Impact Of Different Definitions Research Articles

Impact of the method of calculating 30-day readmission rate after hospitalization for heart failure. Data from the VancOuver CoastAL Acute Heart Failure (VOCAL-AHF) registry.

Thirty-day readmission rate after heart failure (HF) hospitalization is widely used to evaluate healthcare quality. Methodology may substantially influence estimated rates. We assessed the impact of different definitions on HF and all-cause readmission rates. Readmission rates were examined in 1,835 patients discharged following HF hospitalization using 64 unique definitions derived from five methodological factors: (1) ICD-10 codes (broad vs narrow), (2) index admission selection (single admission only first-in-year vs. random sample; or multiple admissions in year with vs. without 30-day blanking period), (3) variable denominator (number alive at discharge vs. number alive at 30-days), (4) follow-up period start (discharge date vs day following discharge), and (5) annual reference-period (calendar vs fiscal). The impact of different factors was assessed using linear-regression. The calculated 30-day readmission rate for HF varied more than 2-fold depending solely on the methodological approach (6.5% to 15.0%). All-cause admission rates exhibited similar variation (18.8% to 29.9%). The highest rates included all consecutive index admissions (HF 11.1-15.0%, all-cause 24.0-29.9%), and lowest only one index admission per patient per year (HF 6.5-11.3%, all-cause 18.8-22.7%). When including multiple index admissions and compared to blanking the 30-days post-discharge, not blanking was associated with 2.3% higher readmission rates. Selecting a single admission per year with a first-in-year approach lowered readmission rates by 1.5%, while random-sampling admissions lowered estimates further by 5.2% (p<0.001). Calculated 30-day readmission rates varied more than 2-fold by altering methods. Transparent and consistent methods are needed to ensure reproducible and comparable reporting.

How different definition criteria may predict clinical outcome in treatment resistant depression: Results from a prospective real-world study

Management of treatment-resistant depression (TRD) remains a major public health challenge, also due to the lack of a consensus around TRD definition. We investigated the impact of different definitions of TRD on identifying patients with distinct features in terms of baseline characteristics, treatment strategies, and clinical outcome. We conducted a prospective naturalistic study on 538 depressed inpatients. Patients were screened for treatment resistance by two TRD definitions: looser criteria (lTRD) and stricter criteria (sTRD). We compared baseline characteristics, treatment and clinical outcome between the TRD groups and their non-TRD counterparts. 52.97 % of patients were identified as lTRD, only 28.81 % met the criteria for sTRD. sTRD patients showed lower rates of remission and slower symptom reduction compared to non-TRD patients and received more challenging treatments. Surprisingly, patients identified as sTRD also exhibited lower rates of psychiatric comorbidities, including personality disorders, substance abuse, or alcohol misuse. Stricter TRD criteria identify patients with worse clinical outcomes. Looser criteria may lead to overdiagnosis and over treatment. Clinical features known to be possible risk factors for TRD, as psychiatric comorbidities, showed to be more suggestive of a “difficult to manage” depression rather than a proper TRD.

Evaluation of Voltage Unbalance Definitions for Voltage Control in Distribution Systems with Photovoltaic Penetration

AbstractThis paper examines the impact of different voltage unbalance definitions on voltage control in unbalanced distribution systems. Traditional voltage regulation methods for unbalanced systems rely on a single voltage unbalance definition with inconsistent adoptions. In such a situation, voltage control performance can vary between definitions, and improper choice leads to control failures. In this study, we perform numerical analysis and simulations to investigate the impact of different definitions. In the numerical analysis, two definitions quantifying negative and zero sequence components are used as reference definitions, and the theoretical error range of the remaining definitions is identified. The results are further verified by the simulations on the IEEE 123 node test system with phase‐by‐phase controlled three‐phase step voltage regulators and smart photovoltaic inverters. The control of the devices is optimized to minimize or limit a specific definition. The results show that the values of each definition at the same voltage condition can differ significantly, and inappropriate definitions may lead to significant uncertainty in the voltage control. © 2024 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC.

