Caregiver-Reported Quality Measures and Their Correlates in Home Hospice Care.

Background: A majority of hospice care is delivered at home, with significant caregiver involvement. Identifying factors associated with caregiver-reported quality measures could help improve hospice care in the United States. Objectives: To identify correlates of caregiver-reported quality measures: burden, satisfaction, and quality of end-of-life (EoL) care in home hospice care. Design: A cross-sectional study was conducted from April 2017 through February 2018. Setting/Subjects: A nonprofit, urban hospice organization. We recruited caregivers whose patients were discharged from home hospice care. Eligible caregiver participants had to be 18 years or older, English-speaking, and listed as a primary caregiver at the time the patient was admitted to hospice. Measures: The (1) short version of the Burden Scale for Family Caregivers; (2) Family Satisfaction with Care; and (3) Caregiver Evaluation of the Quality of End-Of-Life Care. Results: Caregivers (n = 391) had a mean age of 59 years and most were female (n = 297, 76.0%), children of the patient (n = 233, 59.7%), and non-Hispanic White (n = 180, 46.0%). The mean age of home hospice patients was 83 years; a majority had a non-cancer diagnosis (n = 235, 60.1%), were female (n = 250, 63.9%), and were non-Hispanic White (n = 210, 53.7%). Higher symptom scores were significantly associated with greater caregiver burden and lower satisfaction with care; but not lower quality of EoL care. Caregivers who were less comfortable managing patient symptoms during the last week on hospice had higher caregiver burden, lower caregiver satisfaction, and lower ratings of quality of EoL care. Conclusion: Potentially modifiable symptom-related variables were correlated with caregiver-reported quality measures. Our study reinforces the important relationship between the perceived suffering/symptoms of patients and caregivers' hospice experiences.

Do Decision Aids Benefit Patients with Chronic Musculoskeletal Pain? A Systematic Review.

OBJECTIVE: To review the effect of patient decision aids for adults making treatment decisions regarding the management of chronic musculoskeletal pain. METHODS: We performed a systematic review of randomized controlled trials of adults using patient decision aids to make treatment decisions for chronic musculoskeletal pain in the outpatient setting. RESULTS: Of 477 records screened, 17 met the inclusion criteria. Chronic musculoskeletal pain conditions included osteoarthritis of the hip, knee, or trapeziometacarpal joint and back pain. Thirteen studies evaluated the use of a decision aid for deciding between surgical and nonsurgical management. The remaining four studies evaluated decision aids for nonsurgical treatment options. Outcomes included decision quality, pain, function, and surgery utilization. The effects of decision aids on decision-making outcomes were mixed. Comparing decision aids with usual care, all five studies that examined knowledge scores found improvement in patient knowledge. None of the four studies that evaluated satisfaction with the decision-making process found a difference with use of a decision aid. There was limited and inconsistent data on other decision-related outcomes. Of the eight studies that evaluated surgery utilization, seven found no difference in surgery rates with use of a decision aid. Five studies made comparisons between different types of decision aids, and there was no clearly superior format. CONCLUSIONS: Decision aids may improve patients' knowledge about treatment options for chronic musculoskeletal pain but largely did not impact other outcomes. Future efforts should focus on improving the effectiveness of decision aids and incorporating nonpharmacologic and nonsurgical management options.

Palliative Care Gaps in Providing Psychological Treatment: A Review of the Current State of Research in Multidisciplinary Palliative Care.

BACKGROUND: Patients with advanced illness often have high rates of psychological symptoms. Many multicomponent palliative care intervention studies have investigated the efficacy of overall symptom reduction; however, little research has focused explicitly on how interventions address psychological symptoms associated with serious illness. METHODS: The current study reviewed 59 multicomponent palliative care intervention articles and analyzed the mental health components of palliative care interventions and their outcomes in order to better understand the current state of psychological care in palliative care. RESULTS: The majority of articles (69.5%) did not provide any details regarding the psychological component delivered as part of the palliative care intervention. Most (54.2%) studies did not specify which provider on the team was responsible for providing the psychological intervention. Studies varied regarding the type of outcome measure utilized; multi-symptom assessment scales were used in 54.2% of studies, mental health scales were employed in 25.4%, quality of life and distress scales were used in 16.9%, and no psychological scales were reported in 28.8%. Fewer than half the studies (42.4%) documented a change in a psychological outcome. DISCUSSION AND CONCLUSION: The majority of analyzed studies failed to describe how psychological symptoms were identified and treated, which discipline on the team provided the treatment, and whether psychological symptoms improved as a result of the intervention. Future research evaluating the effects of palliative care interventions on psychological symptoms will benefit from using reliable and valid psychological outcome measures and providing specificity regarding the psychological components of the intervention and who provides it.

