Etanercept originator versus etanercept biosimilar for the treatment of rheumatoid arthritis as a first biologic: results from the BSRBR-RA

OBJECTIVES

Etanercept biosimilars show comparable efficacy to their originators among biologic-naïve patients with RA in randomized controlled trials. Nationwide guidelines have obligated prescribing of etanercept biosimilars from 2016, resulting in significant cost savings. This analysis aimed to compare the effectiveness of etanercept originator vs etanercept biosimilar amongst biologic-naïve RA patients treated in routine clinical practice in the UK.

METHODS

Biologic-naïve RA patients starting etanercept in the British Society for Rheumatology Biologics Register in Rhematoid Arthritis (BSRBR-RA) cohort study from 2010 were included. Data collected at start of therapy includes patient demographics and disease activity. Follow-up data includes changes in disease activity and anti-rheumatic therapy. Six- and 12-month primary outcomes include DAS for 28-joints (DAS28) remission, EULAR response and minimal clinically important difference in function. Etanercept drug survival was assessed using Kaplan-Meier and Cox regression, including reasons for treatment withdrawal. Multiple imputation accounted for missing data. Propensity-decile adjustment was used to account for confounding by indication.

RESULTS

A total of 1806 biologic-naïve RA patients started etanercept: 1009 originator, 797 biosimilar. At 6 and 12 months, the proportion of patients achieving DAS28 remission and EULAR response were similar between treatments. During follow-up, 19% of originator patients switched onto etanercept biosimilar. Patients were censored at time of switch. Patients on originator were no more likely to stop therapy vs biosimilar; 71% of originator and 76% of biosimilar patients remained on therapy at 1 year.

CONCLUSIONS

In one of the largest analyses of patients with RA, biologic-naïve RA patients treated with etanercept originator showed similar outcomes vs biosimilar using real-world data. Drug survival, and disease activity after 6 and 12 months of therapy, was similar between cohorts.

Outcomes following switching from etanercept originator to etanercept biosimilar in 1024 RA patients: A matched-analysis of the BSRBR-RA

OBJECTIVES

Adults with RA are being switched from etanercept originator to biosimilar in non-medical/cost-saving switching. This analysis aims to investigate outcomes in these patients, including (a) drug survival and (b) disease activity at six and 12-month, compared with those who remain on originator.

METHODS

Using BSRBR-RA, those who switched directly from etanercept originator to biosimilar were identified and matched to patients receiving originator, based on gender, age, disease duration, originator start year. Drug survival was calculated; Cox-proportional hazard models assessed differences in drug persistence between those who switched versus remaining on originator. Change in DAS28 after six and 12-months was compared between cohorts. Multiple imputation was used.

RESULTS

1024 adults with RA switching from etanercept originator to biosimilar were included, with a matched cohort of patients remaining on originator. Patients who switched onto a biosimilar product were no more likely to discontinue etanercept treatment versus those who remained on originator; hazard ratio 1.06 (95%CI 0.89-1.26), with 65% of patients remaining on treatment at three years. Ninety-five (9%) patients switched back to originator within the first year. After six and 12-months, biosimilar patients were no more likely to have a worsening of DAS28 (>0.6units) compared with those who remained on originator.

CONCLUSIONS

This is the largest matched comparative effectiveness analysis showing patients switched from etanercept originator to biosimilar appear to do just as well with regards to disease activity and drug persistence compared with those who remained on originator. These data will be reassuring to clinicians and patients regarding non-medical switching.

Prevalence of Childhood Obesity in the United States in 1999-2018: A 20-Year Analysis

INTRODUCTION

Obesity is a public health crisis in the USA. This study aimed to estimate the prevalence of obesity and severe obesity in US children and adolescents and identify novel targetable risk factors associated with childhood obesity.

METHODS

From the US National Health and Nutrition Examination Survey from 1999 to 2018, 35,907 children aged 2-19 with body mass index (BMI) data were included. Obesity and severe obesity were defined as BMI ≥95th percentile and ≥120% of 95th percentile of US Centers for Disease Control and Prevention growth charts, respectively. Trends in the prevalence of obesity and subgroup analyses according to socioeconomic factors and language used in the interview were analyzed.