Comparative Analysis and Definitions of Fractional Derivatives

Fractional Calculus (FC) has emerged as a valuable tool in various fields. This study explores the historical development of (FC) and examines prominent definitions regarding Fractional Derivatives (FD), such as the Riemann-Liouville, Grunwald-Letnikov, Caputo Fractional Derivative, Katugampula derivatives, Caputo Fractional Derivative, Caputo-Fabrizio Fractional Derivative and as well as Atangana-Baleanu Fractional Derivative. It critically evaluates their strengths, weaknesses and implications on (FD) equations. The findings contribute to establishing a clearer understanding of Fractional Derivatives (FD) and guiding their appropriate use in practical scenarios. It investigates the impact of different definitions on the properties and behaviors of (FD), providing valuable insights for researchers.

The impact of angles of insonation on left and right ventricular global longitudinal strain estimation in fetal speckle tracking echocardiography.

Two-dimensional speckle tracking echocardiography has been considered an angle-independent modality. However, current literature is limited and inconclusive on the actual impact of angle of insonation on strain values. Therefore, the primary objective of this study was to assess the impact of angles of insonation on the estimation of fetal left ventricular and right ventricular global longitudinal strain. Secondarily, the impact of different definitions for angles of insonation was investigated in a sensitivity analysis. This is a retrospective analysis of a prospective longitudinal cohort study with 124 healthy subjects. The analyses were based on the four-chamber view ultrasound clips taken between 18+0 and 21+6 weeks of gestation. Angles of insonation were categorized into three groups: up/down, oblique and perpendicular. The mean fetal left and right ventricular and global longitudinal strain values corresponding to these three groups were compared by an ANOVA test corrected for heteroscedasticity. Fetal left and right ventricular global longitudinal strain values were not statistically different between the three angles of insonation (p-value >0.062 and >0.149, respectively). When applying another definition for angles of insonation in the sensitivity analysis, the mean left ventricular global longitudinal strain value was significantly decreased for the oblique compared to the up/down angle of insonation (p-value 0.041). There is no evidence of a difference in fetal left and right ventricular global longitudinal strain between the different angles of insonation in fetal two-dimensional speckle tracking echocardiography.

Classification of blood pressure during sleep impacts designation of nocturnal nondipping.

The identification of nocturnal nondipping blood pressure (< 10% drop in mean systolic blood pressure from awake to sleep periods), as captured by ambulatory blood pressure monitoring, is a valuable element of risk prediction for cardiovascular disease, independent of daytime or clinic blood pressure measurements. However, capturing measurements, including determination of wake/sleep periods, is challenging. Accordingly, we sought to evaluate the impact of different definitions and algorithms for defining sleep onset on the classification of nocturnal nondipping. Using approaches based upon participant self-reports, applied definition of a common sleep period (12 am -6 am), manual actigraphy, and automated actigraphy we identified changes to the classification of nocturnal nondipping, and conducted a secondary analysis on the potential impact of an ambulatory blood pressure monitor on sleep. Among 61 participants in the Eastern Caribbean Health Outcomes Research Network hypertension study with complete ambulatory blood pressure monitor and sleep data, the concordance for nocturnal nondipping across methods was 0.54 by Fleiss' Kappa (depending on the method, 36 to 51 participants classified as having nocturnal nondipping). Sleep quality for participants with dipping versus nondipping was significantly different for total sleep length when wearing the ambulatory blood pressure monitor (shorter sleep duration) versus not (longer sleep duration), although there were no differences in sleep efficiency or disturbances. These findings indicate that consideration of sleep time measurements is critical for interpreting ambulatory blood pressure. As technology advances to detect blood pressure and sleep patterns, further investigation is needed to determine which method should be used for diagnosis, treatment, and future cardiovascular risk.

