Waist Circumference Measurement Methodology Study: National Health and Nutrition Examination Survey, 2016.

Objective This report compares five methods of waist circumference (WC) measurements: 1) the National Heart, Lung, and Blood Institute (NHLBI-WC); 2) the World Health Organization (WHO-WC); 3) the Multi-Ethnic Study of Atherosclerosis (MESA-WC) using Gulick II Plus tape; 4) the Multi-Ethnic Study of Atherosclerosis (MESA-WC) using Lufkin tape; and 5) assisted self-measurement over clothes (MESA-assisted). Method During 2016, measurements were obtained from 2,297 participants aged 20 and over, who participated in the National Health and Nutrition Examination Survey (NHANES). The mean differences and sensitivity and specificity for abdominal obesity (AO) were calculated between the NHLBI-WC (reference) and the other four WC measurements. Results The mean difference between NHLBI-WC and WHO-WC was 0.81 cm for men and 3.21 cm for women ( p ≤ 0.0125 for both); between NHLBI-WC and MESA-WC (Gulick) was -0.68 cm for men ( p ≤ 0.0125) and -0.89 cm for women; between NHLBI-WC and MESA-WC (Lufkin) was 0.02 cm for men and 0.08 cm for women; and between NHLBI-WC and MESA-assisted was -0.71 cm for men and 1.34 cm for women ( p ≤ 0.0125 for both). Sensitivity and specificity for AO, with NHLBI-WC as a reference, for men were greater than 90% for all methods; for women, sensitivity and specificity for AO for MESA-WC (Lufkin) were greater than 90%; for women, WHO-WC, MESAWC (Gulick), and MESA-assisted methods were greater than 85%.

Urine sodium excretion increased slightly among U.S. adults between 1988 and 2010.

Little information is available on temporal trends in sodium intake in the U.S. population using urine sodium excretion as a biomarker. Our aim was to assess 1988-2010 trends in estimated 24-h urine sodium (24hUNa) excretion among U.S. adults (age 20-59 y) participating in the cross-sectional NHANES. We used subsamples from a 1988-1994 convenience sample, a 2003-2006 one-third random sample, and a 2010 one-third random sample to comply with resource constraints. We estimated 24hUNa excretion from measured sodium concentrations in spot urine samples by use of calibration equations (for men and women) derived from the International Cooperative Study on Salt, Other Factors, and Blood Pressure study. Estimated 24hUNa excretion increased over the 20-y period [1988-1994, 2003-2006, and 2010; means ± SEMs (n): 3160 ± 38.4 mg/d (1249), 3290 ± 29.4 mg/d (1235), and 3290 ± 44.4 mg/d (525), respectively; P-trend = 0.022]. We observed significantly higher mean estimated 24hUNa excretion in each survey period (P < 0.001) for men compared with women (31-33%) and for persons with a higher body mass index (BMI; 32-35% for obese vs. normal weight) or blood pressure (17-26% for hypertensive vs. normal blood pressure). After adjusting for age, sex, and race-ethnicity, temporal trends in mean estimated 24hUNa excretion remained significant (P-trend = 0.004). We observed no temporal trends in mean estimated 24hUNa excretion among BMI subgroups, nor after adjusting for BMI. Although several limitations apply to this analysis (the use of a convenience sample in 1988-1994 and using estimated 24hUNa excretion as a biomarker of sodium intake), these first NHANES data suggest that mean estimated 24hUNa excretion increased slightly in U.S. adults over the past 2 decades, and this increase may be explained by a shift in the distribution of BMI.

Changes in measurement procedure from a radioassay to a microbiologic assay necessitate adjustment of serum and RBC folate concentrations in the U.S. population from the NHANES 1988-2010.