RESULTS

The prevalence of obesity and severe obesity increased from 14.7 [95% confidence interval: 12.9-17.0]% to 19.2 [17.2-21.0]% and 3.9 [2.9-5.0]% to 6.1 [4.8-8.0]% in 1999-2018, respectively (p = 0.001 and p = 0.014, respectively). In 2017-2018, the prevalence of obesity among children from Spanish-speaking households was 24.4 [22.4-27.0]%, higher than children from English-speaking households (p = 0.027).

CONCLUSION

The prevalence of childhood obesity kept increasing in 1999-2018. The problem is worse in children from Spanish-speaking households. Novel and targeted public health intervention strategies are urgently warranted to effectively halt the rising epidemic of childhood obesity.

Association between the liver fat score (LFS) and cardiovascular diseases in the national health and nutrition examination survey 1999-2016

BACKGROUND

The liver fat score (LFS) has been proposed to be a simple non-invasive marker of non-alcoholic fatty liver disease (NAFLD), which is highly prevalent in the general population. We tested its association with cardiovascular diseases (CVDs) and prognosis.

METHODS

17,244 adult participants from the National Health and Nutrition Examination Survey 1999-2016 were included. LFS is calculated from variables including serum aspartate transaminase/alanine transaminase (AST/ALT) ratio, fasting serum aspartate transaminase (AST) level, fasting serum insulin level, presence of metabolic syndrome and diabetes mellitus. In cross-sectional analysis, logistic regression was used to examine the association of the LFS with coronary heart disease (CHD), myocardial infarction (MI), congestive heart failure (CHF), stroke and angina pectoris. Mortality during follow-up was analysed using Cox proportional hazard regression.

RESULTS

LFS was associated with CHD (adjusted odds ratio [OR]: 1.09 per standard deviation [SD], 95% confidence interval [95% CI]: 1.03-1.15) (p = .003), CHF (1.11, 1.04-1.18) (p = .003) and angina pectoris (1.08, 1.02-1.13) (p = .005). LFS was not associated with MI or stroke, but was associated with increased all-cause and cardiovascular mortality with hazard ratios (HRs) of 1.10 (95% CI: 1.07-1.13) (p < .001) and 1.12 (95% CI: 1.06-1.17) (p < .001), respectively.

CONCLUSIONS

NAFLD is usually asymptomatic, but this large study of a large general population shows that LFS is associated with CHD, CHF, angina pectoris, cardiovascular and all-cause mortality. Determining the LFS is worthwhile, as it identifies people with NAFLD, who may also be at increased cardiovascular risk.Key MessagesLiver fat score (LFS), a non-invasive marker of non-alcoholic fatty liver disease (NAFLD), is associated with coronary heart disease (CHD), congestive heart failure (CHF) and angina.LFS is also associated with increased cardiovascular and all-cause mortality.Determining the LFS is worthwhile as it identifies people with NAFLD as well as increased cardiovascular risk.

Prevalence of metabolic syndrome in the United States National Health and Nutrition Examination Survey (nhanes) 2011–2018

Background

Metabolic syndrome (MetS) is a cluster of risk factors presaging the development of cardiovascular disease and diabetes. It is a risk factor for severe coronavirus disease 2019 (COVID-19).

Purpose

To estimate the prevalence of MetS in the US National Health and Nutrition Examination Survey (NHANES) 2011–2018.

Methods

This cohort study included 22370 eligible participants aged ≥20 years from the NHANES 2011–2018. MetS was defined as the presence of at least three of these components: central obesity, reduced high-density lipoprotein, elevated triglycerides, elevated blood pressure and elevated fasting blood glucose. The prevalence of MetS was estimated taking into account the complex sampling. The time trend was evaluated using logistic regression. Annual percentage changes (APC) were measured trend in MetS prevalence.

Results

The prevalence of MetS was 36.2% (95% CI, 32.3–40.3), 34.8% (95% CI, 32.3–37.4), 39.9% (95% CI, 36.6–43.2) and 38.3% (95% CI, 35.3–41.3) in 2011–2, 2013–4, 2015–6, 2017–8, respectively (P for trend = 0.08). Among the MetS components, the prevalence of elevated glucose increased from 48.7% (95% CI, 45.9–51.5) in 2011–2 to 64.3% (95% CI, 61.0–67.4) in 2017–8 [P for trend &lt;0.001; APC=11.7, (95% CI, 3.5–21.0)]. The prevalence of MetS in non-Hispanic Asian increased from 21.8% (95% CI, 16.7–28.0) in 2011–2 to 31.2% (95% CI, 27.4–35.3) in 2017–8 [P for trend &lt;0.001; APC=14.6, (95% CI, 2.5–34.8)].

