Relative adrenal insufficiency in extremely low birth weight infants may contribute to significant morbidity and death. Our objective was to evaluate the relationship between cortisol concentrations and short-term outcomes.
Cortisol concentrations were obtained for 350 intubated, extremely low birth weight infants at postnatal age of 12 to 48 hours and at day 5 to 7, as part of a multicenter, randomized trial of hydrocortisone treatment for prophylaxis of relative adrenal insufficiency. Death and short-term morbidity were monitored prospectively. Cortisol levels at each time point were divided into quartiles. The incidence rates of outcomes were determined for each quartile and for infants with cortisol values of <10th percentile or >90th percentile.
Median cortisol values were 16.0 μg/dL at baseline and 13.1 μg/dL on day 5 to 7 in the placebo group. Outcomes did not differ in each quartile between treatment and placebo groups. Low cortisol values at baseline or day 5 to 7 were not associated with increased morbidity or mortality rates and were not predictive of open-label hydrocortisone use. In fact, vasopressor use was lower for infants with lower cortisol values at baseline. Severe intraventricular hemorrhage was more frequent in infants with cortisol levels in the upper quartile at baseline, and values of >90th percentile were significantly associated with higher rates of death, severe intraventricular hemorrhage, periventricular leukomalacia, gastrointestinal perforation, and severe retinopathy of prematurity.
Low cortisol concentrations were not predictive of adverse short-term outcomes, but high cortisol concentrations were associated with severe intraventricular hemorrhage, and extremely elevated values were associated with morbidity and death. Low cortisol concentrations alone at these 2 time points did not identify the infants at highest risk for adverse outcomes. In contrast, high cortisol values were associated with increased morbidity and mortality rates.
bronchopulmonary dysplasia; extremely preterm infants; hydrocortisone; outcomes of high-risk infants
The etiologies of ischemic stroke remain undetermined in 15% to 40% of patients. Apart from atrial fibrillation, other arrhythmias are less well-characterized as risk factors. Premature cardiac contractions are known to confer long-term cardiovascular risks, like myocardial infarction. Ischemic stroke as cardiovascular risk outcome remains a topic of interest. We examined the prospective relationships in the Atherosclerosis Risk in Communities (ARIC) study, to determine whether premature atrial (PAC) or ventricular (PVC) contractions are associated with increased risk for incident ischemic stroke.
Methods and Results
We analyzed 14 493 baseline stroke-free middle-aged individuals in the ARIC public-use data. The presence of PAC or PVC at baseline was assessed from 2-minute electrocardiogram. A physician-panel confirmed and classified all stroke cases. Average follow-up time was 13 years. Proportional hazards models assessed associations between premature contractions and incident stroke. PACs and PVCs were identified in 717 (4.9%) and 793 (5.5%) participants, respectively. In all, 509(3.5%) participants developed ischemic stroke. The hazard ratio (HR) (95% confidence interval [CI]) associated with PVC was 1.77 (1.30, 2.41), attenuated to 1.25 (0.91, 1.71) after adjusting for baseline stroke risk factors. The interaction between PVC and baseline hypertension was marginally significant (P=0.08). Among normotensives, having PVCs was associated with nearly 2-fold increase in the rate of incident ischemic stroke (HR 1.69; 95% CI 1.02, 2.78), adjusting for stroke risk factors. The adjusted risk of ischemic stroke associated with PACs was 1.30 (95% CI 0.92, 1.83).
Presence of PVCs may indicate an increased risk of ischemic stroke, especially in normotensives. This risk approximates risk of stroke from being black, male, or obese in normotensives from this cohort.
brain ischemia; embolic stroke; premature atrial contraction; premature ventricular contraction; risk factors
Recent magnetic resonance imaging (MRI) studies suggest increased transverse relaxation rate (R2*) and reduced diffusion tensor imaging (DTI) fractional anisotropy (FA) values in the SN in PD. The R2* and FA changes may reflect different aspects of PD-related pathological processes (i.e., tissue iron deposition and microstructure disorganization). This study investigated the combined changes of R2* and FA in the SN in PD.
High resolution MRI (T2-weighted, T2*, and DTI) were obtained from 16 PD and 16 Controls. Bilateral SNs were delineated manually on T2-weighted images and co-registered to R2* and FA maps. The mean R2* and FA values in each SN then were calculated and compared between PD and Controls. Logistic regression, followed by ROC curve analysis, was employed to investigate the sensitivity and specificity of the combined measures for differentiating PD subjects from Controls.
Compared to Controls, PD subjects demonstrated increased R2* (p<0.0001) and reduced FA (p=0.0365) in the SN. There was no significant correlation between R2* and FA values. Logistic regression analyses indicated that the combined use of R2* and FA values provides excellent discrimination between PD and Controls (c-statistic=0.996) compared to R2* (c-statistic=0.930) or FA (c-statistic=0.742) alone.