The NHANES measured serum and RBC folate concentrations by using a radioassay during prefortification (1988-1994) and postfortification (1999-2006) periods followed by the use of a microbiologic assay (MBA) from 2007-2010. The MBA produces higher concentrations than does the radioassay and is considered to be more accurate. To allow for accurate long-term trending (1988-2010), we evaluated different regression models (linear, piecewise linear, and fractional polynomial) to assay-adjust the radioassay results to be comparable to the MBA results. The data used to derive the regression models originated from 2 crossover studies in which the 2 assays were applied to a set of 325 serum and 171 whole-blood samples. Fractional polynomial regression of logarithmically transformed data provided the best fit for serum folate. Linear regression of logarithmically transformed whole-blood data provided an equally good fit compared with the other models and was the simplest to apply for RBC folate. Prefortification serum and RBC folate geometric mean concentrations increased after adjustment from 13.0 to 16.7 nmol/L and from 403 to 747 nmol/L, respectively. Postfortification serum folate concentrations increased from ~30 to ~43 nmol/L, and RBC folate concentrations increased from ~600 to ~1100 nmol/L after adjustment, with some variation across survey cycles. The presented regression equations allow the estimation of more accurate prevalence estimates and long-term trends in blood folate concentrations in the U.S. population by using results that are equivalent to the MBA. This information will be useful to public health officials in the United States who are dealing with folic acid fortification issues.

Estimation of trends in serum and RBC folate in the U.S. population from pre- to postfortification using assay-adjusted data from the NHANES 1988-2010.

The NHANES has monitored folate status of the U.S. population from prefortification (1988-1994) to postfortification (1999-2010) by measuring serum and RBC folate concentrations. The Bio-Rad radioassay (BR) was used from 1988 to 2006, and the microbiologic assay (MBA) was used from 2007 to 2010. The MBA produces higher concentrations than the BR and is considered to be more accurate. Thus, to bridge assay differences and to examine folate trends over time, we adjusted the BR results to be comparable to the MBA results. Postfortification, assay-adjusted serum and RBC folate concentrations were 2.5 times and 1.5 times prefortification concentrations, respectively, and showed a significant linear trend (P < 0.001) to slightly lower concentrations during 1999-2010. The postfortification prevalence of low serum (<10 nmol/L) or RBC (<340 nmol/L) folate concentrations was ≤ 1%, regardless of demographic subgroup, compared with 24% for serum folate and 3.5% for RBC folate prefortification, with substantial variation among demographic subgroups. The central 95% reference intervals for serum and RBC folate varied by demographic subgroup during both pre- and postfortification periods. Age and dietary supplement use had the greatest effects on prevalence estimates of low folate concentrations during the prefortification period. In summary, the MBA-equivalent blood folate concentrations in the U.S. population showed first a sharp increase from pre- to postfortification, then showed a slight decrease (17% for serum and 12% for RBC folate) during the 12-y postfortification period. The MBA-equivalent pre- and postfortification reference concentrations will inform countries that plan folic acid fortification or that need to evaluate its impact.

Differences in Hypertension Prevalence and Hypertension Control by Urbanization Among Adults in the United States, 2013-2018.

BACKGROUND: To examine the associations between urbanization and hypertension, stage II hypertension, and hypertension control. METHODS: Data on 16,360 US adults aged 18 years or older from the 2013-2018 National Health and Nutrition Examination Survey (NHANES) were used to estimate the prevalence of hypertension (blood pressure (BP) ≥130/80 mm Hg or use of medication for hypertension), stage II hypertension (BP ≥140/90 mm Hg), and hypertension control (BP <130/80 mm Hg among hypertensives) by urbanization, classified by levels of metropolitan statistical areas as large MSAs (population ≥1,000,000), medium to small MSAs (population 50,000-999,999), and non-MSAs (population <50,000). RESULTS: All prevalence ratios (PRs) were compared with large MSAs and adjusted for demographics and risk factors. The PRs of hypertension were 1.07 (95% confidence interval (CI) = 0.99-1.14) for adults residing in medium to small MSAs and 1.06 (95% CI = 0.99-1.13) for adults residing in non-MSAs. For stage II hypertension, the PRs were higher for adults residing in medium to small MSAs 1.21 (95% CI = 1.06-1.36) but not for adults residing in non-MSAs 1.06 (95% CI = 0.88-1.29). For hypertension control, the PRs were 0.96 (95% CI = 0.91-1.01) for adults residing in medium to small MSAs and 1.00 (95% CI = 0.93-1.06) for adults residing in non-MSAs. CONCLUSIONS: Among US adults, urbanization was associated with stage II hypertension.