Conclusions

The prevalence of MetS remained stable during 2011 to 2018. Lifestyle modification is needed, especially among non-Hispanic Asians to prevent the metabolic syndrome and the associated risks of diabetes and cardiovascular disease.

Funding Acknowledgement

Type of funding sources: None.

Proportion of patients taking indapamide developing severe hypokalaemia

Introduction

Diuretics are commonly used for the treatment of hypertension. Yet, hypokalaemia is a well-recognized adverse effect.

Purpose

To evaluate the proportion of patients taking indapamide who developed severe hypokalaemia, defined as requiring hospitalisation. Indapamide was by far the most commonly used diuretic for hypertension in Hong Kong.

Methods

We searched the Hong Kong Hospital Authority Clinical Data Analysis and Reporting System, which is a territory-wide database of computerised medical records. All hypertensive patients prescribed indapamide monotherapy in 2007–2016 and all admissions due to hypokalaemia in 2007–2018 were traced. Factors associated with hospitalisation were studied using multivariable logistic regression.

Results

During the study period, 62,881 patients were started on indapamide and 509 (0.81%) were hospitalised for hypokalaemia. 59% of these hospitalisations occurred within 16 weeks. Female sex (OR = 1.73; 95% CI, 1.43–2.09) and immediate-release formulation (OR = 1.44; 95% CI, 1.16–1.78) were associated with hospitalisation. In the multivariable model, advanced age was not a significant predictor. There were no deaths during hospitalisation and the median length of hospital stay was one day.

Conclusions

In this large population-based study with 147614 person-years of follow-up, severe hypokalaemia requiring hospitalisation was uncommon among hypertensive patients on indapamide. Half of these occurred during the first 16 weeks. Female sex and the immediate release formulation increased the risk. We conclude that using indapamide to treat hypertension is safe, even in the elderly, especially if the sustained release formulation is used and electrolytes are monitored periodically.

Funding Acknowledgement

Type of funding sources: None.

The seroprevalence and kinetics of IgM and IgG in the progression of COVID-19

BACKGROUND

SARS-CoV-2 is a novel coronavirus first recognized in late December 2019 that causes coronavirus disease 19 (COVID-19). Due to the highly contagious nature of SARS-CoV-2, it has developed into a global pandemic in just a few months. Antibody testing is an effective method to supplement the diagnosis of COVID-19. However, multicentre studies are lacking to support the understanding of the seroprevalence and kinetics of SARS-CoV-2 antibodies in COVID-19 epidemic regions.

METHOD

A multicentre cross-sectional study of suspected and confirmed patients from 4 epidemic cities in China and a cohort study of consecutive follow-up patients were conducted from 29/01/2020 to 12/03/2020. IgM and IgG antibodies elicited by SARS-CoV-2 were tested by a chemiluminescence assay. Clinical information, including basic demographic data, clinical classification, and time interval from onset to sampling, was collected from each centre.

RESULTS

A total of 571 patients were enrolled in the cross-sectional study, including 235 COVID-19 patients and 336 suspected patients, each with 91.9%:2.1% seroprevalence of SARS-CoV-2 IgG and 92.3%:5.4% seroprevalence of SARS-CoV-2 IgM. The seroprevalence of SARS-CoV-2 IgM and IgG in COVID-19 patients was over 70% less than 7 days after symptom onset. Thirty COVID-19 patients were enrolled in the cohort study and followed up for 20 days. The peak concentrations of IgM and IgG were reached on the 10th and 20th days, respectively, after symptom onset. The seroprevalence of COVID-19 IgG and IgM increased along with the clinical classification and treatment time delay.

CONCLUSION

We demonstrated the kinetics of IgM and IgG SARS-CoV-2 antibodies in COVID-19 patients and the association between clinical classification and antibodies, which will contribute to the interpretation of IgM and IgG SARS-CoV-2 antibody tests and in predicting the outcomes of patients with COVID-19.

Posters from the 24th Annual Scientific Meeting of the International Society of Cardiovascular Pharmacotherapy: Best Poster Award - First Prize: Network Meta-analysis to Determine the Optimal Level of Systolic Blood Pressure for Hypertensive Patients

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Prevalence of metabolic syndrome among ethnic groups in China

Background

Metabolic syndrome (MetS) is common in China, which has a multi-ethnic population of 1·3 billion. We set out to determine the prevalence of MetS and its components in different ethnic groups.

