Disturbed sleep and preterm birth: a potential relationship?

PURPOSE: Many women report disturbed sleep during pregnancy, but its impact on clinical outcomes remains unknown. This study examined subjective sleep quality and daytime sleepiness in relation to preterm birth. METHODS: A convenience sample of 220 pregnant women completed the Pittsburgh Sleep Quality Index (PSQI), the Epworth Sleepiness Scale (ESS), and the Perceived Stress Scale (PSS) during the second trimester. Women who had preterm and full-term births were compared on these measures. RESULTS: The preterm birth rate of the sample was 14.6%. Sleep latency, the period from lights out to sleep onset, was significantly longer in the preterm group, which also reported a tendency to use more sleep medications, but had lower PSQI daytime dysfunction scores. Perceived stress did not differentiate preterm and full-term groups. CONCLUSION: Disturbed sleep in pregnancy may be associated with preterm birth. Future studies should examine specific physiological factors that underlie this increased vulnerability.

Survival by time of day of hemodialysis in an elderly cohort.

CONTEXT: Patients with end-stage renal disease (ESRD) typically undergo hemodialysis (HD) during the morning or afternoon, with time of treatment generally based on space availability or patient preference. No studies have investigated variation in patient survival as a function of the time of day when they receive dialysis. OBJECTIVE: To investigate the association of elderly patients' HD treatment shift with their continued survival, controlling for well-established HD-related mortality risk factors. DESIGN, SETTING, AND PARTICIPANTS: An 11-year follow-up cohort study conducted among 242 ESRD patients aged 60 years or older who underwent HD at 58 dialysis facilities in Georgia either during a morning shift (n = 167) or an afternoon shift (n = 75) and who completed baseline (1988) [corrected] and follow-up (1991) interviews. MAIN OUTCOME MEASURE: Mortality from all causes occurring through July 7, 1999, as verified by death-certificate reviews, and compared by morning vs afternoon-shift HD. RESULTS: Morning-shift HD patients survived significantly longer than afternoon-shift patients (median survival, 941 days vs 470 days; P<.001). A Cox proportional hazards model indicated that the morning shift was protective (relative risk, 0.71; 95% confidence interval, 0.53-0.95) independent of age, race, sex, body mass index, functional status, diabetic ESRD, cardiovascular comorbidity, weekly hours of dialysis, and months of dialysis. CONCLUSIONS: Possible explanations for differential survival in association with morning vs afternoon dialysis include salutary effects of sleep in the morning or less efficient biochemical exchange during afternoon dialysis. Results from this cohort study may warrant prospective observational studies and randomized clinical trials that systematically alter the time of day at which HD is administered.

Hemodialysis disrupts basic sleep regulatory mechanisms: building hypotheses.

BACKGROUND: The proposition that hemodialysis may induce alterations in the sleep-wake cycle is based on two clinical observations: (a) Patients on dialysis frequently sleep during and after dialysis, and (b) the procedure often is associated with temperature elevations. A review of pertinent literature showed that sleepiness and temperature are physiologically related, and that these two variables are important indicators of sleep and circadian regulatory processes. OBJECTIVES: To describe possible associations among hemodialysis, body temperature, and sleepiness; to assist in building hypotheses; and to provide direction for future research. METHODS: Three exploratory studies were performed to investigate (a) dialysis-associated elevations in body temperature, (b) changes in body temperature patterns across the day, and (c) alterations in daytime sleepiness. RESULTS: The current study demonstrated that many patients manifest dialysis-associated episodic elevations of body temperature, changes in the circadian pattern of body temperature, and increases in daytime sleep propensity. In the context of the Two-Process Model of Sleep Regulation, these alterations provide a parsimonious explanation for the poor subjective sleep quality, prolonged sleep latency, and daytime sleepiness reported by these patients. CONCLUSIONS: These preliminary studies lead to the suggestion that hemodialysis may disrupt basic sleep regulatory mechanisms, and that further investigation in this area is warranted.

Intradialytic subjective sleepiness and oral body temperature.