Diagnostic outcomes of robotic-assisted bronchoscopy for pulmonary lesions in a real-world multicenter community setting

BackgroundRobot-assisted bronchoscopy (RAB) is among the newest bronchoscopic technologies, allowing improved visualization and access for small and hard-to-reach nodules. RAB studies have primarily been conducted at academic centers, limiting the generalizability of results to the broader real-world setting, while variability in diagnostic yield definitions has impaired the validity of cross-study comparisons. The objective of this study was to determine the diagnostic yield and sensitivity for malignancy of RAB in patients with pulmonary lesions in a community setting and explore the impact of different definitions on diagnostic yield estimates.MethodsData were collected retrospectively from medical records of patients ≥ 21 years who underwent bronchoscopy with the Monarch® Platform (Auris Health, Inc., Redwood City, CA) for biopsy of pulmonary lesions at three US community hospitals between January 2019 and March 2020. Diagnostic yield was calculated at the index RAB and using 12-month follow-up data. At index, all malignant and benign (specific and non-specific) diagnoses were considered diagnostic. After 12 months, benign non-specific cases were considered diagnostic only when follow-up data corroborated the benign result. An alternative definition at index classified benign non-specific results as non-diagnostic, while an alternative 12-month definition categorized index non-diagnostic cases as diagnostic if no malignancy was diagnosed during follow-up.ResultsThe study included 264 patients. Median lesion size was 19.3 mm, 58.9% were peripherally located, and 30.1% had a bronchus sign. Samples were obtained via Monarch in 99.6% of patients. Pathology led to a malignant diagnosis in 115 patients (43.6%), a benign diagnosis in 110 (41.7%), and 39 (14.8%) non-diagnostic cases. Index diagnostic yield was 85.2% (95% CI: [80.9%, 89.5%]) and the 12-month diagnostic yield was 79.4% (95% CI: [74.4%, 84.3%]). Alternative definitions resulted in diagnostic yield estimates of 58.7% (95% CI: [52.8%, 64.7%]) at index and 89.0% (95% CI: [85.1%, 92.8%]) at 12 months. Sensitivity for malignancy was 79.3% (95% CI: [72.7%, 85.9%]) and cancer prevalence was 58.0% after 12 months.ConclusionsRAB demonstrated a high diagnostic yield in the largest study to date, despite representing a real-world community population with a relatively low prevalence of cancer. Alternative definitions had a considerable impact on diagnostic yield estimates.

The clinical value of metabolic syndrome and its components with respect to sudden cardiac death using different definitions: Two decades of follow-up from the Tehran Lipid and Glucose Study

BackgroundTo evaluate the impact of different definitions of metabolic syndrome (MetS) and their components on the risk of sudden cardiac death (SCD) among the Iranian population according to the World Health Organization (WHO), International Diabetes Federation (IDF), Adult Treatment Panel III (ATP III), and Joint Interim Statement (JIS) criteria.MethodsThe study population included a total of 5,079 participants (2,785 women) aged ≥ 40 years, free of cardiovascular disease (CVD) at baseline. Participants were followed for incident SCD annually up to 20 March 2018. Multivariable Cox proportional hazards regression models were applied to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs) of MetS and its components for incident SCD.ResultsThe prevalence of MetS ranged from 27.16% to 50.81%, depending on the criteria used. Over a median of 17.9 years of follow-up, 182 SCD events occurred. The WHO, IDF, and JIS definitions were strong predictors of SCD with multivariable-adjusted HRs (95% CI) of 1.68 (1.20–2.35), 1.51 (1.12–2.03), and 1.47 (1.08–1.98), respectively; these associations significantly attenuated after further adjustment for MetS components. MetS by the ATP III definition was not associated with the risk of SCD after controlling for antihypertensive, glucose-lowering, and lipid-lowering medication use. Among the components of MetS, high blood pressure (WHO definition), high waist circumference (using the national cutoff of ≥ 95 cm), and high glucose component by the JIS/IDF definitions remained independent predictors of SCD with HRs of 1.79 (1.29–2.48), 1.46 (1.07–2.00), and 1.52 (1.12–2.05), respectively.ConclusionsThe constellation of MetS, except for when defined with ATP III definition, is a marker for identifying individuals at higher risk for SCD; however, not independent of its components. Among MetS components, abdominal obesity using the population-specific cutoff point, high glucose component (JIS/IDF definitions), and high blood pressure (WHO definition) were independent predictors of SCD.

