Defining the normal QT interval in newborns: the natural history and reference values for the first 4 weeks of life

Abstract Aims Evaluation of the neonatal QT interval is important to diagnose arrhythmia syndromes and evaluate side effects of drugs. We aimed at describing the natural history of the QT interval duration during the first 4 weeks of life and to provide reference values from a large general population sample. Methods and results The Copenhagen Baby Heart Study is a prospective general population study that offered cardiac evaluation of newborns. Eight-lead electrocardiograms were obtained and analysed with a computerized algorithm with manual validation. We included 14 164 newborns (52% boys), aged 0–28 days, with normal echocardiograms. The median values (ms, 2–98%ile) for the corrected intervals QTc (Bazett), QTc (Hodges), QTc (Fridericia), and QTc (Framingham) were 419 (373–474), 419 (373–472), 364 (320–414), and 363 (327–405). During the 4 weeks, we observed a small decrease of QTcFramingham, and an increase of QTcHodges (both P < 0.01), while QTcBazett and QTcFridericia did not change (P > 0.05). Applying published QT interval cut-off values resulted in 5–25% of the newborns having QT prolongation. Uncorrected QT intervals decreased linearly with increasing heart rate (HR). Sex and infant size did not affect the QT interval and the gestational age (GA) only showed an effect when comparing the extreme low- vs. high GA groups (≤34 vs. ≥42 weeks, P = 0.021). Conclusion During the 4 weeks QTcFramingham and QTcHodges showed minor changes, whereas QTcBazett and QTcFridericia were stable. The QT interval was unaffected by sex and infant size and GA only showed an effect in very premature newborns. Reference values for HR-specific uncorrected QT intervals may facilitate a more accurate diagnosis of newborns with abnormal QT intervals.

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The Evolution of the Neonatal QRS Axis during the First Four Weeks of Life

Neonatology ◽

10.1159/000513526 ◽

2021 ◽

pp. 1-8

Author(s):

Maria Munk Pærregaard ◽

Jesper Kock ◽

Christian Pihl ◽

Adrian Pietersen ◽

Kasper Karmark Iversen ◽

...

Keyword(s):

Heart Disease ◽

General Population ◽

Early Diagnosis ◽

Population Study ◽

Reference Values ◽

Gestational Age ◽

General Population Study ◽

Heart Study ◽

Cardiac Evaluation ◽

Ventricular Depolarization

Background: The QRS axis represents the sum and orientation of the ventricular depolarization. Accurate interpretation of abnormalities in the QRS axis may facilitate early diagnosis of heart disease in newborns. We aimed at describing the evolution of the QRS axis during the first 4 weeks of life and provide reference values from healthy newborns. Methods: The Copenhagen Baby Heart Study is a prospective general population study that offered cardiac evaluation during the first month of life to all newborns delivered in the Copenhagen area. Results: Electrocardiograms from 12,317 newborns (52% boys; mean age 12 days) with normal echocardiograms were included. The median QRS axis was 119° at the ages 0–7 days and shifted leftward to 102° at the ages 22–28 days (p < 0.001). We found that girls had a significantly less pronounced right-shifted axis than boys (p < 0.001) and that increasing gestational age (GA) was associated with a more pronounced right-shifted axis (p < 0.05). Infant size did not affect the axis (p > 0.05). Only 0.5% had an axis within the interval 0 to −90° and 1.1% in the interval +240 to +30°. Conclusions: The QRS axis showed a gradual leftward-shift during the first 4 weeks of life and was affected by sex and GA but unaffected by infant size. Less than 1% of the newborns had a QRS axis between 0 and −90°. This study represents updated reference values, which may facilitate the clinical handling of newborns.

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The natural history of drug use from adolescence to the mid-thirties in a general population sample.

American Journal of Public Health ◽

10.2105/ajph.85.1.41 ◽

1995 ◽

Vol 85 (1) ◽

pp. 41-47 ◽

Cited By ~ 574

Author(s):

K Chen ◽

D B Kandel

Keyword(s):

Drug Use ◽

General Population ◽

Natural History ◽

Population Sample ◽

General Population Sample ◽

History Of

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Gestational Age and Neonatal Electrocardiograms

PEDIATRICS ◽

10.1542/peds.2021-050942 ◽

2021 ◽

Author(s):

Joachim Hartmann ◽

Maria Munk Pærregaard ◽

Jakob Norsk ◽

Adrian Pietersen ◽

Kasper Karmark Iversen ◽

...

