.

RESULTS

As hypothesized, patients' cancer-specific stress at recurrence in the R group was higher (P < 0.05) than stress levels for the DF group at the equivalent point in time. Importantly, the R group reported stress for their recurrent diagnosis equivalent to that reported for their initial diagnosis. Identical results were found for measures of health status and symptomatology. In contrast, analyses for emotional distress and social functioning showed no pattern of disruption for the R group at cancer recurrence and levels equivalent to that of the DF group.

CONCLUSIONS

To the authors' knowledge, this was the first controlled, prospective psychological analysis of patients' responses to cancer recurrence. The findings were consistent with a learning theory conceptualization of the cancer stressor. Patients' stress was "compartmentalized" and did not, at least in the early weeks, result in diffuse emotional distress and quality of life disruption, underscoring the resilience of patients when confronted with cancer recurrence.

TNF-alpha levels in cancer patients relate to social variables

Tumor necrosis factor-alpha (TNF-alpha) is an important cytokine associated with tumor regression and increased survival time for cancer patients. Research evidence relates immune factors (e.g., natural killer (NK) cell counts, NK cell lysis, lymphocyte profile, and lymphocyte proliferation) to the frequency and quality of social relations among cancer patients. We hypothesized that disruptions in social relations would be associated with lower TNF-alpha responses, and conversely, that reports of positive changes in social relations correlate with stronger responses. A prospective design measured changes in social activity and relationship satisfaction with a partner in 44 breast cancer patients at the time of cancer diagnosis, and initial surgery and 12 months later. Results indicated that patients reporting increased social activities or satisfaction exhibited stronger stimulated TNF-alpha responses. This is the first study to link changes in patient social relations with a cancer-relevant immune variable.

Traumatic stress, perceived global stress, and life events: prospectively predicting quality of life in breast cancer patients

The authors investigated the relationship between stress at initial cancer diagnosis and treatment and subsequent quality of life (QoL). Women (n = 112) randomized to the assessment-only arm of a clinical trial were initially assessed after breast cancer diagnosis and surgery and then reassessed at 4 months (during adjuvant treatment) and 12 months (postadjuvant treatment). There were 3 types of stress measured: number of stressful life events (K. A. Matthews et al., 1997), cancer-related traumatic stress symptoms (M. J. Horowitz, N. Wilner, & W. Alvarez, 1979), and perceived global stress (S. Cohen, T. Kamarck, & R. Mermelstein, 1983). Using hierarchical multiple regressions, the authors found that stress predicted both psychological and physical QoL (J. E. Ware, K. K. Snow, & M. Kosinski, 2000) at the follow-ups (all ps < .03). These findings substantiate the relationship between initial stress and later QoL and underscore the need for timely psychological intervention.

Mismatch of posttraumatic stress disorder (PTSD) symptoms and DSM-IV symptom clusters in a cancer sample: exploratory factor analysis of the PTSD Checklist-Civilian Version

The Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV; American Psychiatric Association, 1994a) conceptualization of posttraumatic stress disorder (PTSD) includes three symptom clusters: reexperiencing, avoidance/numbing, and arousal. The PTSD Checklist-Civilian Version (PCL-C) corresponds to the DSM-IV PTSD symptoms. In the current study, we conducted exploratory factor analysis (EFA) of the PCL-C with two aims: (a) to examine whether the PCL-C evidenced the three-factor solution implied by the DSM-IV symptom clusters, and (b) to identify a factor solution for the PCL-C in a cancer sample. Women (N = 148) with Stage II or III breast cancer completed the PCL-C after completion of cancer treatment. We extracted two-, three-, four-, and five-factor solutions using EFA. Our data did not support the DSM-IV PTSD symptom clusters. Instead, EFA identified a four-factor solution including reexperiencing, avoidance, numbing, and arousal factors. Four symptom items, which may be confounded with illness and cancer treatment-related symptoms, exhibited poor factor loadings. Using these symptom items in cancer samples may lead to overdiagnosis of PTSD and inflated rates of PTSD symptoms.