Methods

This nationwide cross-sectional survey involved 24,796 participants from eight ethnicities in six provinces in China from 2008 to 2011. MetS was defined using the modified National Cholesterol Education Program Adult Treatment Panel III criteria. Results were analysed using SPSS version 22·0 in 2018. Logistic regression was used for deriving odds ratios and 95% confidence intervals of risk factors for the MetS.

Results

The prevalence of MetS increased with age from 3·60% to 21·68%. After age standardization, the prevalence of MetS, in descending order, was 35·42% (Korean), 22·82% (Hui), 19·80% (Han), 13·72% (Miao), 12·90% (Tujia), 12·04% (Li), 11·61% (Mongolian), 6·17% (Tibetan). Korean ethnicity was associated with a higher prevalence in five components of MetS, while Tibetan ethnicity was associated with lower prevalence except decreased HDL cholesterol. Logistic regression analyses showed that age, drinking and being non-Tibetan were associated with a higher risk of MetS.

Conclusions

Within one country, albeit a large one, the prevalence of MetS can vary greatly. Chinese of Korean ethnicity had a much higher prevalence than Tibetan ethnicity. Measures to tackle MetS should be tailored to the ethnic groups within a population.

Vancomycin-associated acute kidney injury in Hong Kong in 2012-2016

Background

To study the incidence of vancomycin-associated acute kidney injury (VA-AKI) in Hong Kong and identify risk factors for VA-AKI.

Method

Patients with vancomycin prescription and blood level measurement in 2012–2016 were identified using the Hong Kong Hospital Authority Clinical Data Analysis and Reporting System. Acute kidney injury was defined using KDIGO criteria. Patients without creatinine measurements, steady-state trough vancomycin level or who had vancomycin treatment < 3 days were excluded. Results were analyzed using SPSS version 22.0. Logistic regression was used to identify the predictors for VA-AKI. Odds ratio and 95% confidence interval were estimated.

Results

One thousand four hundred fifty patients were identified as VA-AKI from 12,758 records in Hong Kong in 2012–2016. The incidence was respectively 10.6, 10.9, 11.3, 12.2, 11.2% from 2012 to 2016. The incidence of VA-AKI was 16.3, 12.2, 11.3 and 6.2% in patients aged 1–12, 12–60, elderly aged > 60 and newborn and infants, respectively. Baseline creatinine, serum trough vancomycin level, systematic disease history including respiratory failure, hypertension, congestive heart failure, chronic renal failure, anemia and type II diabetes, and concomitant diuretics, piperacillin-tazobactam (PTZ) and meropenem prescription were significantly higher in VA-AKI patients older than 12 years. Logistic regression showed that older age group, higher baseline creatinine, serum trough vancomycin level, respiratory failure, chronic renal failure and congestive heart failure, concomitant diuretics, PTZ and meropenem prescription, and longer hospital stay were all associated with increased risk of VA-AKI.

Conclusion

The incidence of VA-AKI in Hong Kong is low but shows no decline. Patients with higher baseline creatinine, multi-organ diseases and multiple drugs administration should have their vancomycin level monitored to decrease the risk of VA-AKI.

The lipid-lowering effect of once-daily soya drink fortified with phytosterols in normocholesterolaemic Chinese: a double-blind randomized controlled trial

PURPOSE

Phytosterols reduce intestinal cholesterol absorption and help to lower LDL-cholesterol. Many Chinese adults are lactose-intolerant and cannot tolerate bovine milk enriched with phytosterol. Soya-milk is a common beverage in Asia and it has beneficial effects on general health. We therefore conducted a randomized double-blind controlled trial to assess the effectiveness of a phytosterols-enriched soya drink in lowering serum LDL-cholesterol level (primary outcome) and other cardiovascular parameters (secondary outcomes).

METHODS

One hundred and fifty-nine normocholesterolaemic participants (85 men and 74 women; aged 19-79) were randomized to daily intake of one serving of phytosterols-enriched soya drink (N = 82), equivalent to 2 g of phytosterol per day, or a matched soya drink without phytosterols (N = 77) for 3 weeks. Adverse events, withdrawal and compliance were documented.