STUDY OBJECTIVES: Hemodialysis (HD) patients are often observed to sleep during treatment. Because of the well-described, inverse association between body temperature and sleep propensity, the purpose of this study was to describe the course of intradialytic (during HD) subjective sleepiness and examine its relationship to oral body temperature. In addition, we sought to determine if that relationship varied with dialysis treatment time of day. DESIGN: Subjective sleepiness and oral body temperature were recorded every 15 minutes through the entire course of HD. SETTING: The study was conducted at two large, inner-city dialysis units. PATIENTS OR PARTICIPANTS: The sample included 60 chronic HD patients, 20 on each of three shifts based on treatment time of day (shift 1-6:00A.M. to 10:00A.M.; shift 2-10:00A.M. to 2:00P.M.; and shift 3-2:00P.M. to 6:00P.M.. MEASUREMENTS AND RESULTS: Subjects on shift 1 were found to have a mean intradialytic sleepiness level greater than those on shift 2 (p<.04) and shift 3 (p<.003). Irrespective of shift, sleepiness increased during the first half of dialysis and decreased slightly as treatment progressed, a significant quadratic trend (p<.001). During the same period, temperature initially increased, subsequently dropped in temporal proximity to maximal sleepiness and increased again, a significant quadratic trend (p<.02). The relationship between sleepiness and temperature revealed a significant negative correlation (r=-.59, p<.03) and did not vary with treatment time of day. CONCLUSIONS: The results argue that sleep propensity increases during HD, an effect that may be related to treatment induced alterations in arousal and/or thermoregulatory processes. The effect is unrelated to treatment time of day.

Comparison of subjective sleep quality in patients with cancer and healthy subjects.

PURPOSE/OBJECTIVES: To compare the subjective sleep quality of a group of patients with cancer undergoing treatment and a normative sample of healthy comparison subjects. DESIGN: Secondary analysis of data from a single time point in a repeated measures descriptive-correlational study. SAMPLE/SETTING: Convenience sample of 15 patients with cancer receiving antineoplastic therapy and admitted to a tertiary university medical center for fever or neutropenia and 52 healthy comparison subjects without sleep disturbances. Although both groups were of similar age, a higher percentage of men comprised the comparison group. METHODS: Patients completed the Pittsburgh Sleep Quality Index (PSQI) on the first day of hospitalization to reflect their perceptions of sleep for the month prior to hospitalization. Healthy comparison subject scores on the PSQI were obtained from a published report outlining psychometric properties of the PSQI (Buysse, Reynolds, Monk, Berman, & Kupfer, 1989). MAIN RESEARCH VARIABLES: Sleep latency, sleep duration, sleep efficiency, sleep disturbances, medication use, daytime dysfunction, and global sleep quality. FINDINGS: Patients with cancer reported significantly poorer overall sleep quality accompanied by more daytime dysfunction. The incidence of specific sleep disturbances, such as snoring and dyspnea, was not different between the groups. CONCLUSIONS: This small sample of patients reported significantly poorer sleep quality than an historical comparison group. Specific sleep disturbances commonly seen in the general population were not problematic for the patients with cancer. Limited sample size and use of an historical comparison group need to be considered in interpreting and applying these findings. Additional research is needed to further characterize the nature of sleep problems in patients with cancer. IMPLICATIONS FOR NURSING PRACTICE: Nurses need to assess sleep in their patients, including its impact on quality of life and functional status.

A blueprint for reducing turnover among nursing assistants: a Louisiana study.

For decades, various exposes and reports have painted an unflattering portrait of the nursing home industry across the nation. Nursing homes in Louisiana have endured their fair share of publicity and criticism. The industry in this state has been accused of being preoccupied with profits rather than quality resident care. And, while there is much debate as to the validity of this complaint, there is solid agreement that competent and stable nursing assistants are the key to quality resident care. Unfortunately, the annual turnover rate of these essential employees ranges from 50% to 400%, nationally. This research identified the factors most responsible for the rate of turnover of nursing assistants employed in Louisiana nursing homes. Based upon the results of this study, pay, benefits, workload, and employee-employer relations, are not related to turnover. The analysis revealed that only three issues are associated with turnover--the number of beds, the number of beds per registered nurse, and the number of beds per social service worker. The message is clear: nursing home administrators must be very careful in stretching such resources. The number of beds assigned to an RN, and, in particular, the number of beds per social service worker are management issues that, if overextended, risk the turnover of nursing assistants.

