Biomedical subjects

Brydon J B Grant

Publications and source records attributed to Brydon J B Grant.

At least 19 recordsLinked to original sources

PubMed2006

Brief report: Internal medicine residents', attendings', and nurses' perceptions of the night float system.

BACKGROUND: Residency training programs use the night float system increasingly to meet the new resident work hour regulations. OBJECTIVE: To assess and compare residents', attendings', and nurses' perceptions of the night float system. DESIGN: A survey study. PARTICIPANTS: One hundred and seven residents, 48 attendings, and 69 nurses in a university-based multicenter internal medicine residency program. MEASUREMENTS: Perceived impact on patient care, resident training, and resident performance. RESULTS: The overall response rate was 75%. In general, more residents than both attendings and nurses had positive opinions regarding the night float system, particularly in relation to patient care. Only a small proportion of residents and attendings thought positively about the night float's impact on training quality (29.9%; 18.2%), daily feedback (23.0%; 9.1%), and end of rotation evaluation (21.8%; 6.1%). Less than half of the nurses had positive perceptions of the night residents' performance in terms of promptness (40.9%), physical availability (38.6%), familiarity with the patients' cases, and management plans (15.9%), communication of management plans to nurses (36.4%), professional respect and trust (43.2%), and teamwork (45.5%). CONCLUSIONS: Residents had more positive perceptions than attendings and nurses. Nurses, in particular, had negative perceptions of resident performance in the setting of the night float system.

Attitude of Health Personnel↗

PubMed2006

Pulmonary function and abdominal adiposity in the general population.

BACKGROUND: The prevalence of obesity is increasing, and there is evidence that obesity, in particular abdominal obesity as a marker of insulin resistance, is negatively associated with pulmonary function. The mechanism for this association and the best marker of abdominal adiposity in relation to pulmonary function is not known. STUDY OBJECTIVE: We assessed the association between pulmonary function and weight, body mass index (BMI), waist circumference, waist/hip ratio, and abdominal height as markers of adiposity and body fat distribution. We used multiple linear regression to analyze the association of pulmonary function (ie, FEV(1) and FVC) [with maneuvers performed in the sitting position] with overall adiposity markers (ie, weight and BMI) and abdominal adiposity markers, stratified by gender, and adjusted for height, age, race, smoking, and other covariates. SETTING AND PARTICIPANTS: A random sample of individuals (n = 2,153) from the general population living in western New York state, 35 to 79 years of age. RESULTS: In women, abdominal height and waist circumference were negatively associated with FEV(1) percent predicted, while all five adiposity markers were negatively associated with FVC percent predicted. In men, all overall and abdominal adiposity markers were inversely associated with FEV(1) percent predicted and FVC percent predicted. CONCLUSION: These results suggest that abdominal adiposity is a better predictor of pulmonary function than weight or BMI, and investigators should consider it when investigating the determinants of pulmonary function.

Abdominal Fat↗

PubMed2006

Simulated obesity-related changes in lung volume increases airway responsiveness in lean, nonasthmatic subjects.

STUDY OBJECTIVE: To determine if obesity-related changes in lung volume might contribute to airway reactivity, we investigated the effects of simulated mild obesity-related lung volume reductions on airway responsiveness in lean, nonasthmatic subjects. PARTICIPANTS AND METHODS: We simulated the lung volume reductions of class 1 obesity in eight lean, nonasthmatic subjects by externally mass loading the chest wall and abdomen, and shifting blood volume into the lung with lower limb compression (LLC). Airway responsiveness was assessed by measuring FEV(1) before and after methacholine challenge tests (1, 2.5, 5, 10, and 25 mg/mL) with the following: (1) no intervention (control); (2) external chest loading (CL); (3) LLC; and (4) CL and LLC (COMB) on separate days. Lung function was measured before and after CL, LLC, and COMB were applied. RESULTS: The application of CL, LLC, and COMB decreased expiratory reserve volume, functional residual capacity, and total lung capacity compared with baseline. FVC and FEV(1) decreased significantly with CL and COMB, while FEV(1)/FVC did not change compared to baseline. The maximal response to the methacholine challenge increased with CL, LLC, and COMB, with a mean maximal fall of FEV(1) of 9%, 11%, and 18%, respectively, compared to a 6% fall with control. CONCLUSIONS: We conclude that decreases in lung volume increase airway responsiveness and may account for the increased propensity for increased airway responsiveness in the obese.