RESULTS

Among the treatment group (N = 82), phytosterols-enriched soya drink significantly decreased LDL-cholesterol by 5.96% (SE 1.48, 95% CI - 8.91%, - 3.00%) with a median of 6.74% compared with baseline, resulting in a significant reduction of 4.70% (95% CI - 8.89%, - 0.51%; p = 0.028) with a median of 5.20% compared with placebo (N = 77). In contrast, there were no significant changes in other lipid parameters, blood glucose, blood pressure, body weight or waist circumference. Remarkably, 95% of the participants randomized to the fortified drink reported no adverse events at all.

CONCLUSIONS

Daily consumption of a phytosterols-enriched soya drink may be a simple and cost-neutral means of lowering LDL-cholesterol in individuals in China, with massive population and rising incidence of coronary heart disease (ClinicalTrials.gov identifier: NCT02881658; date of registration: 14 Aug 2016).

Cardiovascular outcomes in trials of new antidiabetic drug classes: a network meta-analysis

BACKGROUND

Recent trials suggested that glucagon-like peptide-1 receptor agonists (GLP-1 RAs) and sodium-glucose co-transporter-2 (SGLT-2) inhibitors reduced cardiovascular events. Comparative effectiveness of these new antidiabetic drug classes remains unclear. We therefore performed a network meta-analysis to compare the effect on cardiovascular outcomes among GLP-1 RAs, SGLT-2 and dipeptidyl peptidase-4 (DPP-4) inhibitors.

METHODS

MEDLINE, EMBASE, Cochrane database, ClinicalTrials.gov, and congress proceedings from recent cardiology conferences were searched up to April 20, 2019. Cardiovascular outcome trials and renal outcome trials reporting cardiovascular outcomes on GLP-1 RAs, SGLT-2 and DPP-4 inhibitors in patients with type 2 diabetes mellitus were included. The primary outcome was major adverse cardiovascular events (MACE). Secondary outcomes were nonfatal myocardial infarction, nonfatal stroke, cardiovascular mortality, all-cause mortality, hospitalisation for heart failure (HF), and renal composite outcome. ORs and 95% CI were calculated using random-effects models.

RESULTS

Fourteen trials enrolling 121,047 patients were included. SGLT-2 inhibitors reduced cardiovascular deaths and all-cause deaths compared to placebo (OR 0.82, 95% CI 0.73-0.93 and OR 0.84, 95% CI 0.77-0.92) and DPP-4 inhibitors (OR 0.83, 95% CI 0.70-0.99 and OR 0.83, 95% CI 0.73-0.94), respectively. SGLT-2 inhibitors and GLP-1 RAs significantly reduced MACE (OR 0.88, 95% CI 0.82-0.95 and OR 0.87, 95% CI 0.82-0.93), hospitalisation for HF (OR 0.68, 95% CI 0.61-0.77 and OR 0.87, 95% CI 0.82-0.93), and renal composite outcome (OR 0.59, 95% CI 0.52-0.67 and OR 0.86, 95% CI 0.78-0.94) compared to placebo, but SGLT-2 inhibitors reduced hospitalisation for HF (OR 0.79, 95% CI 0.69-0.90) and renal composite outcome (OR 0.69, 95% CI 0.59-0.80) more than GLP-1 RAs. Only GLP-1 RAs reduced nonfatal stroke (OR 0.88, 95% CI 0.77-0.99). DPP-4 inhibitors did not lower the risk of these outcomes when compared to placebo and were associated with higher risks of MACE, hospitalisation for HF, and renal composite outcome when compared to the other two drug classes.

CONCLUSIONS

SGLT-2 inhibitors show clear superiority in reducing cardiovascular and all-cause deaths, hospitalisation for HF, and renal events among new antidiabetic drug classes. GLP-1 RAs also have cardiovascular and renal protective effects. DPP-4 inhibitors have no beneficial cardiovascular effects and are therefore inferior to the other two drug classes. SGLT-2 inhibitors should now be the preferred treatment for type 2 diabetes mellitus.

Determining the Optimal Systolic Blood Pressure for Hypertensive Patients: A Network Meta-analysis

BACKGROUND

There is clinical trial evidence that lowering systolic blood pressure (SBP) to < 120 mm Hg is beneficial, and this has influenced the latest American guideline on hypertension. We therefore used network meta-analysis to study the association between SBP and cardiovascular outcomes.