Safety and efficacy of low-dose subcutaneous erythropoietin in hemodialysis patients.

Anemia in hemodialysis patients is effectively treated by intravenous (IV) injections of recombinant human erythropoietin (rHuEPO) at each dialysis session. Because the hormone is effective by subcutaneous (SC) administration, it was decided that this study would evaluate low-dose weekly SC rHuEPO therapy. To determine the safety and efficacy of weekly SC rHuEPO administration to hemodialysis patients, only one third the weekly IV dose was given and the effects were compared with those from an age-, gender-, and nephrologic disease-matched control group treated in the standard fashion. Forty-four patients entered the trial and 27 completed the protocol along with 27 control subjects. During Phase 1, experimental and control subjects received standard IV rHuEPO at dialysis for 6 months. During Phase 2, experimental patients received weekly SC rHuEPO at one third the weekly IV dose for 10 months; control subjects continued to receive IV therapy. In Phase 3, both groups were treated for 6 more months with IV rHuEPO. In Phase 2, there was no significant reduction in hematocrit value, reticulocyte count, transferrin saturation, or ferritin level in the experimental group, even with only one third the weekly rHuEPO IV dose over the 10-month period. There were no significant differences between IV and SC rHuEPO administration or between experimental and control subjects in blood pressure, serum chemistries, or parameters of "dialysis adequacy." It was concluded that low-dose weekly SC rHuEPO administration is a safe and effective method for maintaining the hematocrit level of stable hemodialysis patients. This therapy could enhance the efficacy of rHuEPO and substantially reduce costs while preserving patient care outcomes.

Sleep and dialysis: a research-based review of the literature.

Textbook descriptions of dialysis patients have long included features of insomnia, day-night reversal, and disturbed sleep. Moore recently, a very high prevalence of subjective sleep complaints and specific primary sleep disorders such as sleep apnea syndrome, periodic leg movement disorder, and restless legs syndrome have been documented in the population. These problems may in part be responsible for the low rehabilitation rate seen in ESRD patients. The purpose of this article is to assist dialysis nurses in their efforts to better understand the sleep alterations experienced by their patients by presenting a succinct review of the research literature. The major topics of discussion include: the prevalence and importance of sleep complaints in dialysis patients; subjective features and related factors; polysomnographic features; and contributing factors.

Promoting sleep and rest in critically ill patients.

The circumstances surrounding the admission of a patient to a critical care unit have a particularly negative effect on both the quantity and quality of sleep. Critical care nurses play an important and challenging role in the promotion of effective sleep and rest. Developing a plan of care that not only addresses the acute, life-threatening needs of patients but also promotes sleep and rest may seem impossible. This article provides a brief review of normal sleep, discusses barriers to sleep and rest in the critical care setting, and presents research-based interventions to promote sleep.

Purification of homogeneity and amino acid sequence analysis of a receptor protein for interleukin 1.

The interleukin 1 (IL-1) receptor from mouse EL-4 thymoma cells was purified to homogeneity by a method which utilized ligand affinity chromatography and classical chromatographic techniques. After solubilization of the receptor from intact cells with the zwitterionic detergent 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate, the IL-1 binding activity was purified greater than 23,000-fold. Analysis of the purified protein by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, immunoblot, and ligand blot demonstrated that a single protein of molecular mass of approximately 80 kDa is the IL-1 binding polypeptide. The purified protein bound IL-1 with a dissociation constant of approximately 1.1 X 10(-10) M, which is indistinguishable from the affinity of the cell-bound receptor. The amino acid composition of this protein is strikingly similar to the composition deduced from the sequence of a cDNA coding for an IL-1 receptor from EL-4 cells. Protein sequence analysis of Staphylococcus aureus V-8 protease-derived peptides yields data consistent with the sequence proposed from cloned cDNA. These studies have demonstrated that the high affinity IL-1 receptor on EL-4 cells is the 80-kDa protein.

Two high-affinity interleukin 1 receptors represent separate gene products.