Differences in Hypertension and Stage II Hypertension by Demographic and Risk Factors, Obtained by Two Different Protocols in US Adults: National Health and Nutrition Examination Survey, 2017-2018.

BACKGROUND: To compare prevalence of hypertension and stage II hypertension assessed by 2 blood pressure (BP) observation protocols. METHODS: Participants aged 18 years and older (n = 4,689) in the National Health and Nutrition Examination Survey (NHANES 2017-2018) had their BP measured following 2 protocols: the legacy auscultation protocol (AP) and oscillometric protocol (OP). The order of protocols was randomly assigned. Prevalence estimates for hypertension (BP ≥130/80 mm Hg or use of medication for hypertension) and stage II hypertension (BP ≥140/90 mm Hg) were determined overall, by demographics, and by risk factors for each protocol. Ratios (OP% ÷ AP%) and kappa statistics were calculated. RESULTS: Age-adjusted hypertension prevalence was 44.5% (95% confidence interval [CI]: 41.1%-48.0%) using OP and 45.1% (95% CI: 41.5%-48.7%) using AP, prevalence ratio = 0.99 (95% CI = 0.94-1.04). Age-adjusted stage II hypertension prevalence was 15.8% (95% CI: 13.6%-18.2%) using AP and 17.1% (95% CI: 14.7%-19.7%) using OP, prevalence ratio = 0.92 (95% CI = 0.81-1.04). For both hypertension and stage II hypertension, the prevalence ratios by demographics and by risk factors all included unity in their 95% CI, except for stage II hypertension in adults 60+ years (ratio: 0.88 [95% CI: 0.78-0.98]). Kappa for agreement between protocols for hypertension and stage II hypertension was 0.75 (95% CI = 0.71-0.79) and 0.67 (95% CI = 0.61-0.72), respectively. CONCLUSIONS: In adults and for nearly all subcategories there were no significant differences in prevalence of hypertension and stage II hypertension between protocols, indicating that protocol change may not affect the national prevalence estimates of hypertension and stage II hypertension.

Developing equations to predict waist circumference measurements based on the National Heart, Lung, and Blood Institute method from the World Health Organization method.

PURPOSE: The purpose of the study was to convert waist circumference (WC) measurements obtained by the World Health Organization (WHO-WC) method to the National Heart, Lung, and Blood Institute (NHLBI-WC) method. METHODS: During 2016, the National Health and Nutrition Examination Survey participants aged 20 years and older had two different WC measurements taken (n = 2405). The mean differences in the WC between the NHLBI-WC and WHO-WC measurements were calculated. Multivariable prediction models were developed to predict the NHLBI-WC from the measured WHO-WC. Sensitivity and specificity of the abdominal obesity classification (AOC) were calculated for the measured WHO-WC and the predicted NHLBI-WC. Kappa coefficients were calculated to evaluate the agreements between the AOC derived from the NHLBI-WC and from the WHO-WC and the predicted NHLBI-WC. RESULTS: The mean differences between the NHLBI-WC and WHO-WC were 0.8 cm for males and 3.2 cm for females (P ≤ .05). Sensitivity of the AOC for the measured WHO-WC was 93% for males and 87% for females, and the specificity of the AOC was 97% or greater for both genders. Sensitivity and specificity of the AOC for the predicted NHLBI-WC were 95% or greater for both genders. The AOC derived from the predicted NHLBI-WC had higher agreements for both genders. CONCLUSIONS: The prediction equations provided may be used to predict the NHLBI-WC from the WHO-WC for comparability in WC estimates across studies.

Cardiorespiratory fitness levels among US adults 20-49 years of age: findings from the 1999-2004 National Health and Nutrition Examination Survey.