Assessing stress in cancer patients: a second-order factor analysis model for the Perceived Stress Scale

Using the Perceived Stress Scale (PSS), perceptions of global stress were assessed in 111 women following breast cancer surgery and at 12 and 24 months later This is the first study to factor analyze the PSS. The PSS data were factor analyzed each time using exploratory factor analysis with oblique direct quartimin rotation. Goodness-of-fit indices (root mean square error of approximation [RMSEA]), magnitude and pattern of factor loadings, and confidence interval data revealed a two-factor solution of positive versus negative stress items. The findings, replicated across time, also indicate factor stability. Hierarchical factor analyses supported a second-order factor of "perceived stress." This alternative factor model of the PSS is presented along with observations regarding the measure's use in cancer research.

Cellular immunity in breast cancer patients completing taxane treatment

PURPOSE

A field study of postchemotherapy immune functioning relative to the use of taxanes is reported. Immune responses in breast cancer patients were analyzed as a function of whether patients received taxane as part of their adjuvant chemotherapy.

EXPERIMENTAL DESIGN

Immune levels of 227 stage II/III breast cancer patients were measured immediately after surgery prior to chemotherapy and again 12 months later when all chemotherapies had been completed. T-cell blastogenesis and natural killer (NK) cell lysis levels of patients receiving taxanes (n = 55) were compared with levels of patients not receiving taxanes (n = 172).

RESULTS

Regression analyses were conducted. The administration of taxane as part of combination chemotherapy predicted increased T-cell blastogenesis and NK cell cytotoxicity after the conclusion of all chemotherapies. For the Taxane group, average phytohemagglutinin-induced blastogenesis was 37% higher and NK cell cytotoxicity was 39% higher than the values for the No-Taxane group.

CONCLUSIONS

Data from group comparisons with appropriate controls in a sizable clinical sample contravene traditional wisdom that taxanes suppress patients' immune cell functions. Problems in generalizing direct-contact laboratory models to the field of cancer treatment are highlighted.

Psychological, behavioral, and immune changes after a psychological intervention: a clinical trial

PURPOSE

This randomized clinical trial tests the hypothesis that a psychological intervention can reduce emotional distress, improve health behaviors and dose-intensity, and enhance immune responses.

PATIENTS AND METHODS

We studied 227 women who were surgically treated for regional breast cancer. Before adjuvant therapy, women completed interviews and questionnaires assessing emotional distress, social adjustment, and health behaviors. A 60-mL blood sample was drawn for immune assays. Patients were randomly assigned to either the intervention group or assessment only group. The intervention was conducted in small patient groups, with one session per week for 4 months. The sessions included strategies to reduce stress, improve mood, alter health behaviors, and maintain adherence to cancer treatment and care. Reassessment occurred after completion of the intervention.

RESULTS

As predicted, patients receiving the intervention showed significant lowering of anxiety, improvements in perceived social support, improved dietary habits, and reduction in smoking (all P <.05). Analyses of adjuvant chemotherapy dose-intensity revealed significantly more variability (ie, more dispersion in the dose-intensity values) for the assessment arm (P <.05). Immune responses for the intervention patients paralleled their psychological and behavioral improvements. T-cell proliferation in response to phytohemagglutinin and concanavalin A remained stable or increased for the Intervention patients, whereas both responses declined for Assessment patients; this effect was replicated across three concentrations for each assay (all P <.01).

CONCLUSION

These data show a convergence of significant psychological, health behavior, and biologic effects after a psychological intervention for cancer patients.

The gynecologic oncology consult: symptom presentation and concurrent symptoms of depression and anxiety

OBJECTIVE

To detail the relationship of gynecologic symptoms and sociodemographic variables to depression and anxiety reports among women who were referred to gynecologic oncologists for evaluation.

