The National Health and Nutrition Examination Survey (NHANES), 2021-2022: Adapting Data Collection in a COVID-19 Environment.

The National Health and Nutrition Examination Survey (NHANES) is a unique source of national data on the health and nutritional status of the US population, collecting data through interviews, standard exams, and biospecimen collection. Because of the COVID-19 pandemic, NHANES data collection was suspended, with more than a year gap in data collection. NHANES resumed operations in 2021 with the NHANES 2021-2022 survey, which will monitor the health and nutritional status of the nation while adding to the knowledge of COVID-19 in the US population. This article describes the reshaping of the NHANES program and, specifically, the planning of NHANES 2021-2022 for data collection during the COVID-19 pandemic. Details are provided on how NHANES transformed its participant recruitment and data collection plans at home and at the mobile examination center to safely collect data in a COVID-19 environment. The potential implications for data users are also discussed. (Am J Public Health. 2021;111(12):2149-2156. https://doi.org/10.2105/AJPH.2021.306517).

Assessing consent for and response to health survey components in an era of falling response rates: National Health and Nutrition Examination Survey, 2011-2018.

Response rates for national population-based surveys have declined, including the National Health and Nutrition Examination Survey (NHANES). Declining response to the initial NHANES interview may impact consent and participation in downstream survey components such as record linkage, physical exams, storage of biological samples and phlebotomy. Interview response rates dropped from 68% in 2011-2012 to 53% in 2017-2018 for adults age 18 and older. Response was higher for children (1-17 years) but with a similar downward trend (2011-2012, 81%; 2017-2018, 65%). Despite declining interview response rates, changes in consent and response rates for downstream components over time have been mixed. Among those interviewed, the examination response rate was over 93%, consent for record linkage was over 90%, and consent for storage of specimens for future research was over 99%. The availability of a blood sample for storage ranged between 60%-65% for children and 78%-85% for adults.

Prevalence and Trends in Hepatitis B Virus Infection in the United States, 2015-2018.

Hepatitis B virus (HBV) is a type of viral hepatitis transmitted through sexual contact, contaminated blood, or from an infected mother to her newborn (1). HBV may cause a liver infection that is acute or short-term, but may also cause chronic or long-term infection. Vaccination was targeted to high-risk groups in 1982, and universal vaccination of newborns was recommended beginning in 1991 in the United States (2). This report provides 2015-2018 prevalence estimates of past or present HBV infection and evidence of hepatitis B vaccination, based on blood collected in the National Health and Nutrition Examination Survey (NHANES).

An Investigation of Nonresponse Bias and Survey Location Variability in the 2017-2018 National Health and Nutrition Examination Survey.

Over the past two decades, a steady decline in response rates on national face-to-face surveys has been documented, with steeper declines observed in recent years. The impact of nonresponse on survey estimates is inconsistent and depends on the correlation between response propensity and the survey estimates. To better understand the impact of declining response rates on the 2017-2018 National Health and Nutrition Examination Survey (NHANES), potential nonresponse bias (NRB) was investigated. NRB was assessed using three approaches: (a) studying variation within the respondent set; (b) benchmarking and comparisons to external data; and (c) comparing alternative weighting adjustments. Because NHANES only samples 30 counties in every 2-year cycle, the sample of counties in any given cycle may be an outlier on some characteristics. Such sampling variability may compound the effects of NRB. For this reason, the representativeness of the 2017-2018 NHANES counties was examined by comparing: (a) the characteristics of the 2017-2018 sampled counties with those from prior cycles; (b) each sampled county with the average of all the counties in the sampling stratum from which that county was selected; and (c) the 2017-2018 counties with 5,000 other samples that could have been drawn under the same sample design using a simulation study. The NRB analyses showed that the 2017-2018 NHANES sample had a lower proportion of college graduates and higher-income individuals compared with prior cycles. Additionally, the 2017-2018 NHANES counties had lower proportions of college graduates and lower mean incomes compared with counties from prior cycles and counties not selected in 2017-2018, which exacerbated the effects of NRB. Weighting adjustments used in prior cycles were not sufficient to address the bias in the 2017-2018 NHANES. Instead, enhanced weighting adjustments for education and income reduced the bias resulting from nonresponse and location sampling variability.