This study shows that the combined use of R2* and FA measures in the SN of PD enhances the sensitivity and specificity in differentiating PD from Controls. Further studies are warranted to evaluate the pathophysiological correlations of these MRI measurements, and their effectiveness in assisting in diagnosing PD and following its progression.
Parkinson’s disease (PD); substantia nigra; diffusion tensor imaging (DTI); transverse relaxation rate (R2*); magnetic resonance imaging (MRI)
To improve understanding of women's use of health care before pregnancy, by analyzing how the health status and health risks of pre- and interconceptional women are associated with health services use.
Data are from a cross-sectional random-digit dial telephone survey of a representative sample of 2002 women ages 18–45 years from the Central Pennsylvania Women's Health Study (CePAWHS). A subsample of 1,325 respondents with current reproductive capacity, classified by reproductive life stage (preconceptional or interconceptional), was analyzed.
Bivariate and multiple logistic regression analyses were conducted to determine how health needs (including indices of health status and health risks related to adverse pregnancy outcomes) are associated with five indicators of health services use (receipt of a regular physical exam, obstetrician–gynecologist [ob/gyn] visit, receipt of a set of recommended screening services, receipt of health counseling services on general health topics, and receipt of pregnancy-related counseling), controlling for predisposing and enabling variables.
Only half of women at risk of pregnancy report receiving counseling about pregnancy planning in the past year. One-third of women surveyed did not receive routine physical examinations and screening services, and over half received little or no health counseling. Multivariate analyses showed that all the measures of health needs except for negative health behavior were related to some type of health services use. Psychosocial stress was associated with having a recent ob/gyn visit, with receiving general health counseling, and with receiving pregnancy planning counseling. Cardiovascular risk was positively associated with receiving general health counseling and a regular physical exam, but negatively associated with seeing an ob/gyn. Positive health behaviors were associated with receiving screening services and with receiving general health counseling. Preconceptional reproductive life stage was positively associated with receiving a regular physical exam and negatively associated with having an ob/gyn visit.
Pre- and interconceptional women with specific health care needs may not receive appropriate health care before pregnancy. Improving pregnancy experiences and outcomes requires more comprehensive preconception health care and more preventive care before the first pregnancy.
Women's health; pregnancy; preconception health; health care utilization; surveys
Systemic inflammation (SI) is associated with impairment of cardiac autonomic modulation (CAM), which is associated with cardiac disease. However, there is limited data about SI on CAM circadian pattern, which this study is aimed to investigate in a middle-aged sample. C-reactive protein (CRP) was used as a SI marker. We performed HRV analysis on each 5-minute segment RRs from of a 24-hour 12-lead ECG to obtain time and frequency domain HRV indices as measures of CAM. The circadian pattern of CAM was analyzed by a two-stage modeling. Stage one, for each individual we fit a cosine periodic model based on the 288 segments of 5-minute HRV data to produce three individual-level cosine parameters that quantity the circadian pattern: mean (M), amplitude (Â), and acrophase time (θ), measure the overall average, the amplitude of the oscillation, and the timing of the highest oscillation, respectively. Stage two, we used random-effects-meta-analysis to summarize the effects of CRP on the three circadian parameters obtained in stage one. CRP was adversely associated with lower M of log-HF, log-LF, SDNN, and RMSSD [β (SE): −0.22 (0.07) ms2, −0.20 (0.06) ms2, −3.62 (0.99) ms, and −2.32 (0.73) ms, respectively, with all p-values<0.01]. More importantly, CRP was also adversely associated with lower Â of SDNN and RMSSD [β (SE): −0.84 (0.44) ms and −0.86 (0.38) ms, respectively, both p-values<0.05]. SI is adversely associated with circadian pattern of CAM, suggesting that the cardiac risk associated with SI may be partially mediated via inflammation-related changes in CAM.
C-reactive Protein; Inflammatory Marker; Heart Rate Variability; Periodic Regression; Random-effects Model; Meta-analysis; Community Population
To describe pre-loss and post-loss grief symptoms among family members of nursing home (NH) residents with advanced dementia, and to identify predictors of greater post-loss grief symptoms.
Prospective cohort study.
22 NHs in the greater Boston area.
123 family members of NH residents who died with advanced dementia.
Pre-loss grief was measured at baseline, and post-loss grief was measured 2 and 7 months post-loss using the Prolonged Grief Disorder scale. Independent variables included resident and family member sociodemographic characteristics, resident comfort, acute illness, acute care prior to death, family member depression, and family member understanding of dementia and of resident’s prognosis.
Levels of pre-loss and post-loss grief were relatively stable from baseline to 7 months post-loss. Feelings of separation and yearning were the most prominent grief symptoms. After multivariable adjustment, greater pre-loss grief and the family member having lived with the resident prior to NH admission were the only factors independently associated with greater post-loss grief 7 months after resident death.
The pattern of grieving for some family members of NH residents with advanced dementia is prolonged and begins before resident death. Identification of family members at risk for post-loss grief during the pre-loss period may help guide interventions aimed at lessening post-loss grief.
dementia; grief; nursing homes
The occurrence of Parkinson's disease (PD) is known to be associated both with increased nigrostriatal iron content and with low serum cholesterol and PD, but there has been no study to determine a potential relationship between these two factors.