Administration, Inhalation↗

PubMed2005

Oxidative stress and pulmonary function in the general population.

Studies have shown increased oxidative stress in patients with chronic airflow limitation; however, the population-based evidence for the association of oxidative stress with pulmonary function is limited. The authors analyzed the association of plasma thiobarbituric acid-reactive substances (TBARS), glutathione, glutathione peroxidase, and 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox)-equivalent antioxidant capacity with forced expiratory volume in 1 second and forced vital capacity using data collected from 1996 to 2000 in a general population sample from western New York State (n = 2,346). After adjustment for covariates including smoking status, lifetime pack-years of smoking, education, weight, and eosinophils, multivariate analysis showed an inverse association of TBARS with forced expiratory volume in 1 second and forced vital capacity as the percentage of the predicted value (FEV1% and FVC%, respectively), positive associations of glutathione peroxidase with FEV1% and FVC%, and an inverse association of glutathione with FEV1% in men (p < 0.05). The associations of TBARS and glutathione peroxidase with FVC% in men remained statistically significant after adjustment for serum carotenoid levels. There were no statistically significant associations of oxidative stress with pulmonary function in women. These results suggest that oxidative stress may be associated with airflow limitation in men, and that gender differences may exist in the relation of oxidative stress to pulmonary function.

Biomarkers↗

PubMed2005

Moraxella catarrhalis in chronic obstructive pulmonary disease: burden of disease and immune response.

RATIONALE: Moraxella catarrhalis is frequently present in the sputum of adults with chronic obstructive pulmonary disease (COPD). Little is known about the role of M. catarrhalis in this common disease. OBJECTIVE: To elucidate the burden of disease, the dynamics of carriage, and immune responses to M. catarrhalis in COPD. METHODS: Prospective cohort study of 104 adults with COPD in an outpatient clinic at the Buffalo Veterans Affairs Medical Center. MEASUREMENTS: Clinical information, sputum cultures, molecular typing of isolates, and immunoassays to measure antibodies to M. catarrhalis. MAIN RESULTS: Over 81 months, 104 patients made 3,009 clinic visits, 560 during exacerbations. Molecular typing identified 120 episodes of acquisition and clearance of M. catarrhalis in 50 patients; 57 (47.5%) of the acquisitions were associated with clinical exacerbations. No instances of simultaneous acquisition of a new strain of another pathogen were observed. The duration of carriage of M. catarrhalis was shorter with exacerbations compared with asymptomatic colonization (median, 31.0 vs. 40.4 days; p = 0.01). Reacquisition of the same strain was rare. The intensity of the serum IgG response was greater after exacerbations than asymptomatic colonization (p = 0.009). Asymptomatic colonization was associated with a greater frequency of a sputum IgA response than exacerbation (p = 0.009). CONCLUSIONS: M. catarrhalis likely causes approximately 10% of exacerbations of COPD, accounting for approximately 2 to 4 million episodes annually. The organism is cleared efficiently after a short duration of carriage. Patients develop strain-specific protection after clearance of M. catarrhalis from the respiratory tract.

Aged↗

PubMed2005

Weaning prediction: esophageal pressure monitoring complements readiness testing.

Several variables are recommended for identifying if a patient is ready for a trial of weaning from mechanical ventilation, but there is no agreement as to whether monitoring any variable during the trial enhances patient management. To determine whether repeated measurements of esophageal pressure throughout a trial are more reliable than measurements of esophageal pressure or frequency-to-VT ratio during the first minute of the trial, we studied 60 patients. A trend index that quantified esophageal pressure swings over time was more reliable than the first-minute measurements: sensitivity, 0.91, and specificity, 0.89. Area under receiver operating characteristic curve for trend index (0.94) was greater than for first-minute measurement of esophageal pressure (0.44, p < 0.05) and tended to be greater than that for frequency-to-VT ratio (0.78, p = 0.13). The likelihood ratio was highest for the trend index (8.2, p < 0.05). The advantage of the trend index may be related to the progressive increase in esophageal pressure throughout a failed weaning trial, whereas breathing pattern changed little after 2 minutes of spontaneous breathing. In conclusion, continuous monitoring of esophageal pressure swings during a spontaneous breathing trial provides additional guidance in patient management over tests used for deciding when to initiate weaning.