Prevalence and factors associated with self-reported chronic obstructive pulmonary disease among adults aged 40-79: the National Health and Nutrition Examination Survey (NHANES) 2007-2012.

INTRODUCTION: Chronic obstructive pulmonary disease (COPD) is a respiratory disease that often goes undiagnosed, particularly in its early stages. OBJECTIVE: To examine sociodemographic, general health, and COPD specific factors, including severity of lung obstruction, that are associated with healthcare provider-diagnosed COPD among U.S. adults. METHODS: NHANES cross-sectional data collected from 2007-2012 on adults aged 40-79 years (n=10,219) were analyzed. The primary outcome was self-reported COPD diagnosis with predictive factors analyzed via chi-square and logistic regression analyses. RESULTS: During 2007-2012, 5.2% of US adults aged 40-79 reported being diagnosed with COPD. Among those diagnosed, 50.8% reported fair or poor health, 47.1% were currently smoking cigarettes, 49.1% were taking prescription respiratory medication, 36.4% had moderate or worse lung obstruction, and nearly 90% had one or more respiratory symptoms. Logistic regression revealed positive associations between receiving a COPD diagnosis and the following: being white (AOR: 3.08, 95% CI: 1.82-5.20); being aged 60-79 years (AOR: 1.65, 95% CI: 1.07-2.53); reporting fair/poor health (AOR: 2.91, CI: 1.55-5.46); having 4-9 (AOR: 3.5, CI: 1.3-9.4) or 10 or more healthcare visits in prior year (AOR: 5.06, CI: 1.62-15.77); being a former (AOR: 1.75, CI: 1.2-2.5) or current smoker (AOR: 1.70, CI: 1.17-2.48); having more severe lung obstruction (AOR: 4.90, CI: 3.28-7.32); having 3 or more respiratory symptoms (AOR: 22.07, CI: 12.03-40.49). CONCLUSIONS: Multiple factors are associated with self-reported COPD diagnosis with number of reported respiratory symptoms having the strongest association. After controlling for other factors, having mild lung obstruction was not associated with being diagnosed.

Prevalence of Herpes Simplex Virus Type 1 and Type 2 in Persons Aged 14-49: United States, 2015-2016.

Herpes simplex virus types 1 and 2 (HSV-1 and HSV-2) are common, lifelong infections, which often have no symptoms (1). People with symptoms may have painful blisters or sores at the site of infection (2,3). The viruses are transmitted through contact with an infected person's lesion, mucosal surface, or genital or oral secretions. This report provides recent national estimates of HSV-1 and HSV-2 antibody prevalence from the 2015­2016 National Health and Nutrition Examination Survey (NHANES) among persons aged 14­49 by age, sex, and race and Hispanic origin, and examines trends in prevalence by race and Hispanic origin from 1999­2000 to 2015­2016.

Characteristics of U.S. Adults With Hypertension Who Are Unaware of Their Hypertension, 2011-2014.

KEY FINDINGS: Data from the National Health and Nutrition Examination Survey •In 2011-2014, 15.9% of adults with hypertension were unaware of their hypertension. This was a 46% decline since 1999-2002 (29.5%). •A higher percentage of men (19.2%) than women (12.9%) and younger (aged 18-39, 30.8%) than older (aged 60 and over, 12.5%) adults with hypertension were unaware of their condition. •A higher percentage of non-Hispanic Asian (24.7%) and Hispanic (20.2%) adults than non-Hispanic white (14.9%) and non-Hispanic black (14.7%) adults with hypertension were unaware of their condition. •Almost 30% of adults with hypertension who had no health insurance were unaware of their hypertension compared with 14.4% of those with insurance. •As health care visits increased, the percentage of adults with hypertension who were unaware of their status decreased. High blood pressure is a risk factor for multiple diseases, including heart disease, stroke, and kidney disease (1). In 2011-2014, about 29% of U.S. adults had hypertension (2). Adults with hypertension who are undiagnosed and unaware of their hypertension will not be treated, and their blood pressure may remain above normal levels with damaging effects. Therefore, diagnosis and awareness of hypertension are essential for blood pressure management and control. This report presents recent national estimates of adults with hypertension who are unaware of their hypertension, that is, they reported not being told by a doctor or health care provider that they had high blood pressure.