High-resolution MRI (T1-, T2, and multiple echo T2*-weighted imaging) and fasting lipid levels were obtained from 40 patients with PD and 29 healthy controls. Iron content was estimated from mean R2* values (R2* = 1/T2*) calculated for each nigrostriatal structure including substantia nigra, caudate, putamen, and globus pallidus. This was correlated with serum cholesterol levels after controlling for age, gender, and statin use.
In patients with PD, higher serum cholesterol levels were associated with lower iron content in the substantia nigra (R = −0.43, p = 0.011 for total-cholesterol, R = −0.31, p = 0.080 for low-density lipoprotein) and globus pallidus (R = −0.38, p = 0.028 for total-cholesterol, R = −0.27, p = 0.127 for low-density lipoprotein), but only a trend toward significant association of higher total-cholesterol with lower iron content in the striatum (R = −0.34, p = 0.052 for caudate; R = −0.32, p = 0.061 for putamen). After adjusting for clinical measures, the cholesterol-iron relationships held or became even stronger in the substantia nigra and globus pallidus, but weaker in the caudate and putamen. There was no significant association between serum cholesterol levels and nigrostriatal iron content for controls.
The data show that higher serum total-cholesterol concentration is associated with lower iron content in substantia nigra and globus pallidus in Parkinson's disease patients. Further studies should investigate whether this is mechanistic or epiphenomenological relationship.
For infants born extremely low birth weight (ELBW), we examined the 1) correlation between results on the Ages and Stages Questionnaire (ASQ), and the Bayley Scales of Infant Development II (BSID-II) at 18-22 months corrected age; 2) degree to which earlier ASQ assessments predict later BSID-II results; 3) impact of ASQ use on follow-up study return rates.
ASQ data were collected at 4, 8, 12, and 18-22 months corrected age. The BSID-II was completed at 18-22 months corrected age. ASQ and BSID-II 18 – 22 month sensitivity and specificity were examined. Ability of earlier ASQs to predict later BSID-II scores was examined through linear regression analyses.
ASQ sensitivity and specificity at 18-22 months were 73% and 65%, respectively. Moderate correlation existed between earlier ASQ and later BSID-II results.
For ELBW infant assessment, the ASQ cannot substitute for the BSID-II, but appears to improve tracking success.
Bayley Scales of Infant Development; Ages and Stages Questionnaire; neurodevelopment; developmental assessment; developmental screening; NICU
The goal of this study was to address the need for comprehensive reference data regarding maturational and aging effects on regional transverse relaxation rates (R2) of the brain in normal humans. Regional R2s were measured in twenty-five brain structures from a sample of seventy-seven normal volunteers 9 to 85 years of age. The relationships between regional R2 and age were determined using generalized additive models, without the constraint of a specified a priori model. Data analysis demonstrated that the brain tissue R2-age correlations followed various time courses with both linear and non-linear characteristics depending on the particular brain structure. Most anatomical structures studied exhibited non-linear characteristics, including the amygdala, hippocampus, thalamus, globus pallidus, putamen, caudate nucleus, red nucleus, substantia nigra, orbitofrontal white matter and temporal white matter. Linear trends were detected in occipital white matter and in the genu of corpus callosum. These results indicate the complexity of age-related R2 changes in the brain while providing normative reference data that can be utilized in clinical examinations and studies utilizing quantitative transverse relaxation.
To identify characteristics of nursing home (NH) residents with advanced dementia and their health care proxies (HCPs) associated with hospice referral; and examine the association between hospice use and 1) the treatment of pain and dyspnea, and 2) unmet needs during the last 7 days of life.
Prospective cohort study.
Twenty-two Boston-area NHs.
323 NH residents with advanced dementia and their HCPs.
Data were collected at baseline and quarterly up to 18 months. Hospice referral, the frequency pain and dyspnea were experienced, and treatment of these symptoms was ascertained. HCPs reported unmet needs during the last 7 days of the residents' lives for the following domains: communication, information, emotional support, and help with personal care.
Twenty-two percent of residents were referred to hospice. After multivariable adjustment, factors associated with hospice referral included: non-White race, eating problems, HCP's perception the resident's prognosis was < 6 months, and better HCP mental health. Residents on hospice were more likely to receive scheduled opioids for pain (adjusted odds ratio (AOR), 3.16; 95% confidence interval (CI95%), 1.57-6.36), and oxygen, morphine, scopolamine or hyoscyamine for dyspnea (AOR, 3.28; CI95%, 1.37-7.86). HCPs of residents on hospice reported fewer unmet needs in all domains during the last 7 days of the residents' life.
A minority of NH residents with advanced dementia received hospice care. Hospice recipients were more likely to received scheduled opioids for pain and symptomatic treatment for dyspnea, and had fewer unmet needs at the end of life.