Awareness and Misperceptions of Hospice and Palliative Care: A Population-Based Survey Study.

BACKGROUND: Despite the documented benefits of palliative and hospice care on improving patients' quality of life, these services remain underutilized. Multiple factors limit the utilization of these services, including patients' and caregivers' lack of knowledge and misperceptions. OBJECTIVES: To examine palliative and hospice care awareness, misperceptions, and receptivity among community-dwelling adults. DESIGN: Cross-sectional study. SUBJECTS: New York State residents ≥18 years old who participated in the 2016 Empire State Poll. OUTCOMES MEASURED: Palliative and hospice care awareness, misperceptions, and receptivity. RESULTS: Of the 800 participants, 664 (83%) and 216 (27%) provided a definition of hospice care and palliative care, respectively. Of those who defined hospice care, 399 (60%) associated it with end-of-life care, 89 (13.4%) mentioned it was comfort care, and 35 (5.3%) reported hospice care provides care to patients and families. Of those who defined palliative care (n = 216), 57 (26.4%) mentioned it provided symptom management to patients, 47 (21.9%) stated it was comfort care, and 19 (8.8%) reported it was applicable in any course of an illness. Of those who defined hospice or palliative care, 248 (37.3%) had a misperception about hospice care and 115 (53.2%) had a misperception about palliative care. CONCLUSIONS: Most community-dwelling adults did not mention the major components of palliative and hospice care in their definitions, implying a low level of awareness of these services, and misinformation is common among community-dwelling adults. Palliative and hospice care education initiatives are needed to both increase awareness of and reduce misperceptions about these services.

Multicomponent Palliative Care Interventions in Advanced Chronic Diseases: A Systematic Review.

BACKGROUND: Many patients live with serious chronic or terminal illnesses. Multicomponent palliative care interventions have been increasingly utilized in patient care; however, it is unclear what is being implemented and who is delivering these interventions. OBJECTIVES: To (1) describe the delivery of multicomponent palliative care interventions, (2) characterize the disciplines delivering care, (3) identify the components being implemented, and (4) analyze whether the number of disciplines or components being implemented are associated with positive outcomes. DESIGN: Systematic review. STUDY SELECTION: English-language articles analyzing multicomponent palliative care interventions. OUTCOMES MEASURED: Delivery of palliative interventions by discipline, components of palliative care implemented, and number of positive outcomes (eg, pain, quality of life). RESULTS: Our search strategy yielded 71 articles, which detailed 64 unique multicomponent palliative care interventions. Nurses (n = 64, 88%) were most often involved in delivering care, followed by physicians (n = 43, 67%), social workers (n = 33, 52%), and chaplains (n = 19, 30%). The most common palliative care components patients received were symptom management (n = 56, 88%), psychological support/counseling (n = 52, 81%), and disease education (n = 48, 75%). Statistical analysis did not uncover an association between number of disciplines or components and positive outcomes. CONCLUSIONS: While there has been growth in multicomponent palliative care interventions over the past 3 decades, important aspects require additional study such as better inclusion of key groups (eg, chronic obstructive pulmonary disease, end-stage renal disease, minorities, older adults); incorporating core components of palliative care (eg, interdisciplinary team, integrating caregivers, providing spiritual support); and developing ways to evaluate the effectiveness of interventions that can be readily replicated and disseminated.

Improvement in Pain After Lumbar Spine Surgery: The Role of Preoperative Expectations of Pain Relief.

OBJECTIVES: Improvement in pain is a major expectation of patients undergoing lumbar spine surgery. MATERIALS AND METHODS: Among 422 patients, the goal of this prospective study was to measure 2-year postoperative pain and to determine whether this outcome varied according to patient and clinical characteristics, including amount of pain relief expected preoperatively. Before surgery patients completed valid questionnaires that addressed clinical characteristics and expectations for pain improvement. Two years after surgery patients reported how much pain improvement they actually received. RESULTS: The mean age was 56 years old and 55% were men. Two years after surgery 11% of patients reported no improvement in pain, 28% reported a little to moderate improvement, 44% reported a lot of improvement, and 17% reported complete improvement. In multivariable analysis, patients reported less pain improvement if, before surgery, they expected greater pain improvement (odds ratio [OR] 1.4), had a positive screen for depression (OR 1.7), were having revision surgery (OR 1.6), had surgery at L4 or L5 (OR 2.5), had a degenerative diagnosis (OR 1.6), and if, after surgery, they had another surgery (OR 2.8) and greater back (OR 1.3) and leg (OR 1.1) pain (all variables P≤0.05). CONCLUSIONS: Pain is not uncommon after lumbar surgery and is associated with a network of clinical, surgical, and psychological variables. This study provides evidence that patients' expectations about pain are an independent variable in this network. Because expectations are potentially modifiable this study supports addressing pain-related expectations with patients before surgery through discussions with surgeons and through formal preoperative patient education.