Data from the 1999-2004 National Health and Nutrition Examination Survey were used to describe the distribution of cardiorespiratory fitness and its association with obesity and leisure-time physical activity (LTPA) for adults 20-49 years of age without physical limitations or indications of cardiovascular disease. A sample of 7,437 adults aged 20-49 years were examined at a mobile examination center. Of 4,860 eligible for a submaximal treadmill test, 3,250 completed the test and were included in the analysis. The mean maximal oxygen uptake ( max) was estimated as 44.5, 42.8, and 42.2 mL/kg/minute for men 20-29, 30-39, and 40-49 years of age, respectively. For women, it was 36.5, 35.4, and 34.4 mL/kg/minute for the corresponding age groups. Non-Hispanic black women had lower fitness levels than did non-Hispanic white and Mexican-American women. Regardless of gender or race/ethnicity, people who were obese had a significantly lower estimated maximal oxygen uptake than did nonobese adults. Furthermore, a positive association between fitness level and LTPA participation was observed for both men and women. These results can be used to track future population assessments and to evaluate interventions. The differences in fitness status among population subgroups and by obesity status or LTPA can also be used to develop health policies and targeted educational campaigns.

Contribution of Whole Grains to Total Grains Intake Among Adults Aged 20 and Over: United States, 2013-2016.

Total grains intake comes from whole grains and refined grains. Whole grains contain the entire grain kernel (bran, germ, and endosperm) (1). A higher intake of whole grains is linked with a lower risk of cardiovascular disease, cancer, and mortality (2). The "2015-2020 Dietary Guidelines for Americans" recommend that at least one-half of total grains intake be from whole grains (3). This report provides estimates of the percentage of total grains intake consumed from whole grains sources, for adults aged 20 and over who reported consumption of grains (98.6%) on a given day during 2013-2016.

Are demographic characteristics, health care access and utilization, and comorbid conditions associated with hypertension among US adults?

BACKGROUND: Little is known about the factors associated with hypertension awareness, treatment, and control. We examined the association of demographic and socioeconomic characteristics, risk factors, health care access and utilization, and hypertension awareness, treatment, and control. METHODS: The National Health and Nutrition Examination Survey (NHANES) 1999-2004, a continuous, annual survey of the civilian non-institutionalized US population. The sample comprised 4,816 hypertensive persons aged 20+ years. RESULTS: Adults > or =60 years were more likely to have uncontrolled hypertension compared with adults 40-59 years old (60-69 years old: odds ratio (OR) 1.69, confidence interval (CI) 1.31-2.17; 80+ years old: OR 3.56, CI 2.42-5.25, respectively). Compared to men, women were more likely to have uncontrolled hypertension (OR 1.29, CI 1.01-1.64). When compared with non-Hispanic whites, non-Hispanic blacks were more likely to have uncontrolled hypertension (OR 1.40, CI 1.10-1.79). Diabetes and Poverty Income Ratio (PIR) classification of <1 were associated with increased likelihood of uncontrolled hypertension (OR 2.69, CI 1.99-3.63; OR 1.68, CI 1.19-2.37; respectively). Persons without health insurance had higher odds of being untreated when compared with insured persons (OR 2.38, CI 1.71-3.32). Younger age (20-39 years), lack of risk factors for hypertension and less health care were associated with increased odds of being unaware of hypertension. CONCLUSIONS: Uncontrolled hypertension is more likely among women, older persons (> or =60 years), non-Hispanic blacks, the poor, and diabetics. Hypertension awareness and treatment is lower among the young (20-39 years), the uninsured, individuals reporting fewer health risk factors, and adults with less exposure and utilization of health care.

Factors Associated With Hypertension Control in US Adults Using 2017 ACC/AHA Guidelines: National Health and Nutrition Examination Survey 1999-2016.