Hospice; palliative care; Alzheimer's disease; dementia; nursing homes
Estimating life expectancy is challenging in advanced dementia, potentially limiting the use of hospice care in these patients.
To prospectively validate and compare the performance of the Advanced Dementia Prognostic Tool (ADEPT) and hospice eligibility guidelines to estimate 6-month survival in nursing home residents with advanced dementia.
Design, Setting, and Participants
A prospective cohort study conducted in 21 nursing homes in Boston, Massachusetts, of 606 residents with advanced dementia who were recruited between November 1, 2007, and July 30, 2009. Data were ascertained at baseline to determine the residents’ ADEPT score (range, 1.0-32.5; higher scores indicate worse prognosis) and whether they met Medicare hospice eligibility guidelines. Survival was followed up to 6 months.
Main Outcome Measures
Assessment and comparison of the performance of the ADEPT score and hospice guidelines to predict 6-month survival using sensitivity, specificity, and the area under the receiver operating characteristic (AUROC) curve.
At baseline, the residents’ mean (SD) ADEPT score was 10.1 (3.1) points and 65 residents (10.7%) met hospice eligibility guidelines. Over 6 months, 111 residents (18.3%) died. The AUROC for the ADEPT score’s prediction of 6-month mortality as a continuous variable was 0.67 (95% confidence interval [CI], 0.62-0.72). The AUROC for Medicare hospice eligibility guidelines was 0.55 (95% CI, 0.51-0.59), the specificity was 0.89 (95% CI, 0.86-0.92), and the sensitivity was 0.20 (95% CI, 0.13-0.28). Using a cutoff of 13.5 on the ADEPT score, which also had specificity of 0.89, the AUROC was 0.58 (95% CI, 0.54-0.63) and the sensitivity was 0.27 (95% CI, 0.19-0.36).
When prospectively validated at the bedside and used as a continuous measure, the ability of the ADEPT score to identify nursing home residents with advanced dementia at high risk of death within 6 months was modest, albeit better than hospice eligibility guidelines. Care provided to these residents should be guided by their goals of care rather than estimated life expectancy.
Estimating life expectancy is challenging in advanced dementia.
To create a risk score to estimate survival in nursing home (NH) residents with advanced dementia.
This was a retrospective cohort study performed in the setting of all licensed US NHs. Residents with advanced dementia living in US NHs in 2002 were identified using Minimum Data Set (MDS) assessments. Mortality data from Medicare files were used to determine 12-month survival. Independent variables were selected from the MDS. Cox proportional hazards regression was used to model survival. The accuracy of the final model was assessed using the area under the receiver operating characteristic curve (AUROC). To develop a risk score, points were assigned to variables in the final model based on parameter estimates. Residents meeting hospice eligibility guidelines for dementia, based on MDS data, were identified. The AUROC assessed the accuracy of hospice guidelines to predict six-month survival.
Over 12 months, 40.6% of residents with advanced dementia (n=22,405) died. Twelve variables best predicted survival: length of stay, age, male, dyspnea, pressure ulcers, total functional dependence, bedfast, insufficient intake, bowel incontinence, body mass index, weight loss, and congestive heart failure. The AUROC for the final model was 0.68. The risk score ranged from 0–32 points (higher scores indicate worse survival). Only 15.9% of residents met hospice eligibility guidelines for which the AUROC predicting six-month survival was 0.53.
A mortality risk score derived from MDS data predicted six-month survival in advanced dementia with moderate accuracy. The predictive ability of hospice guidelines, simulated with MDS data, was poor.
Survival; advanced dementia; mortality; nursing home; hospice; palliative care
Computerized, tailored interventions have the potential to be a cost-effective means to assist a wide variety of individuals with behavior change. To examine the effect of computerized tailored physical activity reports on primary care patients' physical activity at six months.
Two-group randomized clinical trial with primary care physicians as the unit of randomization. Patients were placed in the intervention (n=187) or control group (n=207) based on their physician's assignment.
Primary care physicians (n=22) and their adult patients (n=394) from Philadelphia, PA. The study and analyses were conducted from 2004-2010.
The intervention group completed physical activity surveys at baseline, one, three, and six months. Based on their responses, participants received four feedback reports at each time point. The reports aimed to motivate participants to increase physical activity, personalized to the participant's needs; they also included an activity prescription. The control group received identical procedures except they received general reports on preventive screening based on their responses to preventive screening questions.
Main outcome measure
Minutes of physical activity measured by the 7-Day Physical Activity Recall interview at six months.
Participants were 69% female, 59% African American, and had diverse educational and income levels; the retention rate was 89.6%. After adjusting for baseline levels of activity and gender, the intervention group increased their total minutes of physical activity by a mean of 133 minutes, while the control group had a mean increase of 99 minutes (p=0.39).
Although we saw an increase in physical activity within both groups, computerized tailored physical activity reports did not significantly increase physical activity levels beyond control among ethnically and socioeconomically diverse adults in primary care.
primary care issues; physical activity; behavioral medicine; randomized clinical trial
Pneumonia is common among patients with advanced dementia, especially toward the end of life. Whether antimicrobial treatment improves survival or comfort is not well understood. The objective of this study was to examine the effect of antimicrobial treatment for suspected pneumonia on survival and comfort in patients with advanced dementia.