Practice-Based Research Priorities for Palliative Care: Results From a Research-to-Practice Consensus Workshop.

We employed the research-to-practice consensus workshop (RTP; workshops held in New York City and Tompkins County, New York, in 2013) model to merge researcher and practitioner views of translational research priorities in palliative care. In the RTP approach, a diverse group of frontline providers generates a research agenda for palliative care in collaboration with researchers. We have presented the major workshop recommendations and contrasted the practice-based research priorities with those of previous consensus efforts. We uncovered notable differences and found that the RTP model can produce unique insights into research priorities. Integrating practitioner-identified needs into research priorities for palliative care can contribute to addressing palliative care more effectively as a public health issue.

Assessing the role of cognition prior to transcatheter aortic valve replacement.

Transcatheter aortic valve replacement offers patients with severe aortic stenosis an opportunity to live longer and better lives. Although this procedure allows clinicians to treat sicker and frailer patients who cannot undergo open heart surgery, age-related comorbidities, specifically cognitive impairment, must factor into the evaluation process.

Integration of geriatric mental health screening into a primary care practice: a patient satisfaction survey.

OBJECTIVE: Colocation of mental health screening, assessment, and treatment in primary care reduces stigma, improves access, and increases coordination of care between mental health and primary care providers. However, little information exists regarding older adults' attitudes about screening for mental health problems in primary care. The objective of this study was to evaluate older primary care patients' acceptance of and satisfaction with screening for depression and anxiety. METHODS: The study was conducted at an urban, academically affiliated primary care practice serving older adults. Study patients (N = 107) were screened for depression/anxiety and underwent a post-screening survey/interview to assess their reactions to the screening experience. RESULTS: Most patients (88.6%) found the length of the screening to be "just right." A majority found the screening questions somewhat or very acceptable (73.4%) and not at all difficult (81.9%). Most participants did not find the questions stressful (84.9%) or intrusive (91.5%); and a majority were not at all embarrassed (93.4%), upset (93.4%), or uncomfortable (88.8%) during the screening process. When asked about frequency of screening, most patients (72.4%) desired screening for depression/anxiety yearly or more. Of the 79 patients who had spoken with their physicians about mental health during the visit, 89.8% reported that it was easy or very easy to talk with their physicians about depression/anxiety. Multivariate results showed that patients with higher anxiety had a lower positive reaction to the screen when controlling for gender, age, and patient-physician communication. CONCLUSIONS: These results demonstrate strong patient support for depression and anxiety screening in primary care.

Postoperative delirium in elderly patients after elective hip or knee arthroplasty performed under regional anesthesia.

Delirium is a major adverse postoperative event in elderly patients. Incidence rates of postoperative delirium are difficult to determine. Because of the accuracy, brevity, and ease of use by clinical interviewers, the Confusion Assessment Method (CAM) has become widely used. This study used the CAM to determine the rate of postoperative delirium in patients undergoing total hip arthroplasty (THA) and total knee arthroplasty (TKA) procedures under regional anesthesia. Following Institutional Review Board approval, a prospective study of 20 patients per group ages 70 and above undergoing unilateral THA or TKA was initiated. Both groups received a combined spinal-epidural, postoperative patient-controlled epidural anesthesia, and postoperative oral opioids. Patient interviews occurred five times: once preoperatively and two times each on postoperative days 1 and 2. Only two patients were assessed as delirious according to the CAM method (one in each group; 5%). Patient assessment by other clinicians indicated that five additional patients experienced acute change in mental status; however, these patients were not delirious at the times of the study interviews. The rate of delirium in the elderly after arthroplasty performed under regional anesthesia is very low. Reasons for this include patient selection criteria and anesthesia type. The study excluded patients with several proposed risk factors for postoperative delirium: prior history of dementia, history of mental illness, and use of benzodiazepines. The use of regional anesthesia may have also reduced the occurrence of postoperative delirium.