Keyword(s):

Reference Values ◽

Gestational Age ◽

Cardiac Conduction ◽

Specific Reference ◽

General Population Study ◽

Heart Study ◽

Cardiac Evaluation ◽

Almost All ◽

Electrocardiogram Ecg ◽

The Impact

OBJECTIVES Interpretation of the neonatal electrocardiogram (ECG) is challenging due to the profound changes of the cardiovascular system in this period. We aimed to investigate the impact of gestational age (GA) on the neonatal ECG and create GA-specific reference values. METHODS The Copenhagen Baby Heart Study is a prospective general population study that offered cardiac evaluation of neonates. ECGs and echocardiograms were obtained and systematically analyzed. GA, weight, height, and other baseline variables were registered. RESULTS We included 16 462 neonates (52% boys) with normal echocardiograms. The median postnatal age was 11 days (range 0 to 30), and the median GA was 281 days (range 238 to 301). Analyzing the ECG parameters as a function of GA, we found an effect of GA on almost all investigated ECG parameters. The largest percentual effect of GA was on heart rate (HR; 147 vs 139 beats per minute), the QRS axis (103° vs 116°), and maximum R-wave amplitude in V1 (R-V1; 0.97 vs 1.19 mV) for GA ≤35 vs ≥42 weeks, respectively. Boys had longer PR and QRS intervals and a more right-shifted QRS axis within multiple GA intervals (all P < .01). The effect of GA generally persisted after multifactorial adjustment. CONCLUSIONS GA was associated with significant differences in multiple neonatal ECG parameters. The association generally persisted after multifactorial adjustment, indicating a direct effect of GA on the developing neonatal cardiac conduction system. For HR, the QRS axis, and R-V1, the use of GA-specific reference values may optimize clinical handling of neonates.

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Low-Grade Inflammation in the Association between Mild-to-Moderate Hypertriglyceridemia and Risk of Acute Pancreatitis: A Study of More Than 115000 Individuals from the General Population

Clinical Chemistry ◽

10.1373/clinchem.2018.294926 ◽

2019 ◽

Vol 65 (2) ◽

pp. 321-332 ◽

Cited By ~ 19

Author(s):

Signe E J Hansen ◽

Christian M Madsen ◽

Anette Varbo ◽

Børge G Nordestgaard

Keyword(s):

Acute Pancreatitis ◽

General Population ◽

Low Grade ◽

General Population Study ◽

Reactive Protein ◽

Hazard Ratios ◽

Heart Study ◽

Blood Leukocyte ◽

Low Grade Inflammation ◽

Multivariable Adjustment

Abstract BACKGROUND How mild-to-moderate hypertriglyceridemia (2–10 mmol/L; 177–886 mg/dL) potentially causes acute pancreatitis is unknown; however, cellular studies indicate that inflammation might be a driver of disease progression. We tested the hypotheses that (a) mild-to-moderate hypertriglyceridemia is associated with low-grade inflammation and that (b) the association between mild-to-moderate hypertriglyceridemia and risk of acute pancreatitis depends on low-grade inflammation. METHODS From the Copenhagen General Population Study and the Copenhagen City Heart Study, 117865 men and women 20–100+ years of age with measurements of nonfasting plasma triglycerides at baseline were followed prospectively for development of acute pancreatitis. RESULTS After multivariable adjustment, a 1 mmol/L (89 mg/dL) higher nonfasting triglyceride concentration was associated with 17% (95% CI, 16%–18%, P = 3 × 10−17) higher plasma C-reactive protein (CRP) and a 4.2% (4.0%–4.4%, P = 6 × 10−17) higher blood leukocyte count. Higher concentrations of nonfasting triglycerides were associated almost linearly with higher risk of acute pancreatitis (P for trend = 5 × 10−6), with hazard ratios of 1.5 (95% CI, 0.9–2.5), 2.0 (95% CI, 1.1–3.6), 2.2 (95% CI, 1.0–4.7), 4.2 (95% CI, 1.6–11.5), and 7.7 (95% CI, 3.0–19.8) in individuals with nonfasting triglycerides of 1.00–1.99 mmol/L (89–176 mg/dL; 46% of the population), 2.00–2.99 mmol/L (177–265 mg/dL; 17%), 3.00–3.99 mmol/L (266–353 mg/dL; 6%), 4.00–4.99 mmol/L (354–442 mg/dL; 2%), and ≥5mmol/L(443 mg/dL; 2%), respectively, vs individuals with <1 mmol/L (89 mg/dL; 27%). The association with risk of acute pancreatitis appeared more pronounced in individuals with CRP of ≥1.39 mg/L (P for trend = 0.001) and leukocytes of ≥7 × 109/L (P = 2 × 10−4) than in those with CRP <1.39 mg/L (P = 0.03) and leukocytes <7 × 109/L (P = 0.04); however, there was no formal evidence of statistical interaction (P = 0.38 for CRP and P = 0.41 for leukocytes). CONCLUSIONS Mild-to-moderate hypertriglyceridemia is associated with low-grade inflammation and higher risk of acute pancreatitis. The association between mild-to-moderate hypertriglyceridemia and risk of acute pancreatitis is possibly partly mediated by low-grade inflammation.

