Interpretation of the Pattern in Rate Ratios Across Strata

The pattern in the ratio of disease rates over strata is a summary statistic used to describe the changing risk of disease in one group relative to another. While patterns of the ratios of disease rates over strata appear to correspond to specific changes in disease rates, plots of the disease rates over strata seem to contradict the information yielded by the ratios. For example, if disease rates from populations A and B have identical rates of decline (parallel lines), the difference in the rates (A - B) at each strata remains constant, while the ratio of the rates (AIB) increases over strata. Through simple algebraic manipulation, one can show that the pattern of the rate ratio is a function of the rate difference relative to the endemic disease rate. Thus, rather than describing the behavior of the disease rates, ratio patterns reflect the importance of exposure relative to the disease rate in the unexposed population

The Abnormal Measures of Iron Homeostasis in Pediatric Obesity Are Associated with the Inflammation of Obesity

Objectives. To determine if the low iron state described in obese children is associated with the chronic inflammatory state seen in obesity. Study Design. Obese children age from 2 to 19 years seen at a weight management clinic were studied prospectively. Data were collected on age, gender, BMI, BMI z-score, serum iron, ferritin, transferrin saturation, free erythrocyte protoporphyrin, high sensitivity creactive protein (hs-crp), and hemoglobin concentration. Results. 107 subjects were studied. Hs-crp levels correlated positively with BMI (P < .001) and BMI z-score (P = .005) and negatively with serum iron (P = .002). 11.2% of subjects had low serum iron. Median serum iron was significantly lower for subjects with American Heart Association high risk hs-crp values (>3 mg/L) compared to those with low risk hs-crp (<1 mg/L), (65 mcg/dL versus 96 mcg/dL, P = .016). After adjusting for age, gender, and BMI z-score, serum iron was still negatively associated with hs-crp (P = .048). Conclusions. We conclude that the chronic inflammation of obesity results in the low iron state previously reported in obese children, similar to what is seen in other inflammatory diseases

Postural Hyperventilation as a Cause of Postural Tachycardia Syndrome: Increased Systemic Vascular Resistance and Decreased Cardiac Output When Upright in All Postural Tachycardia Syndrome Variants

BACKGROUND: Postural tachycardia syndrome (POTS) is a heterogeneous condition. We stratified patients previously evaluated for POTS on the basis of supine resting cardiac output (CO) or with the complaint of platypnea or shortness of breath during orthostasis. We hypothesize that postural hyperventilation is one cause of POTS and that hyperventilation-associated POTS occurs when initial reduction in CO is sufficiently large. We also propose that circulatory abnormalities normalize with restoration of CO2. METHODS AND RESULTS: Fifty-eight enrollees with POTS were compared with 16 healthy volunteer controls. Low CO in POTS was defined by a resting supine CO /min. Patients with shortness of breath had hyperventilation with end tidal CO2 photoplethysmography, and CO was measured by ModelFlow. Systemic vascular resistance was defined as mean arterial blood pressure/CO. End tidal CO2 and cerebral blood flow velocity of the middle cerebral artery were only reduced during head-up tilt in the hyperventilation group, whereas blood pressure was increased compared with control. We corrected the reduced end tidal CO2 in hyperventilation by addition of exogenous CO2 into a rebreathing apparatus. With added CO2, heart rate, blood pressure, CO, and systemic vascular resistance in hyperventilation became similar to control. CONCLUSIONS: We conclude that all POTS is related to decreased CO, decreased central blood volume, and increased systemic vascular resistance and that a variant of POTS is consequent to postural hyperventilation

NICU Poster - 2019

NICU Poster - 2019https://scholarlycommons.libraryinfo.bhs.org/research_education/1006/thumbnail.jp

Implementation of k-Medoids Clustering Algorithm to Cluster Crime Patterns in Yogyakarta

BACKGROUND: The purpose of this pilot study was to determine if a definitive clinical trial of thiamine supplementation was warranted in patients with acute heart failure. We hypothesized that thiamine, when added to standard of care, would improve dyspnea (primary outcome) in hospitalized patients with acute heart failure. Peak expiratory flow rate, type B natriuretic peptide, free fatty acids, glucose, hospital length of stay, as well as 30-day rehospitalization and mortality were pre-planned secondary outcome measures. METHODS: This was a blinded experimental study at two urban academic hospitals. Consecutive patients admitted from the Emergency Department with a primary diagnosis of acute heart failure were recruited over 2 years. Patients on a daily dietary supplement were excluded. Randomization was stratified by type B natriuretic peptide and diabetes medication categories. Subjects received study drug (100 mg thiamine or placebo) in the evening of their first and second day. Outcome measures were obtained 8 h after study drug infusion. Dyspnea was measured on a 100-mm visual analog scale sitting up on oxygen, sitting up off oxygen, and lying supine off oxygen with 0 indicating no dyspnea. Data were analyzed using mixed-models as well as linear, negative binomial and logistic regression models to assess the impact of group on outcome measures. RESULTS: Of 130 subjects randomized, 118 had evaluable data (55 in the control and 63 in the treatment groups), 89% in both groups were adjudicated to have primarily AHF. Thiamine values increased significantly in the treatment group and were unchanged in the control group. One patient had thiamine deficiency. Only dyspnea measured sitting upright on oxygen differed significantly by group over time. No change was found for the other measures of dyspnea and all of the secondary measures. CONCLUSIONS: In mild-moderate acute heart failure patients without thiamine deficiency, a standard dosing regimen of thiamine did not improve dyspnea, biomarkers, or other clinical parameters

Indicators of compliance for developmental follow-up of infants discharged from a regional NICU