Preparing to implement a self-management program for back pain in new york city senior centers: what do prospective consumers think?

OBJECTIVE: Prior to testing the feasibility/potential efficacy of a newly developed self-management pain program for seniors with back pain, this study sought to: 1) determine prospective consumers' prior exposure to self-management pain programs, 2) determine their willingness to participate in the new program, and 3) ascertain perceived barriers/facilitators to program participation. DESIGN: Cross-sectional survey. SETTING: Six senior centers located in New York City. PARTICIPANTS: We enrolled a race/ethnicity stratified (African American, Hispanic, or non-Hispanic White) sample of 90 subjects who were ages 60 years or older and had chronic back pain. RESULTS: While 60% of non-Hispanic Whites reported prior participation in a self-management pain program, fewer Hispanic (23%) and African Americans (20%) participants reported prior participation. Most participants (80%) were strongly willing to participate in the new program. Multivariate analyses revealed that only pain intensity had a trend toward significance (P = 0.07), with higher pain scores associated with greater willingness to participate. Few barriers to participation were identified, however, respondents felt that tailoring the course to best meet the needs of those with physical disabilities, providing flexibility in class timing, and informing individuals about program benefits prior to enrollment could help maximize program reach. No race/ethnicity differences were identified with respect to willingness to participate or program participation barriers. CONCLUSIONS: These data support efforts to disseminate self-management pain programs in older populations, particularly minority communities. The recommendations made by participants can help to guide implementation efforts of the newly developed pain program and may help to enhance both their reach and success.

Are commonly ordered lab tests useful screens for alcohol disorders in older male veterans receiving primary care?.

Although mean corpuscular volume (MCV), aspartate aminotransferase (AST), alanine aminotransferases (ALT), and the AST/ALT ratio are sometimes used as markers of alcohol disorders, their utility has not been established in older persons. We determined the tests' performance characteristics for (1) at-risk drinking, (2) CAGE positivity, (3) at-risk drinking and CAGE positivity, and (4) a clinician-recorded diagnosis of alcohol abuse/dependence in a study of older male veterans receiving primary care. Participants (n = 587) included patients who had MCV, AST, and/or ALT data collected as part of routine care no more than 12 weeks before or after enrollment. MCV, AST, and ALT test results were obtained from the VA's database. At enrollment, the Timeline Followback and Alcohol Use Disorders Identification Test (AUDIT) were used to identify at-risk drinkers (> or = 15 drinks per week or AUDIT score > or = 8), and the CAGE questionnaire was administered to identify participants with a history abuse/dependent drinking (CAGE score > or = 2). Participants' medical records were reviewed to identify subjects with a clinician-recorded diagnosis of alcohol abuse/dependence. The prevalence of abnormal test results for MCV (threshold value = > 98), AST (> 41), ALT (> 41), and the AST/ALT ratio (> 2) was 11%, 4%, 4%, and 5%, respectively. The occurrence of at-risk drinking, CAGE positivity, at-risk drinking and CAGE positivity, and a clinician-recorded diagnosis of alcohol abuse/dependence was 11%, 25%, 5%, and 9%, respectively. Test sensitivity ranged from 3.9% to 25.4% and specificity from 88.5% to 97.1%, whereas positive likelihood ratios varied from 0.72 to 4.01 and negative likelihood ratios from 0.82 to 1.04. Areas under the receiver operating characteristic curve were similar (range = 0.50-0.58) across tests. In conclusion, MCV, AST, ALT, and the AST/ALT ratio are not useful markers of alcohol disorders in older male veterans.

Screening for alcohol problems in primary care: a systematic review.