BACKGROUND: Factors and trends associated with hypertension control (BP < 130/80 mm Hg) and mean blood pressure (BP) among hypertensive adults (BP ≥1 30/80 mm Hg or medicated for hypertension). METHOD: Data on 22,911 hypertensive US adults from the 1999-2016 National Health and Nutrition Examination Survey. RESULTS: For men, hypertension control prevalence increased from 8.6% in 1999-2000 to 16.2% in 2003-2004 (P < 0.001), and continued the increasing trend afterwards to 23.2% in 2011-2012 (P < 0.001) and then plateaued. For women, hypertension control prevalence increased from 1999-2000 to 2009-2010 (10.8-26.3%, P < 0.001) and then plateaued. For men with hypertension, systolic BP decreased from 1999-2000 to 2011-2012 (135.7-132.8 mm Hg, P < 0.001) and then increased to 135.3 mm Hg in 2015-2016 (P < 0.001). For women with hypertension, systolic BP decreased from 1999-2000 to 2009-2010 (139.7-131.9 mm Hg; P < 0.001) and then increased to 134.4 mm Hg in 2015-2016 (P = 0.003). Diastolic BP decreased from 1999-2000 to 2015-2016 (men: 79.1-75.5 mm Hg and women: 76.4-73.7 mm Hg, P < 0.001 for both). In 2011-2016, hypertension control was 22.0% for men and 25.2% for women. The adjusted prevalence ratio (PR) of hypertension control were lower for non-Hispanic black men and women (PR = 0.72, 95% confidence interval (CI) = 0.61-0.86; PR = 0.83, 95% CI = 0.70-0.99, respectively; non-Hispanic white (NHW) as reference), Hispanic and non-Hispanic Asian men (PR = 0.70, 95% CI = 0.54-0.92; PR = 0.59, 95% CI = 0.39-0.86; respectively; NHW as reference). CONCLUSION: Hypertension control significantly increased from 1999-2000 to 2011-2012 (men) and 2009-2010 (women) and then plateaued. About a quarter of US adults with hypertension were controlled in 2011-2016.

Prevalence of Depression Among Adults Aged 20 and Over: United States, 2013-2016.

Major depression is a common and treatable mental disorder characterized by changes in mood, and cognitive and physical symptoms over a 2-week period (1). It is associated with high societal costs (2) and greater functional impairment than many other chronic diseases, including diabetes and arthritis (3). Depression rates differ by age, sex, income, and health behaviors (4). This report provides the most recent national estimates of depression among adults. Prevalence of depression is based on scores from the Patient Health Questionnaire (PHQ-9), a symptom-screening questionnaire that allows for criteria-based diagnoses of depressive disorders (5). Estimates for non-Hispanic Asian persons are presented for the first time.

Mean mid-arm circumference and blood pressure cuff sizes for US children, adolescents and adults: National Health and Nutrition Examination Survey, 2011-2016.

BACKGROUND: Measuring blood pressure (BP) requires an appropriate BP cuff size given measured mid-arm circumference (mid-AC). OBJECTIVE: To provide mid-AC means and percentiles for US population aged more than 3 years and examine the frequency distribution of mid-AC cuffed by Baum and Welch Allyn cuff systems. PATIENTS AND METHODS: The 2011-2016 National Health and Nutrition Examination Survey, a cross-sectional survey, was used to estimate mean mid-AC (n=24 723). RESULTS: Mean mid-AC did not differ from 2011 to 2016 (31.0 vs. 31.3 cm, P>0.05). During 2011-2016, mean mid-AC was greater for males than females (32.0 vs. 30.4 cm, P<0.001) and was largest among adults 40-49 years (34.0 cm). Non-Hispanic Black persons had the largest mean mid-AC (32.0 cm) and non-Hispanic Asian persons the smallest (28.4 cm). Increased BMI was associated with increased mean mid-AC for those 3-19 years (normal, 22.0 cm and obese, 31.5 cm, P<0.001) and more than 20 years (normal, 28.2 cm and obese, 37.8 cm, P<0.001). Among those aged 8-17 years, high BP status was associated with a larger mean mid-AC (normotensive 26.1 cm vs. high BP 28.2 cm, P=0.001). Among adults aged 18 years and older, hypertension status was associated with a larger mean mid-AC (normotensive 32.4 cm vs. hypertensive 34.2 cm, P<0.001). Among those aged 12-19 years, 13.0% required a Baum large cuff (35-46.9 cm mid-AC) and 21.7% required a Welch Allyn large cuff (32-39.9 cm mid-AC). Among those aged more than 20 years, 33.2% required a Baum large cuff, 48.2% required a Welch Allyn large cuff, 1.3% required a Baum extra-large cuff (44-66 cm mid-AC), and 9.5% required a Welch Allyn extra-large cuff (40-55 cm mid-AC). CONCLUSION: Currently, BP is obtained in clinic, pharmacy, home, and ambulatory setting using single or multiple cuffs. National Health and Nutrition Examination Survey mid-AC data should be considered for accurate cuffing avoiding cuff hypertension or hypotension.