Prevalence of HPV in Adults Aged 18-69: United States, 2011-2014.

KEY FINDINGS: Data from the National Health and Nutrition Examination Survey Human papillomavirus (HPV) is the most common sexually transmitted infection in the United States (1). Some HPV types can cause genital warts and are considered low risk, with a small chance for causing cancer. Other types are considered high risk, causing cancer in different areas of the body including the cervix and vagina in women, penis in men, and anus and oropharynx in both men and women (2). This report provides the most recent national estimates of oral HPV prevalence among adults aged 18-69 from the National Health and Nutrition Examination Survey (NHANES) 2011-2014, as well as prevalence of genital HPV among adults aged 18-59 from NHANES 2013-2014. Estimates of any HPV (37 types tested) as well as high-risk HPV (14 of the 37 types) are provided.

TPrevalence of HPV in Adults Aged 18-69: United States, 2011-2014.

KEY FINDINGS: Data from the National Health and Nutrition Examination Survey ● During 2011-2014, prevalence of any oral human papillomavirus (HPV) for adults aged 18-69 was 7.3%; high-risk HPV was 4.0%. ● Overall, prevalence of any and high-risk oral HPV was lowest among non-Hispanic Asian adults; any oral HPV was highest among non-Hispanic black adults. ● Prevalence of any and high-risk oral HPV was higher in men than women except for high-risk HPV among Asian adults. ● During 2013-2014, prevalence of any and high-risk genital HPV for adults aged 18-59 was 45.2% and 25.1% in men and 39.9% and 20.4% in women, respectively. ● Prevalence of any and high-risk genital HPV was lower among non-Hispanic Asian and higher among non-Hispanic black than both non-Hispanic white and Hispanic men and women. Human papillomavirus (HPV) is the most common sexually transmitted infection in the United States (1). Some HPV types can cause genital warts and are considered low risk, with a small chance for causing cancer. Other types are considered high risk, causing cancer in different areas of the body including the cervix and vagina in women, penis in men, and anus and oropharynx in both men and women (2). This report provides the most recent national estimates of oral HPV prevalence among adults aged 18-69 from the National Health and Nutrition Examination Survey (NHANES) 2011-2014, as well as prevalence of genital HPV among adults aged 18-59 from NHANES 2013-2014. Estimates of any HPV (37 types tested) as well as high-risk HPV (14 of the 37 types) are provided.

Overview of Asian American Data Collection, Release, and Analysis: National Health and Nutrition Examination Survey 2011-2018.

Data System. The National Health and Nutrition Examination Survey (NHANES), conducted by the National Center for Health Statistics, is a cross-sectional survey on the health and nutritional status of US adults and children. Data Collection/Processing. A complex, multistage probability design is used to select a sample representative of the US civilian, noninstitutionalized population. NHANES includes in-home interviews, physical examinations, and biospecimen collection. About 5000 persons are examined annually. Since 2011, NHANES has been oversampling Asian Americans in addition to traditionally oversampled groups, including Hispanics and non-Hispanic Blacks. Data Analysis/Dissemination. Data are publicly released online in 2-year cycles. Some data, because of disclosure risk, are only available through the Research Data Center. Data users should read documentation, examine sample sizes and response rates, and account for the complex survey design. With publicly released data, analyses of Asians as a single group is only possible; some Asian subgroup analyses may be conducted through the Research Data Center. Public Health Implications. Oversampling Asians in NHANES 2011-2018 allows national estimates to be computed on health conditions, nutrition, and risk factors of public health importance on this growing subpopulation of Asian Americans.

Viral Hepatitis Among Non-Hispanic Asian Adults in the United States, 2011-2014.