BACKGROUND: Primary care physicians can play a unique role in recognizing and treating patients with alcohol problems. OBJECTIVE: To evaluate the accuracy of screening methods for alcohol problems in primary care. METHODS: We performed a search of MEDLINE for years 1966 through 1998. We included studies that were in English, were performed in primary care, and reported the performance characteristics of screening methods for alcohol problems against a criterion standard. Two reviewers appraised all articles for methodological content and results. RESULTS: Thirty-eight studies were identified. Eleven screened for at-risk, hazardous, or harmful drinking; 27 screened for alcohol abuse and dependence. A variety of screening methods were evaluated. The Alcohol Use Disorders Identification Test (AUDIT) was most effective in identifying subjects with at-risk, hazardous, or harmful drinking (sensitivity, 51%-97%; specificity, 78%-96%), while the CAGE questions proved superior for detecting alcohol abuse and dependence (sensitivity, 43%-94%; specificity, 70%-97%). These 2 formal screening instruments consistently performed better than other methods, including quantity-frequency questions. The studies inconsistently adhered to methodological standards for diagnostic test research: 3 (8%) provided a full description of patient spectrum (demographics and comorbidity), 30 (79%) avoided workup bias, 12 (of 34 studies [35%]) avoided review bias, and 21 (55%) performed an analysis in pertinent clinical subgroups. CONCLUSIONS: Despite methodological limitations, the literature supports the use of formal screening instruments over other clinical measures to increase the recognition of alcohol problems in primary care. Future research in this field will benefit from increased adherence to methodological standards for diagnostic tests.

Hazardous and harmful alcohol consumption in primary care.

Increasing emphasis has been placed on the detection and treatment of hazardous and harmful drinking disorders, particularly among patients who are seen in primary care settings. In this review, we summarize the epidemiology and health-related effects of hazardous and harmful drinking and discuss current methods for their detection and treatment. Hazardous drinking is defined as a quantity or pattern of alcohol consumption that places patients at risk for adverse health events, while harmful drinking is defined as alcohol consumption that results in adverse events (e.g., physical or psychological harm). Prevalence estimates range from 4% to 29% for hazardous drinking and from less than 1% to 10% for harmful drinking. Data from several recent large prospective studies suggest that alcohol consumption in quantities consistent with hazardous or harmful drinking may increase risk for adverse health events, such as hemorrhagic stroke and breast cancer. Existing screening instruments, such as the Michigan Alcoholism Screening Test (MAST) or the CAGE questionnaire, while excellent for detecting alcohol abuse or dependence, should not be used alone to screen for hazardous and harmful drinking. The Alcohol Use Disorders Identification Test (AUDIT) is currently the only instrument specifically designed to identify hazardous and harmful drinking. Treatment of these disorders in the form of brief interventions can be successfully accomplished in primary care settings, as demonstrated by a number of well-conducted randomized trials. Given its proven efficacy in the primary care setting, we recommend routine application of this treatment approach.

Hydrophobicity scale for proteins based on inverse temperature transitions.

In general, proteins fold with hydrophobic residues buried, away from water. Reversible protein folding due to hydrophobic interactions results from inverse temperature transitions where folding occurs on raising the temperature. Because homoiothermic animals constitute an infinite heat reservoir, it is the transition temperature, Tt, not the endothermic heat of the transition, that determines the hydrophobically folded state of polypeptides at body temperature. Reported here is a new hydrophobicity scale based on the values of Tt for each amino acid residue as a guest in a natural repeating peptide sequence, the high polymers of which exhibit reversible inverse temperature transitions. Significantly, a number of ways have been demonstrated for changing Tt such that reversibly lowering Tt from above to below physiological temperature becomes a means of isothermally and reversibly driving hydrophobic folding. Accordingly, controlling Tt becomes a mechanism whereby proteins can be induced to carry out isothermal free energy transduction.

Ethene (ethylene) and ethane exhalation in Ni[II]-treated rats, using an improved rebreathing apparatus.

To assess the effects of NiCl2 on lipid peroxidation, exhalation rates of ethene (ethylene) and ethane were measured in Fischer-344 rats, using modifications of a recently published rebreathing apparatus and gas chromatographic assay. Technical improvements included more efficient removal of H2O vapor, NH3, and CO2, use of economical, readily available components, convenient standardization procedure, and no necessity for a charcoal concentrator accessory for the gas chromatograph. The detection limit was one pmol ethene or ethane per five mL air sample; the within-run precision (CV) of analysis was 2.1 percent at an ethane concentration of 16 pmol per five mL sample. A minimum of eight hours post-injection was necessary for exhalation rates of ethene or ethane to become significantly increased in NiCl2-treated rats. Ethene exhalation rate was increased 2.0- to 3.5-fold at 13 to 16 and 20 to 23 hours after NiCl2 injection (0.50 or 0.75 mmol per kg, body wt, sc). Ethane exhalation rate was increased 1.5- to 1.6-fold at the lower dosage, but was not significantly increased at the higher dosage of NiCl2. This study corroborates previous reports that lipid peroxidation is enhanced in target tissues (liver, kidney, lung) of NiCl2-treated rats.