Remission and low disease activity (LDA) prevent damage accrual in patients with systemic lupus erythematosus: results from the Systemic Lupus International Collaborating Clinics (SLICC) inception cohort

ObjectiveTo determine the independent impact of different definitions of remission and low disease activity (LDA) on damage accrual.MethodsPatients with ≥2 annual assessments from a longitudinal multinational inception lupus cohort were...

P-406 Ongoing pregnancy rates (OPRs) after warmed blastocyst transfer (WBT) in a true-natural cycle (t-NC) are similar using six different luteinizing hormone (LH) surge criteria

Abstract Study question Does timing of WBT in t-NC differ according to six different commonly definitions for LH surge, and if so, do differences in timing impact OPRs? Summary answer Performing WBT on follicular collapse+5 days is equivalent to LH surge +7/+8 /+9 days in terms of OPRs, using six different definitions of LH surge. What is known already Pinpointing the day of ovulation, usually by documentation of the LH surge, and less commonly by transvaginal-ultrasonography is crucial for timing WBT in t-NC to maximize reproductive success. However, there is no consensus on the definition of the LH surge, and the most commonly used six LH-surge definitions are LH ≥ 10, ≥15, ≥17, ≥20 IU/L, ≥1.8-fold, and ≥2-fold increase from baseline. The usual practice is to schedule warmed blastocyst transfer on LH-surge +6 days. Study design, size, duration Prospective monitoring of 115 WBT cycles performed during January 2017-October 2021. The goals of the study were i)to assess how frequently and to what extent there would be a change in WBT related to the day of the LH surge, using the six different definitions of LH surge, compared to follicular collapse +5 days; ii)for each definition of the LH surge to compare OPRs of different WBT timings related to the day of LH surge. Participants/materials, setting, methods Staying locally and having regular menstrual cycles were the main criteria to perform t-NC. For t-NC, serial serum endocrine (LH, estradiol, and progesterone) and transvaginal ultrasonographic monitoring started on cycle days 8-10. Following precise documentation of follicular collapse by ultrasound, WBT was performed on follicular collapse +5 days. All included cycles were t-NC without human chorionic gonadotropin trigger or luteal phase support administration. Main results and the role of chance A total of 115 t-NC cycles were included for the first part of the study, determining the impact of different definitions of the LH-surge for the day of WBT. Our reference timing of follicular collapse +5 days would be equivalent to LH-surge +6 days in only 5.2%-41.2% of the cycles employing the six different LH-surge definitions. In contrast, the reference timing was comparable to LH surge +7 days in the majority of cycles (46.1%-70.8%) and less commonly to LH-surge +8 days (1.8%-38.3%) and +9 days (0%-10.4%). For the second part of the study, a total of 94 cycles were analyzed; 15 cycles were excluded as these cycles constituted 2nd or 3rd t-NC cycles; four cycles due to low serum progesterone (&amp;lt;7 ng/ml) on WBT-1 day and two cycles due to failure of survival after warming. For each LH-surge definition, OPRs were comparable among the different WBT timings related to the LH-surge (+6/+7/+8/+9 days). When logistic regression analysis was performed, taking LH-surge + 6 days as the reference, a change in timing was not an independent predictor of OPR for all six different definitions of the LH-surge. Limitations, reasons for caution Assignment of WBT timings related to LH-surge by our standard policy (follicular collapse +5 days), rather than by randomization, is a limitation. Other limitations include single daily measurements of serum LH and limited sample size. Wider implications of the findings Differences in warmed blastocyst timing related to the LH surge (LH surge +6/+7/+8/+9) are associated with comparable reproductive outcomes in t-NC, reflecting the flexibility of the window of implantation. Further, trials are warranted to delineate the best tool and timing of FET for warmed blastocyst transfer in t-NC. Trial registration number Not applicable

Prevalence of unruptured intracranial aneurysms: impact of different definitions – the Tromsø Study

BackgroundManagement of incidental unruptured intracranial aneurysms (UIAs) remains challenging and depends on their risk of rupture, estimated from the assumed prevalence of aneurysms and the incidence of aneurysmal subarachnoid haemorrhage....