METHODS

We searched for randomized controlled trials targeting different blood pressure levels that reported cardiovascular events. The mean achieved SBP in each trial was classified into 5 groups (110-119, 120-129, 130-139, 140-149, and 150-159 mm Hg). The primary variables of cardiovascular mortality, stroke, and myocardial infarction were assessed using frequentist and Bayesian approaches.

RESULTS

Fourteen trials with altogether 44,015 patients were included. Stroke and major adverse cardiovascular events were reduced when lowering SBP to 120-129 mm Hg compared with 130-139 mm Hg (odds ratio [OR] 0.83, 95% confidence interval [CI] 0.69-0.99 and OR 0.84, 95% CI 0.73-0.96), 140-149 mm Hg (OR 0.73, 95% CI 0.55-0.97 and OR 0.74, 95% CI 0.60-0.90), and 150-159 mm Hg (OR 0.43, 95% CI 0.26-0.71 and OR 0.41, 95% CI 0.30-0.57), respectively. More intensive control to < 120 mm Hg further reduced stroke (OR 0.58, 95% CI 0.38-0.87; OR 0.51, 95% CI 0.32-0.81; and OR 0.30, 95% CI 0.16-0.56). In contrast, SBP ≥ 150 mm Hg increased myocardial infarction and cardiovascular mortality compared with 120-129 mm Hg (OR 1.73, 95% CI 1.06-2.82 and OR 2.18, 95% CI 1.32-3.59) and 130-139 mm Hg (OR 1.53, 95% CI 1.01-2.32 and OR 1.71, 95% CI 1.11-2.61). No significant relationship between SBP and all-cause mortality was found.

CONCLUSIONS

SBP < 130 mm Hg is associated with a lower risk of stroke and major adverse cardiovascular events. Further lowering to < 120 mm Hg can be considered to reduce stroke risk if the therapy is tolerated. Long-term SBP should not exceed 150 mm Hg because of the increased risk of myocardial infarction and cardiac deaths.

Continual Decrease in Blood Lead Level in Americans: United States National Health Nutrition and Examination Survey 1999-2014

BACKGROUND

Lead is toxic and affects neurodevelopment in children even at low levels. There has been a long-term effort in the United States to reduce exposure to lead in the environment. We studied the latest US population blood lead levels and analyzed its trend.

METHOD

Blood lead levels in 63,890 participants of the National Health Nutrition and Examination Survey 1999-2014 were analyzed using SPSS Complex Samples v22.0 (IBM Corp, Armonk, NY).

RESULTS

Mean blood lead levels and 95% confidence intervals (CIs) were 1.65 μg/dL (1.62-1.68), 1.44 μg/dL (1.42-1.47), 1.43 μg/dL (1.40-1.45), 1.29 μg/dL (1.27-1.32), 1.27 μg/dL (1.25-1.29), 1.12 μg/dL (1.10-1.14), 0.97 μg/dL (0.95-0.99), and 0.84 μg/dL (0.82-0.86) in 1999-2000, 2001-2002, 2003-2004, 2005-2006, 2007-2008, 2009-2010, 2011-2012, and 2013-2014, respectively. Blood lead levels decreased significantly (P <.001), and the trend remained significant when stratified by age, gender, ethnicity, and pregnancy status (P <.05). Estimated percentages of children with blood lead level ≥5 μg/dL were 9.9% (95% CI, 7.5-12.9), 7.4% (95% CI, 5.9-9.4), 5.3% (95% CI, 4.1-6.9), 2.9% (95% CI, 2.1-3.9), 3.1% (95% CI, 2.0-4.8), 2.1% (95% CI, 1.5-3.1), 2.0% (95% CI, 1.0-3.6), and 0.5% (95% CI, 0.3-1.0) in 1999-2000, 2001-2002, 2003-2004, 2005-2006, 2007-2008, 2009-2010, 2011-2012, and 2013-2014, respectively. The decreasing trend was significant (P <.05). In children aged 1 to 5 years in the National Health Nutrition and Examination Survey 2011-2014, the estimated 97.5 percentile of blood lead level was 3.48 μg/dL.

CONCLUSIONS

Blood lead levels have been decreasing in the US population. The reference level also should decrease. It is still important to monitor blood lead levels in the population, especially among pregnant women and children aged 1 to 5 years.