Aged↗

PubMed2005

Is being breastfed as an infant associated with adult pulmonary function?

OBJECTIVE: Breastfeeding reduces the risk of asthma and respiratory infections in infants. Since respiratory infections are associated with reduced pulmonary function in adolescents, pulmonary function impairment may be carried into adulthood. Our aim was to determine whether a history of having been breastfed as an infant is a determinant of adult pulmonary function. METHODS: We analyzed data from a general population sample of residents of Erie and Niagara Counties between September 1995 and December 1999. We calculated forced expiratory volume in one second (FEV(1)) and forced vital capacity (FVC) prediction equations and used multiple linear regression models to study the association between having been breastfed as an infant and percentage predicted FEV(1) (FEV(1)%) and percentage predicted FVC (FVC%) after adjustment for covariates. RESULTS: Of 2305 subjects, 62% reported having been breastfed. After controlling for age, gender, weight, smoking status, pack-years of smoking, eosinophil counts and dietary factors, there was no association between having been breastfed (yes/no) and FEV(1)% or FVC% (regression coefficients 0.0049, p = 0.46 and 0.0055, p = 0.43, respectively). CONCLUSIONS: We did not find a strong or consistent association between having been breastfed as an infant and pulmonary function in adulthood.

Adult↗

PubMed2005

Prevalence of positional sleep apnea in patients undergoing polysomnography.

STUDY OBJECTIVES: The primary aim of this study was to determine the prevalence of positional obstructive sleep apnea using a functional definition. Positional sleep apnea was defined as a total apnea-hypopnea index (AHI) > or = 5 with a > 50% reduction in the AHI between the supine and nonsupine postures, and an AHI that normalizes (AHI < 5) in the nonsupine posture. A secondary aim was to determine if positional sleep apnea can be diagnosed accurately during a split-night study. DESIGN: Retrospective chart review. SETTING: Two sleep centers in Buffalo, NY, one a Veterans Affairs Western New York Healthcare System Sleep Center (VAWNY) and the other a freestanding ambulatory center (Associated Sleep Center [ASC]). PATIENTS: Three hundred twenty-six patients from the VAWNY, including 57 patients who underwent a split-night study and 242 patients from the ASC who underwent polysomnography. INTERVENTIONS: None. MEASUREMENTS: Patient characteristics and sleep study results. RESULTS: Positional sleep apnea was seen in 49 of 99 patients (49.5%) with mild sleep apnea (AHI, 5 to 15/h), 14 of 72 patients (19.4%) with moderate sleep apnea (AHI, 15 to 30/h), and 5 of 77 patients (6.5%) with severe sleep apnea (AHI > 30/h). Sufficient sleep (> 15 min) in both postures was not seen in 104 of 269 patients (38.7%) and 80 of 242 overnight studies (33.1%) at the VAWNY and ASC, respectively, and was not seen in 47 of 57 split-night studies (82.5%). The percentage of studies with insufficient sleep in both postures was significantly greater for split-night studies (p < 0.0001). CONCLUSIONS: Positional sleep apnea is common particularly in patients with mild disease. Positional sleep apnea cannot usually be assessed during a split-night study.

Adult↗

PubMed2004

Systemic administration of serotonin 2A/2C agonist improves upper airway stability in Zucker rats.