Temporal trends in myocardial infarction case fatality: methodological challenges and prevention targets

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Health and Medical Research Council of AustraliaHealy Medical Research Foundation Background Case fatality is an important indicator of severity and quality of care for myocardial infarction (MI). Most studies focus on hospitalised case fatality, which does not capture the total burden of MI deaths. Additionally, changes in diagnostic criteria and acute clinical care, and evidence that identifying all coronary heart disease (CHD) events better captures this patient group,1 have led to suggestions that a different definition of case fatality is required. Purpose The aim of the study was to determine the impact of different definitions of case fatality on the composition of fatal cases, and to measure trends in case fatality across a range of case definitions. Methods A whole-state linked hospital/death dataset was used to identify all MI, acute coronary syndromes (ACS) and CHD events (fatal + nonfatal) from 1997-2015. The traditional MI case fatality definition included all MI deaths as the numerator, stratified as MI hospitalisation with death ≤28 days, non-MI hospitalisation with MI death ≤28 days, or pre-hospital MI deaths. The denominator was all MIs (fatal plus nonfatal MI). ACS and a broader CHD definition were trialled, with ACS or CHD deaths as the numerator respectively, stratified in a similar manner as MI. Case fatality was age-standardised by 5-year age group using the internal age distribution of each definition as the standard. Results From 1997 to 2015, there were 76,928 MI events, 126,470 ACS events, and 235,100 CHD events. Of the MI cohort, 64.1% were men, and 13.0% had a prior MI, with a similar pattern in the ACS and CHD cohorts. For the traditional definition of MI case fatality, 10,819 deaths (53.9%) occurred pre-hospital, 4990 deaths in those hospitalised for MI and dying ≤28 days (24.8%), and 4271 MI deaths (21.3%) ≤28 days of a non-MI hospitalisation (Figure). Using the broadest CHD definition of case fatality, there was a similar proportion of pre-hospital deaths, but a higher proportion of CHD deaths in those with a non-CHD hospitalisation. In men, age-standardised MI case fatality declined from 40.0% in 1997 to 17.3% by 2015; in women, the decline was from 41.9% to 18.2%. In contrast, using the ACS and broad CHD definitions, age-standardised case fatality was lower than for MI throughout the study period, with a smaller temporal decline (ACS: men 22.2% to 13.1%, women 20.5% to 13.0%; CHD: men 20.6% to 12.4%, women 19.3% to 12.3%). Conclusion Despite substantial falls in MI case fatality, the fatal burden remains high. Regardless of the case fatality definition, pre-hospital deaths from acute or all CHD have remained high over time, highlighting the need to target the pre-hospital setting. Caution is needed when using different definitions of case fatality to ensure relevant statistics are used, particularly for temporal trends. Figure Legend. Proportion of MI deaths occurring ≤28 days after MI hospitalisation (2), ≤28 days after non-MI hospitalisation (3), and pre-hospital (4).

