Application of appropriate use criteria for stress myocardial perfusion imaging at two academic medical centers: compliance and association with image findings.

PURPOSE: Explore the extent to which stress myocardial perfusion imaging (MPI) studies for coronary heart disease detection met published appropriate use criteria (AUC), and the association between AUC classification and image findings. DATA SOURCES: Retrospective, descriptive review of stress studies performed at the University of Washington Medical Center (UWMC n= 1377) and the Veterans Health Administration of Puget Sound (VA n= 1445) in the 31 months following AUC publication. CONCLUSIONS: At UWMC and VA, 69% and 89% of MPI studies, respectively, were classified as appropriate, 16% and 3% as inappropriate, and 15% and 8% as uncertain. All differences were significant, p < .001. At UWMC, 11% of appropriate studies and 10% of inappropriate or uncertain studies were abnormal (demonstrating myocardial ischemia or myocardial infarction), p= .93; these analyses were not performed on VA studies. IMPLICATIONS FOR PRACTICE: Most studies at both sites were classified as appropriate. At UWMC, the likelihood of a study classified as appropriate demonstrating an abnormality was not significantly different from a study classified as uncertain or inappropriate. AUC are imperfect tools but are increasingly created and referenced; as such, it is vital that practicing nurse practitioners are knowledgeable about their creation, application, and evaluation.

Glycemic control among older adult hematopoietic cell transplant recipients.

Adults age 55 and older with hematological malignancies who require hematopoietic cell transplantation (HCT) for survival are at risk for a number of nonmalignancy-related, potentially life-threatening outcomes, often due to suboptimal immune function. Evidence is emerging regarding how abnormal glycemic levels-newly termed malglycemia-impair cells of the immune system. Further, older adult HCT recipients appear highly susceptible to malglycemic states, particularly hyperglycemia, due to treatment regimens, nutritional imbalances, states of immobility, and stress, all coupled with the natural aging process. Patients with preexisting diabetes may be at further risk for malglycemic states. The growing number of older adults receiving HCT will substantially increase the likelihood nurses will have to provide care to HCT survivors. Therefore, it is important nurses in all practice settings have an understanding of the short-and long-term effects of glycemic status on immune function.

The graduate record examination: help or hindrance in nursing graduate school admissions?

Do graduate record examination (GRE) scores serve as strong predictors of student success in graduate school in nursing, and if so, is the extent to which they may indicate success outweighed by their perceived role as a barrier to application to graduate school in nursing? Academic ability, defined as cumulative grade point average (GPA), was used as the outcome indicator for success in graduate school and was compared with admission GRE scores for 217 students admitted to graduate programs at the University of Washington School of Nursing over a 1-year period. The GRE presented a large barrier to application that far outweighed the limited benefit of predicting 5% to 8% of explained variance in GPA.

Heart rate variability and 24-hour minimum heart rate.

Heart rate variability (HRV) indices based on 24-hr electrocardiograph recordings have been used in clinical research studies to assess the aggregate activity of the autonomic nervous system. Although 24-hr HRV is generally considered noninvasive, use in research protocols typically involves considerable data collection and processing expenses and substantial participant burden. The purposes of this research methods evaluation were to describe the relationships between 24-hr minimum heart rate (HR) and several 24-hr time domain HRV indices (Ln SDNN, Ln SDANN, Ln SDNNIDX, Ln RMSSD, and Logit50) across several research data sets (normal women, normal men, children enrolled in a study of recurrent abdominal pain, women with irritable bowel syndrome, sudden cardiac arrest survivors, and heart failure patients) and to explore the possibility that 24-hr minimum HR might serve as a simpler alternative or adjunct to HRV measures in some situations. The correlations of global HRV measures (e.g., Ln SDNN, Ln SDANN) with 24-hr minimum HR were consistently larger (typical r approximately -.80) than with average HR (typical r approximately -.50). In repeated measurements, change in minimum HR was also correlated with change in general HRV (typical r approximately -.60). However, modest differentiation of minimum HR and HRV measures was noted in patients taking certain classes of cardiac medications (e.g., anti-arrhythmics, beta blockers). Twenty-four-hour minimum HR is correlated with general time domain HRV measures and might be useful as a simpler proxy, surrogate, or auxiliary variable in some clinical research applications, especially those in which participants are not receiving cardiac medications.

Increased symptoms in female IBS patients with dysmenorrhea and PMS.

