72 research outputs found
Vitamin D status and longitudinal lung function decline in the Lung Health Study
University of Minnesota M.S. thesis. Major: Clinical Research. Advisor: Dennis Niewoehner. 1 computer file (PDF); vi, 27 pages.Low vitamin D blood levels are postulated to be a risk factor for worse lung function, largely based on cross-sectional data. We sought to use longitudinal data to test the hypothesis that baseline plasma 25-hydroxyvitamin D [25(OH)D] is lower in subjects with more rapid lung function decline, compared to those with slow lung function decline. We conducted a nested, matched case-control study in the Lung Health Study 3 cohort. Cases and controls were continuous smokers with rapid and slow lung function decline, respectively, over approximately 6 years of follow-up. We compared baseline 25(OH)D levels between cases and controls, matching on date of blood draw and clinical center. Among 196 subjects, despite rapid and slow decliners experiencing strikingly and significantly different rates of decline of forced expiratory volume in one second (-152 vs. -0.3 mL/year; p<0.001), there was no significant difference in baseline 25(OH)D levels (25.0 vs. 25.9 ng/mL; p=0.54). There was a high prevalence of vitamin D insufficiency (35%) and deficiency (31%); only 4% had a normal 25(OH)D level in the winter. Although vitamin D insufficiency and deficiency are common among continuous smokers with established mild to moderate COPD, baseline 25(OH)D levels are not predictive of subsequent lung function decline
Vitamin D and responses to inhaled fluticasone in severe chronic obstructive pulmonary disease
Ken M Kunisaki1,3, Thomas S Rector2,41Pulmonary Section, 2Center for Chronic Disease Outcomes Research and Center for Epidemiologic and Clinical Research, Minneapolis Veterans Affairs Medical Center, Minneapolis, MN, USA; 3Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, 4Department of Medicine, University of Minnesota, Minneapolis, MN, USABackground: Patients with chronic obstructive pulmonary disease (COPD) demonstrate variable responses to inhaled corticosteroids (ICS). The factors contributing to this variability are not well understood. Data from patients with asthma have suggested that low 25-hydroxyvitamin D [25(OH)D] levels contribute to a lack of ICS response in asthma. The objective of this study was to determine whether serum levels of 25(OH)D were related to ICS responses in patients with COPD.Methods: A total of 60 exsmokers with severe COPD (mean forced expiratory volume in one second [FEV1] 1.07 L, 36% of predicted) spent 4 weeks free of any ICS, followed by 4 weeks of ICS use (fluticasone propionate 500 &micro;g twice daily). Spirometry was performed prior to and after 4 weeks of ICS use. Blood 25(OH)D levels were measured prior to ICS use and examined for relationships to changes in FEV1 following the 4 weeks of ICS use.Results: The mean 25(OH)D level was 23.3 &plusmn; 9.3 ng/mL. There was a high prevalence of vitamin D insufficiency (35%) and deficiency (40%). There was no relationship between baseline 25(OH)D and changes in FEV1 following 4 weeks of ICS.Conclusion: Baseline 25(OH)D does not contribute to the variation in short-term FEV1 responses to ICS in patients with severe COPD.Keywords: COPD, androstadienes, anti-inflammatory agents, spirometr
Biomarker Associations with Insomnia and Secondary Sleep Outcomes in Persons with and without HIV in the POPPY-Sleep Sub-study: a cohort study
STUDY OBJECTIVES: We investigated associations between inflammatory profiles/clusters and sleep measures in people living with HIV and demographically-/lifestyle-similar HIV-negative controls in the Pharmacokinetic and clinical Observations in PeoPle over fiftY (POPPY)-Sleep sub-study. METHODS: Primary outcome was insomnia (Insomnia Severity Index [ISI]â„15). Secondary sleep outcomes included 7-day actigraphy (e.g. mean/standard deviation of sleep duration/efficiency), overnight oximetry (e.g. oxygen desaturation index [ODI]) and patient-reported measures (Patient-Reported Outcomes Measurement Information System (PROMIS) sleep questionnaires). Participants were grouped using Principal Component Analysis of 31 biomarkers across several inflammatory pathways followed by cluster analysis. Between-cluster differences in baseline characteristics and sleep outcomes were assessed using Kruskal-Wallis/logistic