Rehabilitation utilization of non-migrant and migrant persons with back pain: A cohort study using different definitions of migrant background

SummaryBackgroundMedical rehabilitation (MR) by the German Pension Insurance is approved to maintain and to restore work ability and to avoid disability pensions. Studies on the rehabilitation utilization by people with a migration background (PMB) compared to people without a migration background (non-PMB) showed heterogeneous results, which may be partly due to different definitions of migration status. The aim of this paper was to test whether there are differences in utilization of MR between employed PMB and non-PMB with self-reported back pain.MethodsWe used data from a large German cohort study that analyzed the effectiveness of MR for individuals with back pain and was conducted between 1st January 2017 and 31st December 2019. Employees aged 45 to 59 years who reported back pain in the last three months completed the baseline questionnaire in 2017. We used four definitions of migration background (MB) to differentiate by first- and second-generation migration, by one- and two-sided migration background, by language, or by nationality. Data on rehabilitation utilization was extracted from administrative records covering the period until the end of 2018.FindingsData of 6,713 participants were included, and 514 individuals utilized MR during follow-up. Adjusted analyses showed a decreased risk of rehabilitation utilization in people with a first-generation MB (HR = 0·46; 95% CI 0·29; 0·72), people with a two-sided MB (HR = 0·47; 95% CI 0·31; 0·72), people whose native language was not German (HR = 0·52; 95% CI 0·30; 0·91), and people without German nationality (HR = 0·29; 95% CI 0·12; 0·72) when compared to non-PMB.InterpretationThis study showed that employees with a MB reporting back pain had a significantly reduced risk for utilization of rehabilitation services. This underutilization could be observed considering different definitions of MB. Future research on rehabilitation utilization by PMB should consider the impact of different definitions on the results.FundingThe study was funded by the 10.13039/501100001659German Research Foundation (grant numbers: BE 5885/2–1; MA 6981/2–1). The German Research Foundation functions as a self-governing institution for the promotion of science and research in Germany.

Long-Term Outcomes of Persistent Post-Operative Opioid Use: A Retrospective Cohort Study.

To determine the association between persistent post-operative opioid use and the long-term risk of opioid use disorder and opioid overdose. Persistent post-operative opioid use is a commonly used outcome in the surgical literature; its incidence and risk factors have been well described. However, its association to long term outcomes, including opioid use disorder and opioid overdose, is unknown. A retrospective cohort study utilizing the Veterans Health Administration corporate data warehouse. Patients undergoing any surgery between January 1st 2008 and December 31st 2018 were included and followed until December 31st 2020. Univariate and multivariate survival analysis were used to determine the association between persistent post-operative opioid use and opioid use disorder and overdose. Sensitivity analyses were conducted to determine the impact of different definitions of persistent opioid use and the effect of pre-operative opioid use. 304,780 patients undergoing surgery were included and followed for a median of 5.56 years (IQR 3.08-8.65). Persistent post-operative opioid use was associated with an increased hazard of developing both opioid use disorder (HR = 1.88, CI: 1.80-1.96, p < 0.001) and overdose (HR = 1.78, CI: 1.67-1.90, p < 0.001). This association remained consistent after adjustment for comorbidities and across all sensitivity analyses. Surgical patients who develop persistent post-operative opioid use are at increased risk of both opioid use disorder and overdose as compared to surgical patients who do not develop persistent use.

Evaluation of different late left ventricular remodeling definitions for predicting long-term outcomes in acute myocardial infarction patients undergoing percutaneous coronary intervention