Women with irritable bowel syndrome often report premenstrual distress syndrome and dysmenorrhea. A descriptive, four-group comparison design was used to compare the symptoms and psychological distress levels of women with irritable bowel syndrome (age 18-45 years) with and without dysmenorrhea and premenstrual distress syndrome. Data from three studies on women with irritable bowel syndrome (n = 226) collected between 1995 and 2004 were combined. Of these, 38 had self-reported irritable bowel syndrome with dysmenorrhea and premenstrual distress syndrome, 59 had irritable bowel syndrome with premenstrual distress syndrome, 15 had irritable bowel syndrome and dysmenorrhea, and the remaining 114 had irritable bowel syndrome only. Participants completed the Symptom Checklist-90 Revised and a symptom diary. Pain symptoms and computed scales of anxiety, depression, anger, and cognitive difficulties were compared during the luteal phase, menses phase, and for the change from luteal to menses phases. Premenstrual distress syndrome and dysmenorrhea had a strong impact on uterine cramping at menses, and a weaker effect on other pain symptoms at both luteal and menses phases. Premenstrual distress syndrome was associated with higher depression, anger, and cognitive problems at both luteal and menses phases; however, it was not associated with a greater increase from luteal to menses phases for any symptoms other than uterine cramping. The multiple symptoms reported by women with both irritable bowel syndrome and premenstrual distress syndrome suggest that this group may be particularly challenging to treat and may require a multicomponent (e.g., education, diet, relaxation, cognitive restructuring) approach.

Abdominal pain impacts quality of life in women with irritable bowel syndrome.

OBJECTIVES: Patients with irritable bowel syndrome (IBS) report lower health-related quality of life (QoL) as compared to healthy controls. The aims of this analysis were to describe which IBS symptoms were rated on a daily diary as most distressing/severe by IBS women, and determine which IBS symptoms were most predictive of lower QoL and have the greatest impact on daily life. METHODS: This report is a secondary analysis of prospective and retrospective symptom severity and impact data, collected on 242 women with IBS, aged 18-48, who were studied between 1997 and 2004. RESULTS: On the daily diary, intestinal gas was the most frequent IBS symptom with subjects reporting at least minimal intestinal gas on 74% of days and moderate or worse severity on 27% of days. Abdominal pain occurred at least minimally on 62% of days. Diarrhea was the least common. Across women, abdominal pain was most strongly related to life impact variables and QoL, followed by intestinal gas and bloating. Analysis of day-to-day variation within women showed that abdominal pain was most strongly correlated with daily life impact variables and constipation had the weakest correlation. While diarrhea had a lower correlation with life impact, this was due to the low prevalence of diarrhea. When it occurs, diarrhea has a large impact. Partial correlation analysis showed that the impact of diarrhea is independent of abdominal pain. CONCLUSION: Abdominal pain is the most disruptive IBS symptom. Diarrhea also has an independent and significant impact when it occurs, especially in those with diarrhea-predominant IBS.

Stress, stress response, and health.

Components of stress and the stress response differ between men and women. The tend-and-befriend response, mediated by oxytocin and endogenous opioids, may be more applicable to women than the fight-or-flight response, which was based largely on studies of men. Even within the flight-or-flight response pattern there are sex-based differences. The HPA axis interacts with reproductive function, such as menstruation. For immune function there are sex differences as well as differences within the menstrual phase. Inclusion of men and women in stress response studies is critical. Further study is needed to clarify the influence of ovarian hormones on the stress and immune responses during the reproductive stages in women's lives, including menarche. pregnancy, and perimenopause.

Sleep-disordered breathing in patients with heart failure: pathophysiology, assessment, and management.

PURPOSE: To provide clinicians in primary care settings information on the effects of sleep-disordered breathing in patients with heart failure (HF). Assessment and screening tools, as well as management considerations, are presented. DATA SOURCES: Review of the scientific literature of the past 10 years, along with classic studies and Internet sources. CONCLUSIONS: HF is an increasingly prevalent problem with a high degree of associated sleep-disordered breathing. There are two broad categories of sleep-disordered breathing: obstructive sleep apnea and central sleep apnea/Cheyne-Stokes breathing. Both of these occur on a continuum of mild hypopnea to severe apnea with hypoxia. Sleep apneas are particularly harmful to patients with HF and, if left untreated, may adversely affect their prognosis. Yet sleep apnea is not routinely screened for in this population. IMPLICATIONS FOR PRACTICE: Given the serious consequences of untreated sleep-disordered breathing, there is sound justification to screen for sleep apnea in all patients with HF. Subsequent treatment of those patients with sleep apnea can significantly improve their quality of life and can decrease their mortality.

Natural killer cell cytotoxicity: a methods analysis of 51chromium release versus flow cytometry.

The purpose of this study is to describe design considerations for the use of flow cytometry (FC) compared to 51chromium (51Cr)-release assays utilizing cryopreserved peripheral blood mononuclear cells (PBMCs) to detect natural killer (NK) cell cytotoxicity. Subjects were 10 healthy women aged 18 to 39 years. Intra-assay variability between methods differed only at the lowest effector-target ratios evaluated. Interassay variability was wide but did not differ between methods. The relationship of lytic unit-10 between methods was strongly positive. Cytotoxicity detected by 51Cr release was higher than that detected by FC for all 10 subjects. Cost was comparable. However, had more assays been performed, technician time would have been greater with flow cytometry. More whole blood was needed to perform the flow cytometry cytotoxicity assay than 51Cr-release cytotoxicity assay. The authors found no compelling reason to adopt NK cell cytotoxicity by flow cytometry over 51Cr release.