Fast Food Consumption Among Adults in the United States, 2013-2016.

Fast food is a part of the American diet and has been associated with high caloric intake (1), and poor diet quality (2). Time, financial resources, price, and availability influence fast food consumption (3). This report presents data on the percentage of adults who consumed fast food on a given day in the United States during 2013-2016.

Trends in hypertension prevalence, awareness, treatment, and control in older U.S. adults: data from the National Health and Nutrition Examination Survey 1988 to 2004.

OBJECTIVES: To describe hypertension trends in U.S. adults aged 60 and older using National Health and Nutrition Examination Survey (NHANES) data. SETTING: NHANES III (1988-1994) and NHANES 1999 to 2004. DESIGN: Cross-sectional nationally representative health examination survey. PARTICIPANTS: Participants in NHANES III (n=5,093) and NHANES 1999 to 2004 (n=4,710). MEASUREMENTS: Blood pressure (BP). RESULTS: In 1999 to 2004, 67% of U.S. adults aged 60 and older years were hypertensive, an increase of 10% from NHANES III. Between 1988 to 1994 and 1999 to 2004, hypertension control increased for men from 39% to 51% (P<.05) but remained unchanged for women (35% to 37%; P>.05). Non-Hispanic black men and women had higher prevalences of hypertension than non-Hispanic whites (odds ratio (OR)=2.54, 95% confidence interval (CI)=1.90-3.40 and OR=2.07, 95% CI=1.31-3.26, respectively), but men were less likely to have controlled BP (OR=0.60, 95% CI=0.41-0.86). Mexican-American men and women were less likely than non-Hispanic whites to have controlled BP (OR=0.55, 95% CI=0.33-0.91 and OR=0.63, 95% CI=0.40-0.98, respectively). Women and men aged 70 and older were significantly less likely to control their hypertension than those aged 60 to 69. In addition, women aged 70 and older were significantly less aware and treated. Having BP measured within 6 months was significantly associated with greater awareness, greater treatment in men and women, and greater control in women. A history of diabetes mellitus or chronic kidney disease (CKD) was significantly associated with less hypertension control. CONCLUSION: There was a significant increase in hypertension prevalence from 1988 to 2004. Hypertension control continues to be problematic for women, persons aged 70 and older, non-Hispanic blacks and Mexican Americans, and individuals with diabetes mellitus and CKD.

Prevalence of peripheral arterial disease and risk factors in persons aged 60 and older: data from the National Health and Nutrition Examination Survey 1999-2004.