regression/Chi-squared/Fisher's exact tests. RESULTS: Of the 465 participants included (74% people with HIV, median [interquartile range] age 54 [50-60] years), only 18% had insomnia and secondary sleep outcomes suggested generally good sleep (e.g. ODI 3.1/hr [1.5-6.4]). Three clusters with distinct inflammatory profiles were identified: 'gut/immune activation' (n=47), 'neurovascular' (n=209), and 'reference' (relatively lower inflammation; n=209). The 'neurovascular' cluster included higher proportions of people with HIV, obesity (BMIâ„30Â kg/m 2), and previous cardiovascular disease, mental health disorder, and arthritis of knee/hip relative to the other two clusters. No clinically relevant between-cluster differences were observed in proportions with insomnia (17%, 18%, 20%) before (p=0.76) or after (p=0.75) adjustment for potential confounders. Few associations were observed among actigraphy, oximetry and PROMIS measures. CONCLUSIONS: Although associations could exist with other sleep measures or biomarker types not assessed, our findings do not support a strong association between sleep and inflammation in people with HIV
DOCK2 is a Rac activator that regulates motility and polarity during neutrophil chemotaxis
Neutrophils are highly motile leukocytes, and they play important roles in the innate immune response to invading pathogens. Neutrophil chemotaxis requires Rac activation, yet the Rac activators functioning downstream of chemoattractant receptors remain to be determined. We show that DOCK2, which is a mammalian homologue of Caenorhabditis elegans CED-5 and Drosophila melanogaster Myoblast City, regulates motility and polarity during neutrophil chemotaxis. Although DOCK2-deficient neutrophils moved toward the chemoattractant source, they exhibited abnormal migratory behavior with a marked reduction in translocation speed. In DOCK2-deficient neutrophils, chemoattractant-induced activation of both Rac1 and Rac2 were severely impaired, resulting in the loss of polarized accumulation of F-actin and phosphatidylinositol 3,4,5-triphosphate (PIP3) at the leading edge. On the other hand, we found that DOCK2 associates with PIP3 and translocates to the leading edge of chemotaxing neutrophils in a phosphatidylinositol 3-kinase (PI3K)âdependent manner. These results indicate that during neutrophil chemotaxis DOCK2 regulates leading edge formation through PIP3-dependent membrane translocation and Rac activation
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Identifying a Heart Rate Recovery Criterion After a 6-Minute Walk Test in COPD
Background: Slow heart rate recovery (HRR) after exercise is associated with autonomic dysfunction and increased mortality. What HRR criterion at 1-minute after a 6-minute walk test (6MWT) best defines pulmonary impairment?.
Study Design and Methods: A total of 5008 phase 2 COPDGene (NCT00608764) participants with smoking history were included. A total of 2127 had COPD and, of these, 385 were followed-up 5-years later. Lung surgery, transplant, bronchiectasis, atrial fibrillation, heart failure and pacemakers were exclusionary. HR was measured from pulse oximetry at end-walk and after 1-min seated recovery. A receiver operator characteristic (ROC) identified optimal HRR cut-off. Generalized linear regression determined HRR association with spirometry, chest CT, symptoms and exacerbations.
Results: HRR after 6MWT (bt/min) was categorized in quintiles: †5 (23.0% of participants), 6â 10 (20.7%), 11â 15 (18.9%), 16â 22 (18.5%) and â„ 23 (18.9%). Compared to HRR†5, HRRâ„ 11 was associated with (p\u3c 0.001): lower pre-walk HR and 1-min post HR; greater end-walk HR; greater 6MWD; greater FEV1%pred; lower airway wall area and wall thickness. HRR was positively associated with FEV1%pred and negatively associated with airway wall thickness. An optimal HRR †10 bt/min yielded an area under the ROC curve of 0.62 (95% CI 0.58â 0.66) for identifying FEV1\u3c 30%pred. HRRâ„ 11 bt/min was the lowest HRR associated with consistently less impairment in 6MWT, spirometry and CT variables. In COPD, HRR†10 bt/min was associated with (p\u3c 0.001): â„ 2 exacerbations in the previous year (OR=1.76[1.33â 2.34]); CATâ„ 10 (OR=1.42[1.18â 1.71]); mMRCâ„ 2 (OR=1.42[1.19â 1.69]); GOLD 4 (OR=1.98[1.44â 2.73]) and GOLD D (OR=1.51[1.18â 1.95]). HRR†10 bt/min was predicted COPD exacerbations at 5-year follow-up (RR=1.83[1.07â 3.12], P=0.027).