METHODS

Consecutive patients (N = 151) from an National Cancer Institute-designated comprehensive cancer center were accrued and participated on the day of consultation. Patients completed measures assessing depression (Center for Epidemiological Studies Depression Scale) and anxiety (Beck Anxiety Inventory) symptoms, common gynecologic signs/symptoms, and sociodemographic characteristics. Patients were followed up and subsequent diagnoses yielded 73 (48%) cancer and 78 (52%) benign cases.

RESULTS

Descriptive analyses revealed that the cancer group was significantly older (52 versus 45 years) than the benign group, and variables correlated with age also differed significantly, with the cancer sample more likely to be postmenopausal, unemployed, and if employed, working fewer hours per week. Importantly, the groups did not differ on reports of depressive, anxiety, or gynecologic symptoms. Hierarchical multiple regression analyses, collapsing across groups, yielded significant correlates of emotional distress. Women who were older, without a spouse/partner, and who had more gynecologic symptoms had higher levels of both depressive and anxiety symptoms. Among the women who did have a partner, those with relationships of longer duration reported lower levels of depression/anxiety

CONCLUSION

Reports of clinically significant depressive (42%) and anxiety symptoms (30%) were high. The number of gynecologic symptoms was reliably correlated with emotional distress. Age and absence of partner may have conferred added vulnerability. For those women with partners, lengthier relationships appeared to offer protection from both depressive and anxiety symptoms.

LEVEL OF EVIDENCE

III

When fit indices and residuals are incompatible

Standard chi-square-based fit indices for factor analysis and related models have a little known property: They are more sensitive to misfit when unique variances are small than when they are large. Consequently, very small correlation residuals indicating excellent fit can be accompanied by indications of bad fit by the fit indices when unique variances are small. An empirical example of this incompatibility between residuals and fit indices is provided. For illustrative purposes, an artificial example is provided that yields exactly the same correlation residuals as the empirical example but has larger unique variances. For this example, the fit indices indicate excellent fit. A theoretical explanation for this phenomenon is provided using relationships between unique variances and eigenvalues of the fitted correlation matrix.

When fit indices and residuals are incompatible

Standard chi-square-based fit indices for factor analysis and related models have a little known property: They are more sensitive to misfit when unique variances are small than when they are large. Consequently, very small correlation residuals indicating excellent fit can be accompanied by indications of bad fit by the fit indices when unique variances are small. An empirical example of this incompatibility between residuals and fit indices is provided. For illustrative purposes, an artificial example is provided that yields exactly the same correlation residuals as the empirical example but has larger unique variances. For this example, the fit indices indicate excellent fit. A theoretical explanation for this phenomenon is provided using relationships between unique variances and eigenvalues of the fitted correlation matrix.

Natural carbon isotopes used to study methane consumption and production in soil

Changes in the isotopic composition of carbon can be used to reveal simultaneous occurrence of methane production and oxidation in soil. The method is conducted in laboratory jar experiments as well as in the field by using flux chambers. Simultaneous occurrence of production and oxidation of methane was suggested.

Biobehavioral outcomes following psychological interventions for cancer patients

Psychological interventions for adult cancer patients have primarily focused on reducing stress and enhancing quality of life. However, there has been expanded focus on biobehavioral outcomes--health behaviors, compliance, biologic responses, and disease outcomes--consistent with the Biobehavioral Model of cancer stress and disease course. The author reviewed this expanded focus in quasiexperimental and experimental studies of psychological interventions, provided methodologic detail, summarized findings, and highlighted novel contributions. A final section discussed methodologic issues, research directions, and challenges for the coming decade.

Biobehavioral outcomes following psychological interventions for cancer patients

Psychological interventions for adult cancer patients have primarily focused on reducing stress and enhancing quality of life. However, there has been expanded focus on biobehavioral outcomes--health behaviors, compliance, biologic responses, and disease outcomes--consistent with the Biobehavioral Model of cancer stress and disease course. The author reviewed this expanded focus in quasiexperimental and experimental studies of psychological interventions, provided methodologic detail, summarized findings, and highlighted novel contributions. A final section discussed methodologic issues, research directions, and challenges for the coming decade.