From 2003 to 2009, data were prospectively collected from 323 nursing home residents with advanced dementia in 22 facilities in the area of Boston, Massachusetts. Each resident was followed up for as long as 18 months or until death. All suspected pneumonia episodes were ascertained, and antimicrobial treatment for each episode was categorized as none, oral only, intramuscular only, or intravenous (or hospitalization). Multivariable methods were used to adjust for differences among episodes in each treatment group. The main outcome measures were survival and comfort (scored according to the Symptom Management at End-of-Life in Dementia scale) after suspected pneumonia episodes.
Residents experienced 225 suspected pneumonia episodes, which were treated with antimicrobial agents as follows: none, 8.9%; oral only, 55.1%, intramuscular, 15.6%, and intravenous (or hospitalization), 20.4%. After multivariable adjustment, all antimicrobial treatments improved survival after pneumonia compared with no treatment: oral (adjusted hazard ratio [AHR], 0.20; 95% confidence interval [CI], 0.10–0.37), intramuscular (AHR, 0.26; 95% CI, 0.12–0.57), and intravenous (or hospitalization) (AHR, 0.20; 95% CI, 0.09–0.42). After multivariable adjustment, residents receiving any form of antimicrobial treatment for pneumonia had lower scores on the Symptom Management at End-of-Life in Dementia scale (worse comfort) compared with untreated residents.
Antimicrobial treatment of suspected pneumonia episodes is associated with prolonged survival but not with improved comfort in nursing home residents with advanced dementia.
Background: The mechanisms underlying the relationship between particulate matter (PM) air pollution and cardiac disease are not fully understood.
Objectives: We examined the effects and time course of exposure to fine PM [aerodynamic diameter ≤ 2.5 μm (PM2.5)] on cardiac arrhythmia in 105 middle-age community-dwelling healthy nonsmokers in central Pennsylvania.
Methods: The 24-hr beat-to-beat electrocardiography data were obtained using a high-resolution Holter system. After visually identifying and removing artifacts, we summarized the total number of premature ventricular contractions (PVCs) and premature atrial contractions (PACs) for each 30-min segment. A personal PM2.5 nephelometer was used to measure individual-level real-time PM2.5 exposures for 24 hr. We averaged these data to obtain 30-min average time–specific PM2.5 exposures. Distributed lag models under the framework of negative binomial regression and generalized estimating equations were used to estimate the rate ratio between 10-μg/m3 increases in average PM2.5 over 30-min intervals and ectopy counts.
Results: The mean ± SD age of participants was 56 ± 8 years, with 40% male and 73% non-Hispanic white. The 30-min mean ± SD for PM2.5 exposure was 13 ± 22 μg/m3, and PAC and PVC counts were 0.92 ± 4.94 and 1.22 ± 7.18. Increases of 10 μg/m3 in average PM2.5 concentrations during the same 30 min or the previous 30 min were associated with 8% and 3% increases in average PVC counts, respectively. PM2.5 was not significantly associated with PAC count.
Conclusion: PM2.5 exposure within approximately 60 min was associated with increased PVC counts in healthy individuals.
cardiac arrhythmia; cardiovascular disease; PAC; particulate matter; PVC
Many medications commonly used to treat chronic conditions have unclear benefits for nursing home (NH) residents with advanced dementia. This study describes the pattern and factors associated with daily medication use in this population.
Design, Setting, Participants
Residents with advanced dementia (N=323) from 22 Boston-area NHs were followed prospectively for 18 months.
Data from residents’ records were used to determine the number or daily medications, specific drugs prescribed, and use of drugs deemed ‘never appropriate’ in advanced dementia. Resident characteristics associated with the use of more daily medications and drugs deemed inappropriate were examined.
Residents were prescribed a mean of 5.9 ± 3.0 daily medications, and 37.5% received at least one medication considered ‘never appropriate’ in advanced dementia. Acetylcholinesterase inhibitors (15.8%) and lipid-lowering agents (12.1%) were the most common inappropriate drugs. Twenty-eight percent of residents took antipsychotics daily. Modest reductions of most daily medications only occurred during the last week of life. Factors independently associated with taking more daily medications included older age, male, non-white, dementia not due Alzheimer’s, better cognition, cardiovascular disease, acute illness, and hospice referral. Factors independently associated with greater likelihood of taking inappropriate medications included male, shorter NH stay, better functional status, and diabetes, while a do-not-hospitalize order was associated with a lower likelihood.