KEY FINDINGS: Hepatitis A (HAV), B (HBV), and C (HCV) viruses are common types of viral hepatitis. HBV and HCV infection can lead to liver disease, cancer, and serious health consequences. HAV and HBV infections are high among Asian persons, especially those born outside the United States (1-3). This report provides 2011- 2014 National Health and Nutrition Examination Survey (NHANES) estimates on prevalence of antibody to HAV (from infection or immunization), past or current HBV infection, and current HCV infection, by race and Hispanic origin.

Prevalence and trends in psychotropic medication use among US male veterans, 1999-2010.

PURPOSE: Prior studies of psychotropic medication use among US veterans are limited in their ability to generalize estimates to the full veteran population and make comparisons with non-veterans. This study estimated the prevalence of psychotropic medication use and trends over time among male US veterans, compared their use of psychotropic medications with non-veteran males, and examined differences among veteran subpopulations. METHODS: The data for our analysis came from the National Health and Nutrition Examination Survey (1999-2010), a cross-sectional, nationally representative study of the civilian, non-institutionalized US population. RESULTS: The percentage of male veterans who used any psychotropic medication increased from 10.4% in 1999-2002 to 14.3% in 2003-2006, then remained stable in 2007-2010 (14.0%). During the same time period, the percentage of non-veteran males who used psychotropic medications remained relatively stable (7.0%, 8.3%, and 9.2%, respectively). Veterans were more likely to use psychotropic medication, specifically antidepressants, than non-veterans. The percentage of non-Hispanic white veterans and veterans aged 60 years and over who used psychotropic medications increased between 1999-2002 and 2003-2006, but the percentages remained stable between 2003-2006 and 2007-2010. In 2003-2006 and 2007-2010, a higher percentage of non-Hispanic white veterans used psychotropic medications than non-Hispanic black veterans. CONCLUSIONS: This study found that the use of psychotropic medications and antidepressants was higher among male veterans than male non-veterans, and that prevalence of use increased between 1999-2002 and 2007-2010 for male veterans but remained relatively stable for non-veterans. There were significant variations in the use of psychotropic medications among veteran subpopulations.

Lung obstruction among adults aged 40-79: United States, 2007-2012.

During 2007-2012, 14.7% of U.S. adults aged 40­79 had lung obstruction, with almost two-thirds having mild lung obstruction (9.4%) and one-third having moderate or worse obstruction (5.3%). A similar percentage of men and women had any lung obstruction, a pattern that persisted at each level of severity. There were notable differences in lung obstruction by race and Hispanic origin. Overall and at both levels of severity, rates of lung obstruction were higher for non-Hispanic white and non- Hispanic black adults compared with Hispanic adults. Overall and at the mild lung obstruction level, the percentage of non-Hispanic white adults with lung obstruction was significantly higher than that of non-Hispanic black adults. Lung obstruction also varied by education level. Adults who had attended college had a significantly lower percentage of moderate or worse lung obstruction compared with adults with less education. Among adults with mild lung obstruction, percentages were similar by education level. More than one-half of adults aged 40­79 with lung obstruction reported having at least one respiratory symptom. Reporting rates for each symptom and for one or more symptoms were all higher for those adults with moderate or worse lung obstruction than for those with mild obstruction. Among adults with moderate or worse lung obstruction, more than 80% reported having at least one respiratory symptom.

Cigarette smoking and lung obstruction among adults aged 40-79: United States, 2007-2012.

During 2007-2012, about 46% of U.S. adults aged 40-79 with lung obstruction currently smoked cigarettes. This was more than double the smoking rate for those without lung obstruction (19.8%). In the United States, a greater percentage of men (20.5%) than women (15.3%) were current cigarette smokers in 2013. Some studies have suggested that women are more susceptible than men to the effects of tobacco smoke. Since 2000, the number of women dying from COPD has exceeded the number of men dying from the disease. In the present report, a similar percentage of men and women overall, and at each level of lung obstruction severity, currently smoked cigarettes. Notable differences were seen in smoking rates by race and Hispanic origin. Among adults aged 40-79 with mild lung obstruction, a significantly greater percentage of non-Hispanic black adults currently smoked cigarettes compared with the two other race and Hispanic origin groups. With moderate or worse lung obstruction, however, a significantly greater percentage of non-Hispanic white adults currently smoked cigarettes compared with those in the other race and Hispanic origin groups. Smoking rates among those with lung obstruction also varied by education, with progressively higher rates of smoking among those with decreasing levels of education. This inverse relationship between smoking and education level is consistent across all severity levels of lung obstruction. Smoking tobacco can increase respiratory symptoms, loss of lung function, and the progression of COPD. The data presented here show that during 2007-2012, almost one-half of U.S. adults aged 40-79 with lung obstruction currently smoked cigarettes.