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Association between posttraumatic stress and acceptance of social changes: Findings from a general population study and proposal of a new concept

International Journal of Social Psychiatry ◽

10.1177/0020764016687788 ◽

2017 ◽

Vol 63 (2) ◽

pp. 126-131 ◽

Cited By ~ 5

Author(s):

Evaldas Kazlauskas ◽

Paulina Zelviene

Keyword(s):

Posttraumatic Stress Disorder ◽

General Population ◽

Posttraumatic Stress ◽

Social Factors ◽

Stress Disorder ◽

Population Sample ◽

Social Changes ◽

Event Scale ◽

General Population Study ◽

The Impact

Background: There is a growing understanding of the importance of the social factors of posttraumatic stress disorder. Aims: This study expands research on association between posttraumatic stress and social factors by introducing the measure of the acceptance of social changes and evaluating possible links between posttraumatic stress disorder symptoms and acceptance of social changes. Methods: A general population sample ( n = 778) aged from 18 to 89 years ( M = 40.2) from Lithuania participated in our study, of whom 68% reported exposure to traumatic events. Posttraumatic stress reactions were measured with the Impact of Event Scale – Revised (IES-R), and acceptance of social changes was measured with the Acceptance of Social Changes Instrument (SOCHI) developed by the authors of this study. Results: About 8% of the participants had a potential posttraumatic stress disorder (PTSD) diagnosis. Acceptance of social changes was negatively associated with posttraumatic stress. PTSD was related to lower acceptance of social changes ( d = .61). Structural equation model (SEM) revealed the mediating role of PTSD for acceptance of social changes following trauma exposure. Conclusion: Findings of our study indicate that the acceptance of social changes might be an important psychosocial factor of PTSD.

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Characteristics and Prognosis for Women with Hypertension in a Community: Results of a Longitudinal Study in Göteborg, Sweden

Clinical Science ◽

10.1042/cs051649s ◽

1976 ◽

Vol 51 (s3) ◽

pp. 649s-651s

Author(s):

C. Bengtsson ◽

O. Lindquist

Keyword(s):

Myocardial Infarction ◽

Longitudinal Study ◽

General Population ◽

Population Study ◽

Death Rate ◽

Population Sample ◽

Left Ventricular ◽

Ecg Changes ◽

Left Ventricular Strain ◽

History Of

1. During the years 1968–69 a population study of 1462 women aged 38–60 years was carried out in Göteborg, Sweden. A total of 126 women were classified as hypertensive. 2. Hypertensive women reported a history of albuminuria and hypertension during pregnancy more often than women in the general population. Albuminuria, alterations of the eye-ground vessels and ECG changes indicating left ventricular strain were more often found in hypertensive women. Hypertensive women were on average heavier. 3. The same population sample was re-studied 6 years later. Two of the 126 women classified as hypertensive had died during the 6 years interval since the first examination, both from myocardial infarction. The death rate was similar to the population sample as a whole.

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Prevalence of Light-Chain Monoclonal Gammopathy of Undetermined Significance (LC-MGUS) among Olmsted County, Minnesota Residents Aged 50 Years or Greater.

Blood ◽

10.1182/blood.v108.11.5060.5060 ◽

2006 ◽

Vol 108 (11) ◽

pp. 5060-5060

Author(s):

S. Vincent Rajkumar ◽

Robert Kyle ◽

Matthew Plevak ◽

Raynell Clark ◽

Dirk Larson ◽

...

Keyword(s):