The effects of [+/-]-2,5-dimethoxy-4-iodoaminophentamine, a serotonin(2A/2C) receptor agonist, on pharyngeal airflow mechanics were examined in isoflurane-anesthetized lean and obese Zucker rats. The pharyngeal pressure associated with flow limitation, maximum inspiratory flow, oronasal resistance, genioglossus muscle activity, and arterial blood pressure (BP) were measured before and after the intravenous administration of the agonist. A robust activation of the genioglossus muscle in all lean and obese rats was associated with decreased upper airway (UA) collapsibility (p < 0.05), unchanged maximum flow, and increased oronasal resistance (p < 0.05) in both groups. The changes in UA mechanics and BP after the drug were similar in lean and obese rats. The serotonin agonist had no effect on UA mechanics in a group of paralyzed (pancuronium bromide) rats, despite similar elevations in BP. There was a smaller decrease (p < 0.05) in UA collapsibility that was also associated with increased upstream resistance when the drug was administered after bilateral hypoglossal nerve transection. We conclude that systemic administration of a serotonin(2A/2C) receptor agonist improves UA collapsibility predominantly, but not exclusively, via stimulation of the hypoglossal nerves and also increases upstream resistance, at least in part, through activation of nonhypoglossal motoneuronal pools innervating the UA muscles.

Airway Resistance↗

PubMed2004

Physiologic evidence for the efficacy of positive expiratory pressure as an airway clearance technique in patients with cystic fibrosis.

BACKGROUND AND PURPOSE: Individuals with cystic fibrosis (CF) have large amounts of infected mucus in their lungs, which causes irreversible lung tissue damage. Although patient-administered positive expiratory pressure (PEP) breathing has been promoted as an effective therapeutic modality for removing mucus and improving ventilation distribution in these patients, the effects of PEP on ventilation distribution and gas mixing have not been documented. Therefore, this preliminary investigation described responses in distribution of ventilation and gas mixing to PEP breathing for patients with moderate to severe CF lung disease. SUBJECTS AND METHODS: The effects of PEP breathing on ventilation distribution, gas mixing, lung volumes, expiratory airflow, percentage of arterial blood oxyhemoglobin saturation (SpO(2)), and sputum volume were studied in 5 patients with CF (mean age=18 years, SD=4, range=13-22) after no-PEP, low-PEP (10-20 cm H(2)O), and high-PEP (>20 cm H(2)O) breathing conditions. Single-breath inert gas studies and lung function tests were performed before, immediately after, and 45 minutes after intervention. Single-breath tests assess ventilation distribution homogeneity and gas mixing by observing the extent to which an inspired test gas mixes with gas already residing in the lung. RESULTS: Improvements in gas mixing were observed in all PEP conditions. By 45 minutes after intervention, the no-PEP group improved by 5%, the low-PEP group improved by 15%, and the high-PEP group improved by 23%. Slow vital capacity increased by 1% for no PEP, by 9% for low PEP, and by 13% for high PEP 45 minutes after intervention. Residual volume decreased by 13% after no PEP, by 20% after low PEP, and by 30% after high PEP. Immediate improvements in forced expiratory flow during the middle half of the forced vital capacity maneuver (FEF(25%-75%)) were sustained following high PEP but not following low PEP. DISCUSSION AND CONCLUSION: This study demonstrated the physiologic basis for the efficacy of PEP therapy. The results confirm that low PEP and high PEP improve gas mixing in individuals with CF, and these improvements were associated with increased lung function, sputum expectoration, and SpO(2). The authors propose that improvements in gas mixing may lead to increases in oxygenation and thus functional exercise capacity.

Adolescent↗

PubMed2003

Strain-specific immune response to Haemophilus influenzae in chronic obstructive pulmonary disease.

Previous studies of immune response to Haemophilus influenzae after exacerbations of chronic obstructive pulmonary disease (COPD) have yielded contradictory results. Using homologous (infecting) strains and immunoassays to surface-exposed epitopes, we tested the hypothesis that adults with COPD make new antibodies to strain-specific, surface-exposed epitopes on H. influenzae after exacerbations. We collected clinical information, sputum, and serum monthly and during exacerbations from 81 patients with COPD over 56 months. Serum antibodies to H. influenzae after exacerbations associated with H. influenzae in sputum were detected with whole bacterial cell ELISA and bactericidal assays. An immune response to homologous H. influenzae occurred after 22 of 36 (61.1%) exacerbations with newly acquired strains compared with 7 of 33 (21.2%) exacerbations with preexisting strains (odds ratio [OR] = 4.4; 95%, 1.8 to 10.8; p = 0.001). An absence of an immune response was strongly associated with complement sensitivity (OR = 0.03; 95% confidence interval, 0.003 to 0.22; p = 0.001). New bactericidal antibodies developed after exacerbations were highly strain specific, showing bactericidal activity for only 11 of 90 (12.2%) heterologous strains. Development of an immune response to H. influenzae supports its role in causing exacerbations. The strain specificity of the immune response likely represents a mechanism of recurrent exacerbations.