Abstract Background Late left ventricular remodeling (LLVR) after the index acute myocardial infarction (AMI) is a common complication, and is associated with poor outcome. However, the optimal definition of LLVR has been debated because of its different incidence and influence on prognosis. At present, there are limited data regarding the influence of different LLVR definitions on long-term outcomes in AMI patients undergoing percutaneous coronary intervention (PCI). Purpose To explore the impact of different definitions of LLVR on long-term mortality, re-hospitalization or an urgent visit for heart failure, and identify which definition was more suitable for predicting long-term outcomes in AMI patients undergoing PCI. Methods We prospectively observed 460 consenting first-time AMI patients undergoing PCI from January 2012 to December 2018. LLVR was defined as a ≥20% increase in left ventricular end-diastolic volume (LVEDV), or a &amp;gt;15% increase in left ventricular end-systolic volume (LVESV) from the initial presentation to the 3–12 months follow-up, or left ventricular ejection fraction (LVEF) &amp;lt;50% at follow up. These parameters of the cardiac structure and function were measuring through the thoracic echocardiography. The association of LLVR with long-term prognosis was investigated by Cox regression analysis. Results The incidence rate of LLVR was 38.1% (n=171). The occurrence of LLVR according to LVESV, LVEDV and LVEF definition were 26.6% (n=117), 31.9% (n=142) and 11.5% (n=51), respectively. During a median follow-up of 2 years, after adjusting other potential risk factors, multivariable Cox regression analysis revealed LLVR of LVESV definition [hazard ratio (HR): 2.50, 95% confidence interval (CI): 1.19–5.22, P=0.015], LLVR of LVEF definition (HR: 16.46, 95% CI: 6.96–38.92, P&amp;lt;0.001) and LLVR of Mix definition (HR: 5.86, 95% CI: 2.45–14.04, P&amp;lt;0.001) were risk factors for long-term mortality, re-hospitalization or an urgent visit for heart failure. But only LLVR of LVEF definition was a risk predictor for long-term mortality (HR: 6.84, 95% CI: 1.98–23.65, P=0.002). Conclusions LLVR defined by LVESV or LVEF may be more suitable for predicting long-term mortality, re-hospitalization or an urgent visit for heart failure in AMI patients undergoing PCI. However, only LLVR defined by LVEF could be used for predicting long-term mortality. Funding Acknowledgement Type of funding sources: None. Association Between LLVR and outcomesKaplan-Meier Estimates of the Mortality

Frequency and clinical impact of different definitions of moderate aortic stenosis

Abstract Background Current echocardiographic guidelines recommend five parameters to define severity of aortic stenosis (AS): peak velocity (PV), mean gradient (MG), aortic valve area (AVA), index AVA (AVAi), and dimensionless index (DI). However, the clinical utility of these parameters for patients with moderate AS largely remain unknown. Objective To investigate the clinical profiles and outcomes of patients with moderate AS according to five different definitions for severity. Methods Using standard echocardiographic definitions, we identified patients with moderate AS who were evaluated in our health care system from 2011 to 2012. Patient demographics, morbidities, and adverse events were reviewed, including death, heart failure (HF) admission, and aortic valve replacement (AVR). Results We enrolled 1,042 patients (age, 75±12 yrs; 40% women). Very few patients (4%) met all five criteria for moderate AS, while 49% had only one or two criteria met. DI was the most common parameter for defining moderate AS, employed in 93% of patients. Patients with area-based indices (i.e., AVA, AVAi, DI) had lower stroke volume index, lower mean gradients, lower peak velocities, and more morbidities in comparison to those flow-based definitions of severity (i.e., PV, MG). During a median follow-up of 5.7 years, overall survival was poor with all-cause mortality of 62.8%. Notably, there was no difference in the rates of mortality (range, 56.4 to 63.3%) or HF hospitalization (range, 28.9 to 32.2%) for groups defined by the five parameters, though patients with flow-based definitions more likely had AVR in follow-up. Conclusions Most patients with moderate AS meet the definition for severity with one or few criteria. Regardless of the method of definition for severity, a high rate of mortality and morbidity can occur in patients with moderate AS. Further study to optimize the clinical outcomes of patients with moderate AS is warranted. Funding Acknowledgement Type of funding source: Foundation. Main funding source(s): Minneapolis Heart Institute Foundation

The "Efficiency" Effect of Conceptual Referents on the Generation of Happiness: A Cross-National Analysis