Questionably beneficial medications are common in advanced dementia, even as death approaches. Several characteristics can help identify residents at risk for greater medication burden. Medication use in advanced dementia should be tailored to the goals of care.
end-of-life care; dementia; inappropriate medication use; nursing homes; polypharmacy
The acute effects and the time course of fine particulate pollution (PM2.5) on atrial fibrillation/flutter (AF) predictors, including P-wave duration, PR interval duration, and P-wave complexity, were investigated in a community-dwelling sample of 106 nonsmokers. Individual-level 24-h beat-to-beat electrocardiogram (ECG) data were visually examined. After identifying and removing artifacts and arrhythmic beats, the 30-min averages of the AF predictors were calculated. A personal PM2.5 monitor was used to measure individual-level, real-time PM2.5 exposures during the same 24-h period, and corresponding 30-min average PM2.5 concentration were calculated. Under a linear mixed-effects modeling framework, distributed lag models were used to estimate regression coefficients (βs) associating PM2.5 with AF predictors. Most of the adverse effects on AF predictors occurred within 1.5–2 h after PM2.5 exposure. The multivariable adjusted βs per 10-µg/m3 rise in PM2.5 at lag 1 and lag 2 were significantly associated with P-wave complexity. PM2.5 exposure was also significantly associated with prolonged PR duration at lag 3 and lag 4. Higher PM2.5 was found to be associated with increases in P-wave complexity and PR duration. Maximal effects were observed within 2 h. These findings suggest that PM2.5 adversely affects AF predictors; thus, PM2.5 may be indicative of greater susceptibility to AF.
Object permanence is considered the earliest method for assessing working memory. Factors affecting object permanence performance in a sample of two hundred and thirty-three 18- to 22-month olds born with extremely low birth weight were examined. It was hypothesized that object permanence would be directly related to emotional and attention regulation, that children with lower birth weight and higher illness severity would have more difficulty on the object permanence task, and that no ethnic/racial differences would be found, as this is considered a culturally unbiased task. Attainment of object permanence had a significant positive association with emotional and attention regulation, even after controlling the medical severity and socioeconomic factors. More girls than boys passed the object permanence items. There was no ethnic/racial difference on object permanence. Our findings indicate that object permanence may be a culturally fair way of assessing development, and emotional and attention regulation are potential avenues of intervention for such skill.
early working memory; object permanence; extremely low birth weight
To examine the circadian pattern of cardiac autonomic modulation (CAM) and its attributes in general population.
We obtained 24-h beat-to-beat RR data using a high resolution 12-lead Holter ECG in a community-dwelling sample of 115 non-smokers. We performed heart rate variability (HRV) analysis on the normal RRs from each 5-min segment to obtain time-specific HRV indices: high (HF; 0.15–0.40 Hz) and low (LF; 0.04–0.15 Hz) frequency powers, standard deviation of RR intervals (SDNN), and the square root of the mean of the sum of the squared differences of the adjacent RR intervals (RMSSD). For each individual, we fit the segment-specific HRV data to a cosine periodic function, and estimated 3 individual-level cosine function parameters to quantify the circadian variation: the mean (M), amplitude (A), and acrophase (θ). We then used a random-effects meta-analysis to summarize the M, A, and θ, and their 95% confidence intervals (CI).
The mean age was 56 (SD 8) years, with 63% female and 76% white. The averages of M, A and θ (95%CI) of log HF were 3.59 (3.43–3.76) ms2, 0.61 (0.54–0.68) ms2, and 3:10 (2:25–3:55) AM, respectively, and that of RMSSD were 22.3 (20.5–24.1) ms, 6.5 (5.4–7.5) ms, 3:45 (2:55–4:35) AM, respectively. Older age is associated with lower mean of HRV. Males have higher oscillation amplitude than females. The acrophase of LF/HF was earlier in females than in males, and in younger individuals than in older individuals.
The circadian pattern of CAM can be quantified by 3 cosine parameters of HRV, which are correlated with age and gender.
Autonomic modulation; Heart rate variability; Periodic rhythm; Community population
Insulin resistance (IR) has been associated with cardiovascular diseases (CVD). Heart rate variability (HRV), an index of cardiac autonomic modulation (CAM), is also associated with CVD mortality and CVD morbidity. Currently, there are limited data about the impairment of IR on the circadian pattern of CAM. Therefore, we conducted this investigation to exam the association between IR and the circadian oscillations of CAM in a community-dwelling middle-aged sample.
Homeostasis models of IR (HOMA-IR), insulin, and glucose were used to assess IR. CAM was measured by HRV analysis from a 24-hour electrocardiogram. Two stage modeling was used in the analysis. In stage one, for each individual we fit a cosine periodic model based on the 48 segments of HRV data. We obtained three individual-level cosine parameters that quantity the circadian pattern: mean (M), measures the overall average of a HRV index; amplitude (Â), measures the amplitude of the oscillation of a HRV index; and acrophase time (θ), measures the timing of the highest oscillation. At the second stage, we used a random-effects-meta-analysis to summarize the effects of IR variables on the three circadian parameters of HRV indices obtained in stage one of the analysis.