Multiple Myeloma ◽

General Population ◽

Natural History ◽

Light Chain ◽

Monoclonal Gammopathy ◽

Olmsted County ◽

Serum Samples ◽

Geographic Population ◽

History Of ◽

Undetermined Significance

Abstract Background: Monoclonal gammopathy of undetermined significance (MGUS) is a premalignant plasma cell disorder that carries a 1% per year risk of progression to multiple myeloma (MM) or related malignancy. The prevalence and natural history of MGUS, in which by definition intact immunoglobulin heavy chain (IgH) is expressed, has been well described. However, up to 20% of myeloma (MM) is characterized by complete lack of IgH expression (Light-chain MM); the prevalence of a corresponding precursor entity, light chain MGUS (LC-MGUS) has not been determined. We report the first prevalence estimates of LC-MGUS in the general population from a large, well-defined geographic population using modern laboratory techniques. Methods: The cohort for this study was derived from one previously assembled by us to estimate the prevalence of MGUS (N Engl J Med2006;354:1362-9). The original cohort used to estimate the prevalence of MGUS consisted of 21,463 of the 28,038 enumerated residents aged 50 or over of Olmsted County Minnesota as of January 1, 1995. The sensitive serum free light chain (FLC) assay (The Binding Site Limited, Birmingham, U.K.) was performed on stored serum samples from these 21,463 persons. IgH expression was determined by immunofixation on all FLC results that had an abnormal kappa/lambda ratio (<0.26 or >1.65). LC-MGUS was defined as the presence of an abnormal FLC ratio and a negative immunofixation for IgH expression. Results: Adequate stored serum samples were available in 20,733 (97%) of the 21,463 persons. To date, the FLC assay has been performed and results were available for analysis on samples from 16,637 persons. An abnormal FLC ratio was observed in 572 persons. IgH expression was detected in 255 of these cases on immunofixation; these persons are considered as having MGUS, and were excluded from the estimation of LC-MGUS prevalence. This resulted in 317 persons out of 16,637 who had an abnormal FLC ratio without evidence of IgH expression, resulting in an estimated prevalence of LC- MGUS of 2%. Of the 317 cases of LC-MGUS identified in this study, 217 were kappa and 100 were lambda; in 35 cases the presence of the corresponding monoclonal light chain was apparent on immunofixation. The median age of the cohort of LC-MGUS was 62 years; males=151, females =166. The involved FLC level ranged from 0.118–270.0 mg/dL. The FLC ratio ranged from 0.014–0.253 (lambda) and 1.67–511.01 (kappa). So far, progression to multiple myeloma has occurred in 4 patients, a rate much higher than what is expected based on the prevalence of myeloma in the general population. Two additional patients have developed CLL. Conclusions: LC-MGUS is prevalent in 2% of the general population aged 50 years of age or older. The natural history of this disorder needs to be determined.

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WHAT IS THE NATURAL HISTORY OF GASTROESOPHAGEAL REFLUX DISEASE, DYSPEPSIA, AND IRRITABLE BOWEL SYNDROME IN THE GENERAL POPULATION?

Evidence-Based Gastroenterology ◽

10.1097/00132579-200111000-00005 ◽

2001 ◽

Vol 2 (4) ◽

pp. 141-142

Author(s):

George N. Ioannou ◽

Jason A. Dominitz

Keyword(s):

Irritable Bowel Syndrome ◽

Gastroesophageal Reflux Disease ◽

General Population ◽

Natural History ◽

Gastroesophageal Reflux ◽

Reflux Disease ◽

History Of ◽

Irritable Bowel

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Feasibility of evaluation of the natural history of kidney disease in the general population using electronic healthcare records

Clinical Kidney Journal ◽

10.1093/ckj/sfaa175 ◽

2020 ◽

Author(s):

Faye Cleary ◽

David Prieto-Merino ◽

Sally Hull ◽

Ben Caplin ◽

Dorothea Nitsch

Keyword(s):

Chronic Kidney Disease ◽

Kidney Disease ◽

General Population ◽

Natural History ◽

Sufficient Information ◽

Long Term Changes ◽

History Of ◽

Method Of Evaluation ◽

Changes Over Time

Abstract Background Knowledge about the nature of long-term changes in kidney function in the general population is sparse. We aim to identify whether primary care electronic healthcare records capture sufficient information to study the natural history of kidney disease. Methods The National Chronic Kidney Disease Audit database covers ∼14% of the population of England and Wales. Availability of repeat serum creatinine tests was evaluated by risk factors for chronic kidney disease (CKD) and individual changes over time in estimated glomerular filtration rate (eGFR) were estimated using linear regression. Sensitivity of estimation to method of evaluation of eGFR compared laboratory-reported eGFR and recalculated eGFR (using laboratory-reported creatinine), to uncover any impact of historical creatinine calibration issues on slope estimation. Results Twenty-five per cent of all adults, 92% of diabetics and 96% of those with confirmed CKD had at least three creatinine tests, spanning a median of 5.7 years, 6.2 years and 6.1 years, respectively. Median changes in laboratory-reported eGFR (mL/min/1.73 m2/year) were −1.32 (CKD) and −0.60 (diabetes). Median changes in recalculated eGFR were −0.98 (CKD) and −0.11 (diabetes), underestimating decline. Magnitude of underestimation (and between-patient variation in magnitude) decreased with deteriorating eGFR. For CKD Stages 3, 4 and 5 (at latest eGFR), median slopes were −1.27, −2.49 and -3.87 for laboratory-reported eGFR and −0.89, −2.26 and −3.75 for recalculated eGFR. Conclusions Evaluation of long-term changes in renal function will be possible in those at greatest risk if methods are identified to overcome creatinine calibration problems. Bias will be reduced by focussing on patients with confirmed CKD.

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