Aged↗

PubMed2003

A novel approach for quality control of total lung capacity in the clinical pulmonary function laboratory: a study in a veteran population.

OBJECTIVE: Quality control in the clinical pulmonary function laboratory has been well developed for spirometry and diffusing capacity but not for the measurement of TLC. The purpose of the present study was to test two approaches to this problem. First, we compared TLC by body plethysmography (TLCb) with a value predicted from TLC measured by multibreath helium dilution (TLCm). Concordance between the measured and predicted values would imply the validity of the measurements. Second, we measured the test-retest variability of TLCb, TLCm and TLC measured by single breath helium dilution (TLCs) to assess the consistency of the measurements. METHODOLOGY: We performed a prospective study of 815 veterans. RESULTS: The prediction of TLCb from TLCm improved (r2 increased from 0.44 to 0.64) when FEV1/FVC and the difference between TLCm and TLCs were added to the model. The coefficient of variation for test-retest of TLCs, TLCm and TLCb were 8.9, 7.1 and 5.4%, respectively. Of all tests, 5.9% were inconsistent based on pathophysiology or measurement error and attributed mostly to TLCm. CONCLUSIONS: Prediction of TLCb from TLCm was not sufficiently accurate as to be useful for quality control. Comparison of TLCs, TLCm and TLCb may be useful for determining the internal data validity.

Airway Obstruction↗

PubMed2003

Relation between lung function and RBC distribution width in a population-based study.

STUDY OBJECTIVES: Pulmonary function is dependent not only on smoking, but also on nutritional status. Since an increased RBC distribution width (RDW) has been associated with nutritional deficiencies, we postulated that RDW has an inverse relation to pulmonary function. The purpose of this study was to test this hypothesis. DESIGN AND SETTING: A cross-sectional study was conducted of a random sample of the general population in western New York. PARTICIPANTS: A total of 1,616 subjects of both genders who were aged 35 to 79 years and were free of respiratory disease. INTERVENTIONS: None. MEASUREMENTS: Pulmonary function was assessed from FEV(1), FVC, height, body weight, total pack-years of smoking, smoking status, hemoglobin concentration, and hematologic indexes, eosinophil count, education, and blood levels of retinol, beta-cryptoxanthin, and vitamin E. RESULTS: We found a direct relation between RDW and the number of pack-years of smoking and smoking status, and an inverse relation between FEV(1) and FVC with RDW, even when potentially confounding variables such as smoking were taken into account. When the variability of FEV(1) due to smoking was used for comparison, an additional 27% of that variability in FEV(1) was explained by variations in antioxidant vitamin levels, and another 24% by RDW. CONCLUSIONS: The results confirmed our hypothesis that there is an inverse relation between RDW and pulmonary function, and raise the possibility that RDW may be a biomarker for as-yet unidentified nutrients that affect pulmonary function.

Adult↗

PubMed2003

Prediction of the apnea-hypopnea index from overnight pulse oximetry.