In persons without type diabetes, the multivariate adjusted β (SE) of log HOMA-IR and M variable for HRV were -0.251 (0.093), -0.245 (0.078), -0.19 (0.06), -4.89 (1.76), -3.35 (1.31), and 2.14 (0.995), for log HF, log LF, log VLF, SDNN, RMSSD and HR, respectively (all P < 0.05). None of the IR variables were significantly associated with Â or θ of the HRV indices. However, in eight type 2 diabetics, the magnitude of effect due to higher HOMA-IR on M, Â, and θ are much larger.
Elevated IR, among non-diabetics significantly impairs the overall mean levels of CAM. However, the Â or θ of CAM were not significantly affected by IR, suggesting that the circadian mechanisms of CAM are not impaired. However, among persons with type 2 diabetes, a group clinically has more severe form of IR, the adverse effects of increased IR on all three HRV circadian parameters are much larger.
Racial differences are known to account for a higher incidence of systemic lupus erythematosus (SLE), as well as increased disease severity and mortality. The purpose of this study was to determine if there are any race-specific risk factors that affect measures of subclinical atherosclerosis in SLE patients.
Traditional and SLE-related cardiovascular disease (CVD) risk factors were assessed in 106 female SLE patients. Carotid medial intimal medial thickness (mIMT) and coronary artery calcification (CAC) were measured on all subjects. Differences were evaluated between races for all clinical, serologic, and CVD risk factors and the racial interactions with all covariables. Outcomes included mIMT and CAC.
There were no significant differences between races with regard to mIMT or CAC. Significant covariables in the final model for mIMT included age, triglycerides, glucose, and race-age and race-smoking interactions. A prediction model with fixed significant covariables demonstrated that Black subjects with a smoking history had a significantly higher mIMT than Blacks who had never smoked, an effect not seen in Whites. There were no differences between having CAC or with the CAC scores between the races. In the final model for CAC, age and SLE disease duration were significant covariables impacting CAC.
When controlling for other significant CVD covariables and interactions, Black women, but not White, with SLE with a history of smoking have higher mIMT measurements than those who have never smoked. This is the first report documenting the race-specific effect of smoking on subclinical measures of CVD in SLE.
lupus; cardiovascular; smoking; race
The mechanisms for the relationship between particulate air pollution and cardiac disease are not fully understood. Air pollution-induced myocardial ischemia is one of the potentially important mechanisms.
We investigate the acute effects and the time course of fine particulate pollution (PM2.5) on myocardium ischemic injury as assessed by ST-segment height in a community-based sample of 106 healthy non-smokers. Twenty-four hour beat-to-beat electrocardiogram (ECG) data were obtained using a high resolution 12-lead Holter ECG system. After visually identifying and removing all the artifacts and arrhythmic beats, we calculated beat-to-beat ST-height from ten leads (inferior leads II, III, and aVF; anterior leads V3 and V4; septal leads V1 and V2; lateral leads I, V5, and V6,). Individual-level 24-hour real-time PM2.5 concentration was obtained by a continuous personal PM2.5 monitor. We then calculated, on a 30-minute basis, the corresponding time-of-the-day specific average exposure to PM2.5 for each participant. Distributed lag models under a linear mixed-effects models framework were used to assess the regression coefficients between 30-minute PM2.5 and ST-height measures from each lead; i.e., one lag indicates a 30-minute separation between the exposure and outcome.
The mean (SD) age was 56 (7.6) years, with 41% male and 74% white. The mean (SD) PM2.5 exposure was 14 (22) μg/m3. All inferior leads (II, III, and aVF) and two out of three lateral leads (I and V6), showed a significant association between higher PM2.5 levels and higher ST-height. Most of the adverse effects occurred within two hours after PM2.5 exposure. The multivariable adjusted regression coefficients β (95% CI) of the cumulative effect due to a 10 μg/m3 increase in Lag 0-4 PM2.5 on ST-I, II, III, aVF and ST-V6 were 0.29 (0.01-0.56) μV, 0.79 (0.20-1.39) μV, 0.52 (0.01-1.05) μV, 0.65 (0.11-1.19) μV, and 0.58 (0.07-1.09) μV, respectively, with all p < 0.05.
Increased PM2.5 concentration is associated with immediate increase in ST-segment height in inferior and lateral leads, generally within two hours. Such an acute effect of PM2.5 may contribute to increased potential for regional myocardial ischemic injury among healthy individuals.
Dementia is a leading cause of death in the United States but is underrecognized as a terminal illness. The clinical course of nursing home residents with advanced dementia has not been well described.
We followed 323 nursing home residents with advanced dementia and their health care proxies for 18 months in 22 nursing homes. Data were collected to characterize the residents’ survival, clinical complications, symptoms, and treatments and to determine the proxies’ understanding of the residents’ prognosis and the clinical complications expected in patients with advanced dementia.