Hepatic toxicity of nickel chloride in rats.

Enhanced lipid peroxidation was observed in livers of rats killed 24 hr after sc injection of nickel chloride (NiCl2) (750 mumol per kg), as evidenced by 13-fold increase of conjugated dienes in microsomal lipids and 4-fold increase of thiobarbituric acid (TBA) chromogens in hepatic cytosol. Histologic examination of livers from rats killed one to three days after NiCl2 injection (500 mumol per kg) showed microvesicular fatty metamorphosis, mild hydropic degeneration, and foci of inflammation. Microvesicular steatosis of hepatocytes was confirmed by electron microscopy. Dose-related increases of serum aspartate aminotransferase (ALT) activity (up to 7-fold vs controls) and alanine aminotransferase (ALT) activity (up to 3-fold vs controls) were observed 24 hr after injection of NiCl2 (125 to 750 mumol per kg); diminished serum alkaline phosphatase activity (up to 72 percent reduction vs controls) was seen at NiCl2 dosages from 375 to 750 mumol per kg. Diethyldithiocarbamate did not influence the effects of NiCl2 on TBA-chromogens in liver homogenates or on serum AST and ALT activities but acted synergistically with NiCl2 to diminish serum alkaline phosphatase activity and to increase serum bilirubin concentration. This study demonstrates that parenteral administration of NiCl2 to rats produces acute hepatic toxicity, with enhanced lipid peroxidation, microvesicular steatosis, and increased serum AST and ALT activities.

Increased lipid peroxidation in tissues of nickel chloride-treated rats.

Parenteral administration of nickel chloride (NiCl2) to rats enhanced lipid peroxidation in liver, kidney, and lung (but not in brain, heart, spleen, or testis), as measured by the thiobarbituric acid reaction for malondialdehyde (MDA) and related chromogens in fresh tissue homogenates. After sc injection of NiCl2 (0.75 mmol per kg body wt), MDA concentrations in liver and kidney became significantly increased by nine h and reached peak values at 48 h. For example, in nine rats killed 48 h after the NiCl2 injection, hepatic MDA concentrations averaged 2.5 +/- 1.0 mumol per g dry wt (P less than 0.001 versus 0.5 +/- 0.3 mumol per g in 30 controls). Dose-effect relationships for lipid peroxidation in liver and kidney were observed with NiCl2 dosages ranging from 0.12 to 0.75 mmol per kg, sc. Intrarenal administration of a carcinogenic nickel compound, nickel subsulfide (Ni3S2, 0.36 mmol per kg body wt), did not affect MDA concentrations in the injected kidneys of rats killed one to 20 days post-injection. The results of this study implicate lipid peroxidation as a molecular mechanism for cell injury in acute NiCl2 poisoning, but they do not furnish any evidence that lipid peroxidation is involved in the initiation of nickel carcinogenesis.

Studies of the pathogenesis of arteriosclerosis induced in rats by intrarenal injection of a carcinogen, nickel subsulfide.

Widespread arteriosclerotic lesions were detected by histological examinations of rats killed at seven or nine weeks after an intrarenal (ir) injection of nickel subsulfide (Ni3S2, 5 mg per rat). Arteriosclerotic plaques were readily visualized by administering hematoporphyrin derivative (HPD) iv to rats at 24 hours before sacrifice. At necropsy, the major arteries were inspected under ultraviolet light, revealing patches of intense HPD-fluorescence in the arterial endothelium of Ni3S2-treated rats, but not in control rats. Consistent with previous reports, the Ni3S2-treated rats developed pronounced erythrocytosis; blood hematocrit values averaged 70 +/- 4 percent at seven weeks after ir injection of Ni3S2 (P less than 0.001 vs corresponding value of 49 +/- 2 percent in vehicle controls). At seven weeks, blood platelet counts averaged 17 percent lower and serum glucose concentrations averaged 23 percent lower in Ni3S2-treated rats than in controls; serum lipids, lipoproteins, non-protein nitrogen constituents, electrolytes, proteins, and enzymes were not significantly affected. Body weights and systolic blood pressures of rats at two, four, and six weeks after ir injection of Ni3S2 did not differ from corresponding values in controls. Addition of egg yolk to the diet caused mild hypercholesterolemia, but it did not enhance the incidence or severity of arterial lesions in Ni3S2-treated rats. These findings exclude hypertension and hyperlipidemia as pathogenic factors in Ni3S2-induced arteriosclerosis.