STUDY OBJECTIVE: s: To compare the relative usefulness of the different indexes derived from pulse oximetry in the diagnosis of obstructive sleep apnea (OSA), and to determine if a combination of these indexes improves the prediction of the apnea-hypopnea index (AHI) measured by polysomnography. DESIGN: Prediction model developed from 224 patients, validated prospectively in 101 patients from the same center (group 1) and in 191 patients from a different sleep center (group 2). SETTING: Two independent sleep clinics run by university sleep specialists. PARTICIPANTS: Patients who underwent polysomnography for suspicion of OSA. INTERVENTIONS: The following indexes were calculated from pulse oximetry recordings performed simultaneously during polysomnography: (1) Delta index, the average of the absolute differences of oxygen saturation between successive 12-s intervals; (2) desaturation events per hour to 2%, 3%, and 4% levels; and (3) cumulative time spent below 90%, 88%, 86%, 84%, 82%, and 80% saturation. MEASUREMENTS AND RESULTS: The best predictor was the Delta index, although desaturation events provided similar levels of diagnostic accuracy. An aggregation of multivariate models using combination of indexes reduced the prediction error (r(2) = 0.70) significantly (p < 0.05) compared to using the Delta index alone (r(2) = 0.60). The proportion of subjects from the validation groups within 95% confidence interval (CI) of the derivation group was 90% (95% CI, 83 to 95%) and 91% (95% CI, 86 to 95%) for groups 1 and 2, respectively. The overall likelihood ratios for the aggregated model in all patient groups were 4.2 (95% CI, 3.3 to 15.3), 3.4 (95% CI, 2.7 to 4.3), 3.0 (95% CI, 2.2 to 4.1), and 6.7 (95% CI, 4.9 to 9.2) for normal (AHI < 5/h), mild (AHI 5 to < 15/h), moderate (AHI 15 to < 30/h), and severe (AHI > or = 30/h) disease, respectively. CONCLUSIONS: The Delta index and oxygen desaturation indexes provided similar levels of diagnostic accuracy. The combination of indexes improved the precision of the predicted AHI and may offer a potentially simpler alternative to polysomnography.

Apnea↗

PubMed2002

Comparison of mortality between private for-profit and private not-for-profit hemodialysis centers: a systematic review and meta-analysis.

CONTEXT: Private for-profit and private not-for-profit dialysis facilities provide the majority of hemodialysis care in the United States. There has been extensive debate about whether the profit status of these facilities influences patient mortality. OBJECTIVE: To determine whether a difference in adjusted mortality rates exists between hemodialysis patients receiving care in private for-profit vs private not-for-profit dialysis centers. DATA SOURCES: We searched 11 bibliographic databases, reviewed our own files, and contacted experts in June 2001-January 2002. In June 2002, we also searched PubMed using the "related articles" feature, SciSearch, and the reference lists of all studies that fulfilled our eligibility criteria. STUDY SELECTION: We included published and unpublished observational studies that directly compared the mortality rates of hemodialysis patients in private for-profit and private not-for-profit dialysis centers and provided adjusted mortality rates. We masked the study results prior to determining study eligibility, and teams of 2 reviewers independently evaluated the eligibility of all studies. Eight observational studies that included more than 500 000 patient-years of data fulfilled our eligibility criteria. DATA EXTRACTION: Teams of 2 reviewers independently abstracted data on study characteristics, sampling method, data sources, and factors controlled for in the analyses. Reviewers resolved disagreements by consensus. DATA SYNTHESIS: The studies reported data from January 1, 1973, through December 31, 1997, and included a median of 1342 facilities per study. Six of the 8 studies showed a statistically significant increase in adjusted mortality in for-profit facilities, 1 showed a nonsignificant trend toward increased mortality in for-profit facilities, and 1 showed a nonsignificant trend toward decreased mortality in for-profit facilities. The pooled estimate, using a random-effects model, demonstrated that private for-profit dialysis centers were associated with an increased risk of death (relative risk, 1.08; 95% confidence interval, 1.04-1.13; P<.001). This relative risk suggests that there are annually 2500 (with a plausible range of 1200-4000) excessive premature deaths in US for-profit dialysis centers. CONCLUSIONS: Hemodialysis care in private not-for-profit centers is associated with a lower risk of mortality compared with care in private for-profit centers.

Health Services Research↗

PubMed2002

New strains of bacteria and exacerbations of chronic obstructive pulmonary disease.