Over a period of 18 months, 54.8% of the residents died. The probability of pneumonia was 41.1%; a febrile episode, 52.6%; and an eating problem, 85.8%. After adjustment for age, sex, and disease duration, the 6-month mortality rate for residents who had pneumonia was 46.7%; a febrile episode, 44.5%; and an eating problem, 38.6%. Distressing symptoms, including dyspnea (46.0%) and pain (39.1%), were common. In the last 3 months of life, 40.7% of residents underwent at least one burdensome intervention (hospitalization, emergency room visit, parenteral therapy, or tube feeding). Residents whose proxies had an understanding of the poor prognosis and clinical complications expected in advanced dementia were much less likely to have burdensome interventions in the last 3 months of life than were residents whose proxies did not have this understanding (adjusted odds ratio, 0.12; 95% confidence interval, 0.04 to 0.37).
Pneumonia, febrile episodes, and eating problems are frequent complications in patients with advanced dementia, and these complications are associated with high 6-month mortality rates. Distressing symptoms and burdensome interventions are also common among such patients. Patients with health care proxies who have an understanding of the prognosis and clinical course are likely to receive less aggressive care near the end of life.
To evalute whether a formula could be derived using oxygen saturation (Spo2) to replace Pao2 that would allow identification of children with acute lung injury and acute respiratory distress syndrome. Definitions of acute lung injury and acute respiratory distress syndrome require arterial blood gases to determine the Pao2/Fio2 ratio of 300 (acute lung injury) and 200 (acute respiratory distress syndrome).
Post hoc data analysis of measurements abstracted from two prospective databases of randomized controlled trials.
Academic pediatric intensive care units.
A total of 255 children enrolled in two large prospective trials of therapeutic intervention for acute lung disease: calfactant and prone positioning.
Data were abstracted including Pao2, Paco2, pH, Fio2, and mean airway pressure. Repeated-measures analyses, using linear mixed-effects models, were used to build separate prediction equations for the Spo2/Fio2 ratio, oxygenation index [(Fio2 × Mean Airway Pressure)/Pao2], and oxygen saturation index [(Fio2 × Mean Airway Pressure)/Spo2]. A generalization of R2 was used to measure goodness-of-fit. Generalized estimating equations with a logit link were used to calculate the sensitivity and specificity for the cutoffs of Pao2/Fio2 ratio of 200 and 300 and equivalent values of Spo2/Fio2 ratio, oxygenation index, and oxygen saturation index.
Measurements and Main Results
An Spo2/Fio2 ratio of 253 and 212 would equal criteria for acute lung injury and acute respiratory distress syndrome, respectively. An oxygenation index of 5.3 would equal acute lung injury criteria, and an oxygenation index of 8.1 would qualify for acute respiratory distress syndrome. An oxygen saturation index, which includes the mean airway pressure and the noninvasive measure of oxygenation, of 6.5 would be equivalent to the acute lung injury criteria, and an oxygen saturation index of 7.8 would equal acute respiratory distress syndrome criteria.
Noninvasive methods of assessing oxygenation may be utilized with reasonable sensitivity and specificity to define acute lung injury and acute respiratory distress syndrome, and, with prospective validation, have the potential to increase the number of children enrolled into clinical trials.
acute lung injury; acute respiratory distress syndrome; pediatrics; oxygenation index
The mechanisms for the relationship between particulate pollution and cardiac disease are not fully understood.
We examined the effects and time course of exposure to fine particulate matter ≤ 2.5 μm in aerodynamic diameter (PM2.5) on ventricular repolarization of 106 nonsmoking adults who were living in communities in central Pennsylvania.
The 24-hr beat-to-beat electrocardiogram (ECG) data were obtained using a high-resolution 12-lead Holter system. After visually identifying and removing artifacts and arrhythmic beats, we summarized normal beat-to-beat QTs from each 30-min segment as heart rate (HR)-corrected QT measures: QT prolongation index (QTI), Bazett’s HR-corrected QT (QTcB), and Fridericia’s HR-corrected QT (QTcF). A personal PM2.5 monitor was used to measure individual-level real-time PM2.5 exposures for 24 hr. We averaged these data and used 30-min time-specific average PM2.5 exposures.
The mean age of the participants was 56 ± 8 years, with 41% male and 74% white. The means ± SDs for QTI, QTcB, and QTcF were 111 ± 6.6, 438 ± 23 msec, and 422 ± 22 msec, respectively; and for PM2.5, the mean ± SD was 14 ± 22 μg/m3. We used distributed lag models under a framework of linear mixed-effects models to assess the autocorrelation-corrected regression coefficients (β) between 30-min PM2.5 and the HR-corrected QT measures. Most of the adverse ventricular repolarization effects from PM2.5 exposure occurred within 3–4 hr. The multivariable adjusted β (SE, p-value) due to a 10-μg/m3 increase in lag 7 PM2.5 on QTI, QTcB, and QTcF were 0.08 (0.04, p < 0.05), 0.22 (0.08, p < 0.01), and 0.09 (0.05, p < 0.05), respectively.
Our results suggest a significant adverse effect of PM2.5 on ventricular repolarization. The time course of the effect is within 3–4 hr of elevated PM2.5.
autonomic modulation; cardiovascular disease; particulate matter; QT interval; ventricular repolarization