This paper analyses how different definitions of happiness affect the individual assessment of subjective wellbeing. Bearing in mind the production theory, we study the impact of definitions of happiness on how efficiently a set of determinants are used and converted into happiness. From a theoretical point of view, we discuss the role of the Conceptual Referent Theory within the affective-cognitive process of personal evaluation of happiness. We use data from the Understanding High Happiness in Latin America survey (2018), which includes a sample of people from Colombia, Costa Rica, Mexico and the USA, to investigate how happiness conceptual referents influence personal assessment using Stochastic Frontier Analysis. This method permits to assess the impact of different definitions of happiness on how a set of standard drivers like income and social relations are used and converted into perceived happiness. To this end, conceptual referents for happiness are treated as (in)efficiency factors. This study shows that the concept of happiness shapes how individuals value the same inputs. “Stoicism”, “virtue” and “enjoyment” emerge as the most efficient referents. Also, we observe that cross-country differences in the level of perceived happiness are associated with differences in the prevalence of conceptual referents. In the USA, where less efficient definitions prevail, people report lower levels of happiness.

Impact of different definitions of atopic dermatitis

Impact of different definitions of atopic dermatitis

Defining constipation to estimate its prevalence in the community: results from a national survey

BackgroundDifferent definitions of constipation have been used to estimate its prevalence in the community but this creates difficulties when comparing results from various studies. This study explores the impact of different definitions on prevalence estimates in the same population and compares the performance of simple definitions with the Rome III criteria.MethodsThe prevalence of constipation in a large nationally representative sample of community-dwelling adults was estimated using five simple definitions of constipation and compared with definitions based on the Rome III criteria. The sensitivity, specificity, and positive and negative predictive values, were calculated for each definition using the Rome III criteria as the gold standards for chronic and sub-chronic constipation.ResultsPrevalence estimates for the five simple definitions ranged from 9.4 to 58.9%, while the prevalence estimates using the Rome III criteria were 24.0% (95%CI: 22.1, 25.9) for chronic constipation and 39.6% (95%CI: 37.5, 41.7) for sub-chronic constipation. None of the simple definitions were adequate compared to the Rome III criteria. Self-reported constipation over the past 12 months had the highest sensitivity (91.1%, 95%CI: 88.8, 93.4) and negative predictive value (94.5%, 95%CI: 93.1, 96.1) compared to the Rome III criteria for chronic constipation but an unacceptably low specificity (51.3%, 95%CI: 48.8, 53.8) and positive predictive value (37.1%, 95%CI: 34.4, 39.9).ConclusionsThe definition used to identify constipation within a population has a considerable impact on the prevalence estimate obtained. Simple definitions, commonly used in research, performed poorly compared with the Rome III criteria. Studies estimating population prevalence of constipation should use definitions based on the Rome criteria where possible.

Change in risk for narcolepsy over time and impact of definition of onset date following vaccination with AS03 adjuvanted pandemic A/H1N1 influenza vaccine (Pandemrix) during the 2009 H1N1 influenza pandemic.

To estimate risk for narcolepsy in defined time windows following exposure to adjuvanted A(H1N1) pandemic vaccine (Pandemrix) and impact of different definitions of index date for the narcolepsy diagnosis. Vaccine exposure in approximately 30% of the Swedish population in 2009 was linked to information on narcolepsy diagnosis retrieved from the national patient registry. Cases were verified by a systematic chart review. Poisson regression was used to compare incidence in defined time windows following vaccination. Of 266 cases of narcolepsy identified, 25% (66/266) were prevalent cases with symptom onset documented before vaccine exposure. Incident cases had a median time interval between first symptom and the date recorded in the patient registry of 64weeks (IQR 39-107) when vaccinated (N=182) and 65weeks (IQR 51-72) when unvaccinated (N=16). With first symptom defining index date, the adjusted risk for narcolepsy in younger patients was increased 14 times during the first year after vaccination, three times elevated the second year, but with no detectable increased risk more than 2years after vaccination exposure. Using the index date from the patient registry, the adjusted increase in risk was about seven times elevated for all three time intervals. The magnitude of the estimated increased risk for narcolepsy following exposure to the A(H1N1) pandemic vaccine is highly dependent on the method used to determine the index date for disease onset. The sometimes very long and potentially variable interval from first symptom to a health care registry diagnosis complicates estimations of risk.