BACKGROUND: The role of bacterial pathogens in acute exacerbations of chronic obstructive pulmonary disease is controversial. In older studies, the rates of isolation of bacterial pathogens from sputum were the same during acute exacerbations and during stable disease. However, these studies did not differentiate among strains within a bacterial species and therefore could not detect changes in strains over time. We hypothesized that the acquisition of a new strain of a pathogenic bacterial species is associated with exacerbation of chronic obstructive pulmonary disease. METHODS: We conducted a prospective study in which clinical information and sputum samples for culture were collected monthly and during exacerbations from 81 outpatients with chronic obstructive pulmonary disease. Molecular typing of sputum isolates of nonencapsulated Haemophilus influenzae, Moraxella catarrhalis, Streptococcus pneumoniae, and Pseudomonas aeruginosa was performed. RESULTS: Over a period of 56 months, the 81 patients made a total of 1975 clinic visits, 374 of which were made during exacerbations (mean, 2.1 per patient per year). On the basis of molecular typing, an exacerbation was diagnosed at 33.0 percent of the clinic visits that involved isolation of a new strain of a bacterial pathogen, as compared with 15.4 percent of visits at which no new strain was isolated (P<0.001; relative risk of an exacerbation, 2.15; 95 percent confidence interval, 1.83 to 2.53). Isolation of a new strain of H. influenzae, M. catarrhalis, or S. pneumoniae was associated with a significantly increased risk of an exacerbation. CONCLUSIONS: The association between an exacerbation and the isolation of a new strain of a bacterial pathogen supports the causative role of bacteria in exacerbations of chronic obstructive pulmonary disease.

Aged↗

PubMed2002

A systematic review and meta-analysis of studies comparing mortality rates of private for-profit and private not-for-profit hospitals.

BACKGROUND: Canadians are engaged in an intense debate about the relative merits of private for-profit versus private not-for-profit health care delivery. To inform this debate, we undertook a systematic review and meta-analysis of studies comparing the mortality rates of private for-profit hospitals and those of private not-for-profit hospitals. METHODS: We identified studies through an electronic search of 11 bibliographical databases, our own files, consultation with experts, reference lists, PubMed and SciSearch. We masked the study results before determining study eligibility. Our eligibility criteria included observational studies or randomized controlled trials that compared private for-profit and private not-for-profit hospitals. We excluded studies that evaluated mortality rates in hospitals with a particular profit status that subsequently converted to the other profit status. For each study, we calculated a relative risk of mortality for private for-profit hospitals relative to private not-for-profit hospitals and pooled the studies of adult populations that included adjustment for potential confounders (e.g., teaching status, severity of illness) using a random effects model. RESULTS: Fifteen observational studies, involving more than 26 000 hospitals and 38 million patients, fulfilled the eligibility criteria. In the studies of adult populations, with adjustment for potential confounders, private for-profit hospitals were associated with an increased risk of death (relative risk [RR] 1.020, 95% confidence interval [CI] 1.003-1.038; p = 0.02). The one perinatal study with adjustment for potential confounders also showed an increased risk of death in private for-profit hospitals (RR 1.095, 95% CI 1.050-1.141; p < 0.0001). INTERPRETATION: Our meta-analysis suggests that private for-profit ownership of hospitals, in comparison with private not-for-profit ownership, results in a higher risk of death for patients.

Hospital Mortality↗

PubMed2002

Beverage specific alcohol intake in a population-based study: evidence for a positive association between pulmonary function and wine intake.

BACKGROUND: Lung function is a strong predictor of cardiovascular and all-cause mortality. Previous studies suggest that alcohol exposure may be linked to impaired pulmonary function through oxidant-antioxidant mechanisms. Alcohol may be an important source of oxidants; however, wine contains several antioxidants. In this study we analyzed the relation of beverage specific alcohol intake with forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) in a random sample of 1555 residents of Western New York, USA. METHODS: We expressed pulmonary function as percent of predicted normal FEV1 (FEV1%) and FVC (FVC%) after adjustment for height, age, gender and race. To obtain information on alcohol intake we used a questionnaire that reliably queries total alcohol and beverage specific recent (past 30 days) and lifetime alcohol consumption. RESULTS: Using multiple linear regression analysis after adjustment for covariates (pack-years of smoking, weight, smoking status, education, nutritional factors and for FEV1%, in addition, eosinophil count), we observed no significant correlation between total alcohol intake and lung function. However, we found positive associations of recent and lifetime wine intake with FEV1% and FVC%. When we analyzed white and red wine intake separately, the association of lung function with red wine was weaker than for white wine. CONCLUSION: While total alcohol intake was not related to lung function, wine intake showed a positive association with lung function. Although we cannot exclude residual confounding by healthier lifestyle in wine drinkers, differential effects of alcoholic beverages on lung health may exist.

Journal Article↗