OBJECTIVES: Peripheral arterial disease (PAD) is associated with significant cardiovascular morbidity and mortality. The study objectives were to examine the prevalence of PAD and associated risk factors. DESIGN: A cross-sectional nationally representative health examination survey. SETTING: The National Health and Nutrition Examination Survey 1999-2004. PARTICIPANTS: Data from 3,947 men and women aged 60 and older who received a lower extremity examination. MEASUREMENTS: The main outcome was PAD, defined as an ankle-brachial blood pressure index of less than 0.9 in either leg. RESULTS: In older U.S. adults, PAD prevalence was 12.2% (95% confidence interval (CI) = 10.9-13.5%). PAD prevalence increased with age. PAD prevalence was 7.0% (95% CI = 5.6-8.4%) for those aged 60 to 69, 12.5% (95% CI = 10.4-14.6%), and 23.2% (95% CI = 19.8-26.7%) for those aged 70 to 79 and 80 and older. Age-adjusted estimates show that non-Hispanic black men and women and Mexican-American women had a higher prevalence of PAD than non-Hispanic white men and women (19.2%, 95% CI = 13.7-24.6%; 19.3%, 95% CI = 13.3-25.2%; and 15.6%, 95% CI = 12.7-18.6%, respectively). The results of the fully adjusted model show that current smoking (OR = 5.48, 95% CI = 3.60-8.35), previous smoking (OR = 1.94, 95% CI = 1.39-2.69), diabetes mellitus (OR = 1.81, 95% CI = 1.12-2.91), low kidney function (OR = 2.69, 95% CI = 1.58-4.56), mildly decreased kidney function (OR = 1.71, 95% CI = 1.22-2.38), high-sensitivity C-reactive protein greater than 3.0 mg/L (OR = 2.69, 95% CI = 1.24-5.85), treated but not controlled hypertension (OR = 1.95, 95% CI = 1.40-2.72), and untreated hypertension (OR = 1.68, 95% CI = 1.13-2.50) were all significantly associated with prevalent PAD. CONCLUSION: PAD prevalence increases with age and is associated with treatable risk factors for cardiovascular disease.

Total, free, and percent free prostate-specific antigen levels among U.S. men, 2001-04.

OBJECTIVE: Screening for prostate cancer using prostate-specific antigen (PSA) tests is common but remains controversial. Total PSA using thresholds of 4.0 and 2.5 ng/mL has been used for screening men. In addition, the percent free PSA (free PSA/total PSA x 100%) using thresholds of less than 25% and 15% have been proposed for use in screening for prostate cancer in conjunction with the total PSA. The distributions of total PSA, free PSA, and percent free PSA, which vary with age and race-ethnicity among American men, would help determine the burden of screening using different thresholds of PSA tests. METHODS: PSA tests were performed on serum samples from men age 40 years and older (n = 2,546) who participated in the 2001-04 National Health and Nutrition Examination Survey (NHANES). Total, free and percent free PSA were estimated for Mexican American, non-Hispanic white, and non-Hispanic black men. RESULTS: About 6.2%, (95% confidence interval, 95% CI: 5.2-7.2%), corresponding to an estimated 3.6 million (95% CI: 3.0-4.2 million) men 40 years of age and older, had a total PSA of greater than or equal to 4.0 ng/mL. Approximately 3.6% (95% CI: 1.8-6.2%) of Mexican American men, 6.2% (95% CI: 5.1-7.6%) of non-Hispanic white men, and 7.8% (95% CI: 5.2-11.1 ) of non-Hispanic black men had total PSA of 4.0 ng/mL or more. Approximately 13.1 (95% CI: 11.7-14.5%) of men 40 years of age and older had total PSA greater than or equal to 2.5 ng/mL. For men with total PSA less than 2.5 ng/mL, 23.1% (95% CI: 21.0-25.3%) had a percent free PSA between 15% and 25%, and 5.0% had free PSA (95% CI: 3.9-6.4%) less than or equal to 15%. CONCLUSIONS: The effect of lowering the total PSA thresholds increases the number of U.S. men who would be referred for screening for prostate cancer. Total and free PSA increased with age in Mexican American, non-Hispanic white, and non-Hispanic black men. Information about the distribution of total, free, and percent free PSA will help guide public health policy in screening for prostate cancer.

Limitations of follicle-stimulating hormone in assessing menopause status: findings from the National Health and Nutrition Examination Survey (NHANES 1999-2000)*.