Prevalence of Airflow Obstruction in U.S. Adults Aged 40-79 Years: NHANES Data 1988-1994 and 2007-2010.

BACKGROUND: The study evaluated the change in the prevalence of airflow obstruction in the U.S. population 40-79 years of age from years 1988-1994 to 2007-2010. METHODS: Spirometry data from two representative samples of the U.S. population, the National Health and Nutrition Examination Surveys (NHANES) conducted in 1988-1994 and 2007-2010, were used. The American Thoracic Society/European Respiratory Society (ATS/ERS) criteria were used to define airflow obstruction. RESULTS: Based on ATS/ERS criteria, the overall age-adjusted prevalence of airflow obstruction among adults aged 40-79 years decreased from 16.6% to 14.5% (p < 0.05). Significant decreases were observed for the older age category 60-69 years (20.2% vs. 15.4%; p < 0.01), for males (19.0% vs. 15.4%; p < 0.01), and for Mexican American adults (12.7% vs. 8.4%; p < 0.001). The prevalence of moderate and more severe airflow obstruction decreased also (6.4% vs. 4.4%; p < 0.01). Based on ATS/ERS criteria, during 2007-2010, an estimated 18.3 million U.S. adults 40-79 years had airflow obstruction, 5.6 million had moderate or severe airflow obstruction and 1.4 million had severe airflow obstruction. CONCLUSIONS: The overall age-adjusted prevalence of airflow obstruction among U.S. adults aged 40-79 years decreased from 1988-1994 to 2007-2010, especially among older adults, Mexican Americans, and males.

Prescription cholesterol-lowering medication use in adults aged 40 and over: United States, 2003-2012.

During 2003­2012, there was a significant increase in the percentage of adults aged 40 and over who used a prescription cholesterol-lowering medication. In 2003­2004, one in five adults reported using a prescription cholesterol-lowering medication in the past 30 days. By 2011­2012, that number had risen to one in four adults. In 2011­2012, the majority of adults using a cholesterol-lowering medication reported using a statin alone (83%). Ten percent used both a statin and a nonstatin and another 7% used only a nonstatin. Simvastatin was the most commonly used medication, with 42% of all cholesterol-lowering medication users reporting its use, followed by atorvastatin (20.2%). Use of a prescription cholesterol-lowering medication increased with age but was similar between men and women and race and Hispanic origin groups. Adults aged 40­64 who reported having health insurance or prescription medication coverage were more likely to take prescription cholesterol-lowering medications. Hypercholesterolemia or high cholesterol is one of the most common preventable risk factors for atherosclerotic CVD. In 2011­2012, more than 30 million Americans aged 20 and over (13%) had measured high total cholesterol (5). There is extensive and consistent evidence supporting the use of cholesterol-lowering medication, especially statins, in addition to lifestyle changes, to treat lipid disorders and reduce atherosclerotic CVD events. The 2013 cholesterol treatment guidelines updated recommendations for statin therapy on the basis of low-density lipid cholesterol levels and atherosclerotic CVD risks (6). Approximately 71% of adults with diagnosed CVD, 63% of those with diagnosed diabetes, and 54% of those with diagnosed hypercholesterolemia reported taking prescription cholesterol-lowering medications.

Perception of weight status in U.S. children and adolescents aged 8-15 years, 2005-2012.

Childhood obesity is a major public health problem associated with many adverse health outcomes in adulthood (1). During 2011­2012, nearly 17% of children and adolescents were obese (2). Weight status misperception occurs when the child's perception of their weight status differs from their actual weight status based on measured height and weight. Accurate weight status self-perception has been linked to appropriate weight control behaviors in youth. The National Health and Nutrition Examination Survey (NHANES) data for children and adolescents aged 8­15 years offers an opportunity to examine weight perception status in this age group.