Interleukin 1 (IL-1) is a polypeptide hormone that mediates a broad range of biological activities and interacts with surface receptors on numerous cell types. Equilibrium binding studies have identified a class of IL-1 receptors on T cells, fibroblasts, and epithelial cells that have 2- to 5-fold higher affinity than the receptors on bone marrow cells, pre-B cells, and macrophage cell lines. Affinity cross-linking with human 125I-labeled IL-1 alpha (125I-IL-1 alpha) labels an approximately 100-kDa protein on T cells and fibroblasts and an approximately 80-kDa protein on pre-B cells and macrophage cell lines. Monoclonal and polyclonal antibodies specific for the IL-1 receptor on T cells and fibroblasts block human 125I-IL-1 alpha binding to T cells, fibroblasts, and epithelial cells but cannot block IL-1 binding to bone marrow cells, pre-B cells, and macrophages. These antibodies immunoprecipitate the IL-1 receptor-human 125I-IL-1 alpha complex from T cells and fibroblasts but not from pre-B cells and macrophage cell lines. An S1 nuclease protection assay demonstrated that T cells and fibroblasts contain identical IL-1 receptor mRNA but that pre-B cells and macrophages do not contain this receptor mRNA. Taken together, the data demonstrate that mouse T cells, fibroblasts, and epithelial cells express an identical IL-1 receptor, whereas the IL-1 receptor on pre-B cells, macrophages, and bone marrow cells represents a different gene product.

Human interleukin-1 alpha is chemotactic for normal human keratinocytes.

Interleukin-1 (IL-1) has been shown to have mitogenic and chemotactic properties for a variety of cell types includes keratinocytes. These studies suggested that keratinocytes possess receptors for IL-1. In this study, the chemotactic properties of IL-1 for keratinocytes were confirmed and IL-1 receptors were demonstrated on keratinocytes using a radio receptor assay. Crosslinking studies with IL-1 alpha identified two major bands of Mr 97 kDa and 133 kDa. Thus, keratinocytes possess high affinity IL-1 receptors and respond to IL-1 by directed migration.

Presence of IL-1 receptors on human and murine neutrophils. Relevance to IL-1-mediated effects in inflammation.

Inflammatory responses are characterized by the infiltration of polymorphonuclear neutrophils (PMN) at the involved site. IL-1 may have an important role in mediating this response, but whether IL-1 acts directly on PMN is controversial. In this study, we examined PMN for the presence of IL-1R and determined the effect of IL-1 on PMN migration in vivo. Thioglycollate, proteose-peptone, or IL-1 elicited peritoneal exudate cells were found to bind 125I-IL-1 alpha in a specific and saturable manner. This binding was localized to the PMN in the exudate. Scatchard plot analysis indicates the presence of approximately 1700 receptors per PMN and an apparent dissociation constant of 3.0 x 10(-10) M. Binding sites for 125I-IL-1 alpha were also found on human PMN prepared from peripheral blood. There are approximately 900 receptors per cell on human PMN with a dissociation constant similar to that observed for elicited murine PMN. Binding of 125I-IL-1 alpha to the mouse and human PMN is inhibited by both recombinant human IL-1 alpha and IL-1 beta, indicating that both IL-1 proteins bind to the same receptor on these cells. Human PMN were able to internalize radioiodinated IL-1. We conclude that PMN possess receptors for IL-1 and that these binding sites may be important in mediating IL-1 effects on granulocytes that are involved in the inflammatory response.

Anxiety and complications in patients on hemodialysis.

Approximately 175 patients at a dialysis unit were screened for entrance into the study; 43 patients were accepted according to the research criteria. These 43 subjects were given the trait anxiety test from the State-Trait Anxiety Inventory by Spielberger, Gorsuch, and Lushene (1968). Subsequently, the subjects with the ten lowest and ten highest scores were followed over two months or a total of 454 dialyses, and observed for hospitalizations, clinic appointments for treatment, and deaths. During dialysis they were observed for: hypotension; nausea and vomiting; fluid overload; infection of vascular access; clotting of vascular access; epistaxis; pain; pruritus; muscle cramps; and headache. The low anxiety group was found to have a significantly greater incidence of hypotension while the high anxiety group had a greater incidence of clinic appointments for treatment, fluid overload, and cramps. The latter group also had a significantly greater incidence of total complications with the exception of hypotension. Implications were made that appropriate nursing intervention might help prevent physical discomforts in patients on hemodialysis.