Conclusion: HRR†10 bt/min after 6MWT in COPD is associated with more severe expiratory flow limitation, airway wall thickening, worse dyspnoea and quality of life, and future exacerbations, suggesting that an abnormal HRR†10 bt/min after a 6MWT may be used in a comprehensive assessment in COPD for risk of severity, symptoms and future exacerbations
A case of esophageal cancer with mesojejunal lymph node metastasis after total gastrectomy
A 56-year-old man was diagnosed with esophageal cancer by upper gastrointestinal endoscopy for examination of dysphagia. The patient had undergone total gastrectomy and jejunal interposition 4Â years previously for a gastric cancer at the pT1N0M0 stage according to the UICC-TNM classification. Enhanced CT findings revealed a 3-cm-diameter mass located near the superior mesenteric artery. We conducted subtotal esophagectomy associated with partial jejunectomy including mesojejunectomy. The mass was histologically diagnosed to be mesojejunal lymph node metastasis from esophageal cancer. Mesojejunal lymph node metastasis from esophageal cancer developing after total gastrectomy has been reported in only three cases including ours. The present lymph node metastases may have occurred via the newly developed lymphatic drainage route through the esophagojejunostomy, and this metastatic lymph node can be considered the regional lymph node. Therefore, resection of the interposed jejunal limb with mesojejunectomy may be rational in surgery on esophageal cancer developing after total gastrectomy
Association between inflammatory biomarker profiles and cardiovascular risk in individuals with and without HIV
Background:
People with HIV have an increased risk for cardiovascular morbidity and mortality. Inflammation and immune activation may contribute to this excess risk.
Methods:
We assessed thirty-one biomarkers in a subset of POPPY participants and identified three distinct inflammatory profiles: âgut/immune activationâ, âneurovascularâ, and âreferenceâ (relatively low levels of inflammation). Ten-year CVD risk predictions were calculated using the QRISK, Framingham Risk Score (FRS) and the Data Collection on Adverse effects of anti-HIV Drugs (D:A:D) algorithms. The distributions of CVD risk scores across the different inflammatory profiles, stratified by HIV status, were compared using median quantile regression.
Results:
Of the 312 participants included (70% living with HIV, median [interquartile range; IQR] age 55 [51â60] years; 82% male; 91% white), 146, 36, and 130 were in the âgut/immune activationâ, âneurovascularâ, and âreferenceâ cluster, respectively. The median [IQR] QRISK scores were 9.3% (4.5â14.5) and 10.2% (5.5â16.9) for people with and without HV, respectively, with similar scores obtained with the FRS and D:A:D. We observed statistically significant differences between the distributions of scores in the three clusters among people with HV. In particular, median QRISK (5.8% [1.0â10.7] and 3.1% [0.3â5.8]) scores were higher, respectively, for those in the âgut/immune activationâ and âneurovascularâ clusters compared to those in the reference cluster.
Conclusions:
People with HIV with increased gut/immune activation have a higher CVD risk compared to those with relatively low inflammation. Our findings highlight that clinically important inflammatory subgroups could be useful to differentiate risk and maximise prediction of CVD among people with HIV
Sleep health and cognitive function among people with and without HIV: the use of different machine learning approaches
Study objectives
We investigated associations between actigraphy-assessed sleep measures and cognitive function in people with and without HIV using different analytical approaches to better understand these associations and highlight differences in results obtained by these approaches.
Methods
Cognitive and 7-day/night actigraphy data were collected from people with HIV (PWH) and lifestyle-similar HIV-negative individuals from HIV and sexual health clinics in UK/Ireland. A global cognitive T-score was obtained averaging the standardized individual cognitive test scores accounting for socio-demographics. Average and standard deviation (SD) of eleven sleep measures over 7-days/nights were obtained. Rank regression, partial least-squares (PLS) regression, random forest, sleep dimension construct, and latent class analysis (LCA) were applied to evaluate associations between global T-scores and sleep measures.
Results
In 344 PWH (median age 57 years, 86% males), average sleep duration, efficiency and wake after sleep onset were not associated with global T-scores according to rank regression (p=0.51, p=0.09, p=0.16, respectively). In contrast, global T-scores associated with average and SD of length of nocturnal awakenings, SD of maintenance efficiency and average out-of-bed time when analyzed by PLS regression and random forest. No associations were found when using sleep dimensions or LCA. Overall, findings observed in PWH were similar to those seen in HIV-negative individuals (median age 61 years, 67% males).
Conclusions
Using multivariable analytical approaches, measures of sleep continuity, timing and regularity were associated with cognitive performance in PWH, supporting the utility of newer methods of incorporating multiple standard and novel measures of sleep-wake patterns in assessment of health and functioning
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