Aim: To identify factors associated with compliance of scheduled outpatient developmental follow-up appointments in an effort to better ensure future care. Methods: This retrospective observational cohort study looked at patients born between January 7th 2006 and June 30th 2007 and discharged from a regional neonatal intensive care unit (RNICU). Discharge summaries were reviewed to attain information regarding 16 patient descriptives and 12 patient morbidities. Data were recorded and analyzed utilizing the statistical software SPSS 11.5. Results: Children of older mothers were more likely to attend follow-up (compliant: 30 years vs. non-compliant: 27 years). Factors which significantly improved compliance with follow-up care were patient contact after discharge (compliant: 65% vs. non-compliant: 35%) and early intervention referral (compliant: 64% vs. non-compliant: 36%). Factors which significantly hindered compliance were maternal drug use during pregnancy (compliant: 11.8% vs. non-compliant: 88%), and patient transfer to outside NICUs [(transferred out: compliant: 3 (10.3%), non-compliant 25 (89.3%)]. Conclusions: Several factors associated with compliance have been identified. Direct patient contact after discharge positively correlated with improved follow-up attendance. The severity of patient disease in the NICU did not impact follow-up rates. As a result close attention needs to be paid to factors which influence compliance with outpatient follow-up for developmental screening.Peer Reviewe

Postsynaptic α1-Adrenergic Vasoconstriction Is Impaired in Young Patients With Vasovagal Syncope and Is Corrected by Nitric Oxide Synthase Inhibition

BACKGROUND: Syncope is a sudden transient loss of consciousness and postural tone with spontaneous recovery; the most common form is vasovagal syncope (VVS). During VVS, gravitational pooling excessively reduces central blood volume and cardiac output. In VVS, as in hemorrhage, impaired adrenergic vasoconstriction and venoconstriction result in hypotension. We hypothesized that impaired adrenergic responsiveness because of excess nitric oxide can be reversed by reducing nitric oxide. METHODS AND RESULTS: We recorded cardiopulmonary dynamics in supine syncope patients and healthy volunteers (aged 15-27 years) challenged with a dose-response using the α1-agonist phenylephrine (PE), with and without the nitric oxide synthase inhibitor N(G)-monomethyl-L-arginine, monoacetate salt (L-NMMA). Systolic and diastolic pressures among control and VVS were the same, although they increased after L-NMMA and saline+PE (volume and pressor control for L-NMMA). Heart rate was significantly reduced by L-NMMA (P\u3c0.05) for control and VVS compared with baseline, but there was no significant difference in heart rate between L-NMMA and saline+PE. Cardiac output and splanchnic blood flow were reduced by L-NMMA for control and VVS (P\u3c0.05) compared with baseline, while total peripheral resistance increased (P\u3c0.05). PE dose-response for splanchnic flow and resistance were blunted for VVS compared with control after saline+PE, but enhanced after L-NMMA (P\u3c0.001). Postsynaptic α1-adrenergic vasoconstrictive impairment was greatest in the splanchnic vasculature, and splanchnic blood flow was unaffected by PE. Forearm and calf α1-adrenergic vasoconstriction were unimpaired in VVS and unaffected by L-NMMA. CONCLUSIONS: Impaired postsynaptic α1-adrenergic vasoconstriction in young adults with VVS can be corrected by nitric oxide synthase inhibition, demonstrated with our use of L-NMMA

Congenital anomalies, prematurity, and low birth weight rates in relation to nuclear power plant proximity1)

OBJECTIVE: The objective of this study was to determine whether maternal residential proximity to a nuclear reactor is associated with prevalence of certain birth defects. STUDY DESIGN: The New York State Vital Statistics and Congenital Malformations Registry data (1992-2001) were analyzed for five Hudson Valley counties in a 20-mile radius from the Indian Point nuclear reactor (Buchanan, NY, USA). Four zones of 5-mile increments were used to categorize proximity to the reactor. Data included congenital anomalies, low birth weight, and prematurity. RESULT: Over the 10-year period, 702 malformations in 666 children were identified from a birth population of 328,124, yielding a regional rate of 2.1 major malformations per 1000 births. The prevalence of defects, low birth weight, and prematurity were not related to proximity to the nuclear power plant. CONCLUSION: These data did not substantiate an association between maternal proximity to the reactor and certain birth defects and provide baseline data for comparison in the event of a nuclear accident

Long-term Assessment of Post-Treatment Symptoms in Patients With Culture-Confirmed Early Lyme Disease

BACKGROUND: Lyme disease patients with erythema migrans are said to have post-treatment Lyme disease symptoms (PTLDS) if there is persistence of subjective symptoms for at least 6 months following antibiotic treatment and resolution of the skin lesion. The purpose of this study was to characterize PTLDS in patients with culture-confirmed early Lyme disease followed for \u3e10 years. METHODS: Adult patients with erythema migrans with a positive skin or blood culture for Borrelia burgdorferi were enrolled in a prospective study beginning in 1991 and followed up at 6 months and annually thereafter to determine the long-term outcome of this infection. The genotype of the infecting strain of B. burgdorferi was evaluated in subjects with PTLDS. RESULTS: One hundred twenty-eight subjects with culture-confirmed early Lyme disease, of whom 55% were male, were followed for a mean ± SD of 14.98 ± 2.71 years (median = 15 years; range = 11-20 years). Fourteen (10.9%) were regarded as having possible PTLDS, but only 6 (4.7%) had PTLDS documented at their last study visit. Nine (64.3%) had only a single symptom. None of the 6 with PTLDS at their last visit was considered to be functionally impaired by the symptom(s). PTLDS was not associated with a particular genotype of B. burgdorferi. CONCLUSIONS: PTLDS may persist for \u3e10 years in some patients with culture-confirmed early Lyme disease. Such long-standing symptoms were not associated with functional impairment or a particular strain of B. burgdorferi