Data needs for B-24 and beyond: NHANES data relevant for nutrition surveillance of infants and young children.

The period from birth to 24 mo (B-24) is a critical phase in which nutrient requirements for growth and development are high and several transitions in food consumption practices occur. A few large-scale national studies (eg, the Feeding Infants and Toddlers Study and Infant Feeding Practices Study) offer important insights into infant feeding practices and food consumption patterns in young children in the United States. The NHANES collects comprehensive cross-sectional data on the nutrition and health of Americans including infants and toddlers. This article describes the NHANES program and data from NHANES 1999-2010 on young children that are relevant for the B-24 Project. NHANES is a nationally representative survey of the noninstitutionalized US population that combines personal interviews with standardized physical examination and measurements via mobile examination centers. Data on infant feeding practices (breastfeeding and timing of introduction and nature of complementary foods), dietary intake (two 24-h recalls), and nutrient supplements are collected. Data on demographic characteristics, anthropometric measurements, biomarkers of nutrient status, food security, and participation in federal nutrition programs are also available. Data can be accessed online, downloaded, and pooled over several survey cycles, allowing examination of infant feeding practices, food and nutrient intakes, and nutritional status of Americans <2 y old. Subgroup analyses by race-ethnicity and income status are also possible. NHANES responds to evolving data needs, as feasible, in the context of the survey design, research priorities, and funding. It offers a vehicle for potentially gathering additional data on children <2 y to address the objectives of the B-24 Project in the future.

Estimating the U.S. prevalence of chronic obstructive pulmonary disease using pre- and post-bronchodilator spirometry: the National Health and Nutrition Examination Survey (NHANES) 2007-2010.

BACKGROUND: During 2007-2010, the National Health and Nutrition Examination Survey (NHANES) conducted a spirometry component which obtained pre-bronchodilator pulmonary lung function data on a nationally representative sample of US adults aged 6-79 years and post-bronchodilator pulmonary lung function data for the subset of adults with airflow limitation. The goals of this study were to 1) compute prevalence estimates of chronic obstructive pulmonary disease (COPD) using pre-bronchodilator and post-bronchodilator spirometry measurements and fixed ratio and lower limit of normal (LLN) diagnostic criteria and 2) examine the potential impact of nonresponse on the estimates. METHODS: This analysis was limited to those aged 40-79 years who were eligible for NHANES pre-bronchodilator spirometry (n=7,104). Examinees with likely airflow limitation were further eligible for post-bronchodilator testing (n=1,110). Persons were classified as having COPD based on FEV1/FVC < 70% (fixed ratio) or FEV1/FVC < lower limit of normal (LLN) based on person's age, sex, height, and race/ethnicity. Those without spirometry but self-reporting both daytime supplemental oxygen therapy plus emphysema and/or current chronic bronchitis were also classified as having COPD. The final analytic samples for pre-bronchodilator and post-bronchodilator analyses were 77.1% (n=5,477) and 50.8% (n=564) of those eligible, respectively. To account for non-response, NHANES examination weights were adjusted to the eligible pre-bronchodilator and post-bronchodilator subpopulations. RESULTS: In 2007-2010, using the fixed ratio criterion and pre-bronchodilator test results, COPD prevalence was 20.9% (SE 1.1) among US adults aged 40-79 years. Applying the same criterion to post-bronchodilator test results, prevalence was 14.0% (SE 1.0). Using the LLN criterion and pre-bronchodilator test results, the COPD prevalence was 15.4% (SE 0.8), while applying the same criterion to post-bronchodilator test results, prevalence was 10.2% (SE 0.8). CONCLUSIONS: The overall COPD prevalence among US adults aged 40-79 years varied from 10.2% to 20.9% based on whether pre- or post-bronchodilator values were used and which diagnostic criterion (fixed ratio or LLN) was applied. The overall prevalence decreased by approximately 33% when airflow limitation was based on post-bronchodilator as compared to pre-bronchodilator spirometry, regardless of which diagnostic criterion was used.