Sense of coherence and quality of life in women with and without irritable bowel syndrome.

BACKGROUND: Despite ongoing physical and psychological distress, little is known about sense of coherence (SOC) and holistic quality of life (QOL) in women with irritable bowel syndrome (IBS). OBJECTIVES: The purposes of this study were to (a) describe and compare SOC and holistic QOL of women with and without IBS, and (b) examine the relationships among SOC, holistic QOL, and gastrointestinal (GI) and psychological distress symptoms. METHOD: A two-group comparison design was used to test the study hypotheses that women with IBS would have lower SOC and holistic QOL than control women without IBS, and that SOC and holistic QOL would be inversely related to GI and psychological distress. A total of 324 women were studied (n= 235 with IBS, n= 89 controls). Measures included the 13-item SOC Questionnaire, Modified Flanagan QOL Scale, Bowel Disease Questionnaire, and Symptom-Checklist-90-R. RESULTS: Both SOC and holistic QOL were lower in women with IBS (p <.001). Correlations between SOC and global distress, depression, anxiety, and somatization without GI symptoms were moderately and inversely related (r= -.64, -.64, -.53, and -.31, respectively; p <.001) in the total sample. Relationships between holistic QOL and psychological distress indicators were universally of lower magnitude (r= -.56 to -.27, p <.001). The only GI symptom indicator significantly related to SOC and holistic QOL was alternating constipation and diarrhea (tau= -.21 and -.17, respectively; p <.001). DISCUSSION: Women with IBS have a reduced SOC and holistic QOL when compared to women without IBS. It remains to be determined whether interventions targeted at enhancing SOC and holistic QOL can impact the psychological distress associated with IBS.

Logit50: a nonlinear transformation of pNN50 with improved statistical properties.

The traditional time domain heart rate variability index pNN50 is a percentage scale-based measure of large beat-to-beat changes in heart period that may reflect parasympathetic neural activity impinging on the sino-atrial node. However, pNN50 exhibits nonlinear saturation effects near 0% and 100% that may adversely affect its statistical properties. The purpose of this paper is to propose a revision of pNN50, Logit50, that is the natural logarithm of the odds of the occurrence of large beat-to-beat differences in R-R interval. Using five clinical and normal sample data sets, the revised Logit50 index is shown to retain the computational simplicity and interpretability of the pNN50, but to have better metric properties in statistical and clinical applications. In particular, the Logit50 is demonstrated to be relatively unaffected by the positive distributional skew that is common in most statistical applications of pNN50.

Natural killer cell function and psychological distress in women with and without irritable bowel syndrome.

The primary purpose of this exploratory study was to compare percentages of natural killer (NK) cells and activated NK and T cells, and both cytotoxic and in vitro cytokine production activity in women with and without symptomatic irritable bowel syndrome (IBS). A secondary purpose was to examine the relationships of psychological distress and low sense of coherence with immune function indicators and stress hormones. NK cell percentage and activity have been shown to vary in response to many psychological and physiological stressors. The authors compared 2 groups of women: symptomatic IBS (n = 12) and control (n = 12). Between-subject variability for all immune measures was large. The percentage of activated NK and Tcells was significantly lower in the IBS group compared to control (Mann-Whitney U = 30, P = 0.05). Relationships were significant between activated NK and T cell percentage and depression, anxiety, and overall distress (r = -0.54, -0.49, and -0.47, respectively, P < 0.03) and between interferon-gamma production and anxiety (r = -0.45, P < 0.03). There was a trend toward a positive relationship between sense of coherence and NK cytotoxicity (r = 0.39, P = 0.11). Thesefindings are important because they suggest that nursing interventions targeting ongoing physical and psychological distress might also be helpful in improving immune function.

The relationship between quality of life, sense of coherence and self-esteem in persons after coronary artery bypass graft surgery.

We examined the contribution of Antonovsky's sense of coherence in explaining the variance of quality of life (QOL) in 84 patients 1-2 years following coronary artery bypass graft surgery. The hypothesis was: after controlling for variables related to poor health vulnerability, perceived support, self-esteem, and chronic illness trajectory instability and work, the addition of sense of coherence will significantly add to the explained variance of quality of life. The first two variables explained 49% of the variance of the QOL scale. Adding perceived social support, self-esteem and sense of coherence increased explained variance to 64%, 69%, and 75%, respectively. These findings supported our hypothesis.