OBJECTIVE: We used data from the National Health and Nutrition Examination Survey (NHANES 1999-2000) to: establish new population-based estimates for follicle-stimulating hormone (FSH) and luteinizing hormone (LH); identify factors associated with FSH; and assess its efficacy in distinguishing among women in the reproductive, menopause transition, and postmenopausal stages. DESIGN: Nationally representative sample of 576 women aged 35 to 60 years examined during NHANES 1999-2000. RESULTS: Levels of FSH and LH increased significantly with reproductive stage. (Geometric mean FSH levels for successive stages: reproductive, 7.0 mIU/mL, SE 0.4; menopause transition, 21.9 mIU/mL, SE 3.7; and postmenopause, 45.7 mIU/mL, SE 4.3). There was considerable overlap, however, among distributions of FSH by stage. Only age and reproductive stage were significantly associated with FSH in multivariable analysis. FSH cutoff points between the reproductive and menopause transition stages [FSH = 13 mIU/mL, sensitivity 67.4% (95% CI 50.0-81.1), specificity 88.1% (95% CI 81.1-92.8)] and between the menopause transition and postmenopause stages [FSH = 45 mIU/mL, sensitivity 73.6% (95% CI 60.1-83.7), specificity 70.6% (95% CI 52.4-84.0)] were neither sensitive nor very specific. CONCLUSIONS: Age and reproductive stage are the most important determinants of FSH levels in US women; however, FSH by itself has limited utility in distinguishing among women in different reproductive stages.

Health characteristics of U.S. adults by body mass index category: results from NHANES 1999-2002.

OBJECTIVES: We examined self-reported health characteristics, health care utilization, activity patterns, and demographic characteristics of U.S. adults 20 years and over by body mass index (BMI) category. We hypothesized that overweight and obese adults would report fair/poor health more often, report more health provider visits annually, experience more joint pain, report greater limitations in their daily activities, and report more hours of sedentary leisure-time activity than normal-weight adults. METHODS: Self-reported health characteristics of U.S. adults from the National Health and Nutrition Examination Survey (NHANES) 1999-2002 were examined for three BMI categories: normal weight (BMI 18.5-24.9), overweight (BMI 25.0-29.9), and obese (BMI > or = 30.0). Covariates included gender, race/ethnicity, cigarette smoking, and educational attainment. We examined BMI group differences using descriptive and regression methods. RESULTS: Compared to normal-weight individuals, overweight individuals reported fair/poor health more often, more limitations in daily activities, and more health provider contacts. Overweight and obese subjects reported more hours of television watching and video game use compared to normal-weight subjects. CONCLUSION: Our findings are useful to describe the health characteristics of U.S. adults and may be used to anticipate future demand for health services and to support intervention programs that help individuals achieve desirable weight status.

Total, free, and complexed prostate-specific antigen levels among US men, 2007-2010.

BACKGROUND: Screening for prostate cancer using prostate-specific antigen (PSA) is common. Prostate cancer has been associated with higher total PSA (tPSA), lower free PSA (fPSA), lower percent free PSA (%fPSA), and higher complexed PSA (cPSA). METHODS: Total, free and complexed PSAs were performed on 3251 men ≥40years in the 2007-2010 National Health and Nutrition Examination Survey. Distributions of the PSA tests were examined by age, race and ethnicity, and body mass index (BMI) groups. Percentages of men at PSA thresholds were examined. RESULTS: Total PSA geometric mean was 0.96µg/l among men aged ≥40years and increased from 0.74µg/l for men 40-49years, to 1.82µg/l for men 80years and older. Non-Hispanic Whites had lower age-adjusted mean tPSA (1.03µg/l) and cPSA (0.56µg/l) than non-Hispanic Blacks (tPSA 1.25µg/l and cPSA 0.72µg/l). Obese men had lower age-adjusted mean total, free and complexed PSAs (0.94, 0.27, and 0.51µg/l, respectively) than men with normal BMI (tPSA 1.21, fPSA 0.32, and cPSA 0.68µg/l, respectively). CONCLUSION: Total, free and complexed PSAs increased with age; tPSA and cPSAs were highest in non-Hispanic Blacks; and total, free, and complexed PSAs were lowest in obese men.