Functional regression with intensively measured longitudinal outcomes: a new lens through data partitioning

(1) To present hearing threshold data from a recent nationally representative survey in the United States (National Health and Nutrition Examination Survey, 1999-2004) in a distributional format that might be appropriate to replace Annex B in international (ISO-1999) and national (ANSI S3.44) standards and (2) to compare these recent data with older survey data (National Health Examination Survey I, 1959-1962) on which the current Annex B is based. Better-ear threshold distributions (selected percentiles and their confidence intervals) were estimated using linear interpolation. The 95% confidence intervals for the medians for the two surveys were compared graphically for each of the four age groups and for both men and women. In addition, we calculated odds ratios comparing the prevalences of better-ear hearing impairment (thresholds > 25 dB HL) between the two surveys, for 500, 1000, 2000, and 4000 Hz, and for their four-frequency average. Across age and sex groups, median thresholds were lower (better) in the 1999-2004 survey at 500, 3000, 4000, and 6000 Hz (8000 Hz was not tested in the 1959-1962 survey). For both men and women, the prevalence of hearing impairment was significantly lower in 1999-2004 at 500, 2000, and 4000 Hz, but not at 1000 Hz. For men and women of a specific age, high-frequency hearing thresholds were lower (better) in 1999-2004 than in 1959-1962. The prevalences of hearing impairment were also lower in the recent survey. Differences seen at 500 Hz may be attributable at least in part to changes in standards for ambient noise in audiometry. The National Health and Nutrition Examination Survey 1999-2004 distributions are offered as a possible replacement for Annex B in ISO-1999 and ANSI S3.44.

Epidemiology of latex sensitization

Calibration of Cystatin C in the National Health and Nutrition Examination Surveys (NHANES)

Contribution of metabolic factors to alanine aminotransferase activity in persons with other causes of liver disease

Abdominal adiposity in U.S. adults: prevalence and trends, 1960–2000

Bone Marrow Iron in CKD: Correlation With Functional Iron Deficiency

Effects of Sex and Postmenopausal Estrogen Use on Serum Phosphorus Levels: A Cross-sectional Study of the National Health and Nutrition Examination Survey (NHANES) 2003-2006

Less Hidden Celiac Disease But Increased Gluten Avoidance Without a Diagnosis in the United States: Findings From the National Health and Nutrition Examination Surveys From 2009 to 2014

This study aimed to investigate the factors influencing the decision on whether to receive regular oral check-ups among the national health insurance beneficiaries with income and aged over 20 years in Korea. This was a cross-sectional study, using the data from the 2014 6th Korea National Health and Nutrition Examination Survey (KNHANES VI-2), conducted by the Korea Centers for Disease Control and Prevention. The final sample included 2,843 subjects who participated in the health examination survey and oral check-ups. The IBM SPSS Statistics ver. 20.0 was used for the statistical analysis, based on the complex sampling design. The Rao-Scott chi-square test was used to verify the difference in the distribution of independent variables with regard to oral check-ups. The binary logistic regression analysis was used to determine the influencing factors. The ratio of beneficiaries who received oral check-ups was less than half of those who received medical examinations. The Rao-Scott chi-square test, revealed significant differences in the age group (p<0.05) of the predisposing factors, toothache within a year (p<0.001), untreated dental caries (p<0.001) of the need factors, personal income level (p<0.001), educational level (p<0.001), type of medical insurance (p<0.001), and private health insurance (p<0.01) of the enabling factors. In the binary logistic regression analysis, factors influencing oral check-ups were age group, personal income level, educational level, toothache within a year, and untreated dental caries. These findings show a variety of factors influencing the utilization of regular oral check-ups.

Physical activity is well-established on the cancer survivorship research agenda, but prostate cancer survivors remain an understudied population. Additionally, the unique relationships between sedentary time and health outcomes have not yet been considered in this group. We examined the associations of accelerometer-assessed physical activity and sedentary time with waist circumference in 103 prostate cancer survivors from the National Health and Nutrition Examination Survey 2003-2004 and 2005-2006. Participants wore an Actigraph accelerometer for 7 days, and activity levels were summarised as moderate-to-vigorous intensity activity (accelerometer counts/minute ≥ 1952), light-intensity activity (counts/minute 100-1951) and sedentary time (counts/minute < 100). Moderate-to-vigorous intensity physical activity was inversely associated with waist circumference (β=-6.728, 95% CI: -12.267, -1.190, P= 0.020), equating to a top versus bottom quartile difference of 13.7 cm. No discernable relationship existed between light-intensity activity or sedentary time and adiposity. This is the first study to objectively measure the activity levels of prostate cancer survivors. Increasing moderate-to-vigorous activity may assist this population with weight management. More research into the relationships of light-intensity physical activity and sedentary behaviour with health outcomes among prostate cancer survivors is warranted, given the strong relationships seen in the broader population.

Re: The Co-Occurring Syndrome—Coexisting Erectile Dysfunction and Benign Prostatic Hyperplasia and Their Clinical Correlates in Aging Men: Results from the National Health and Nutrition Examination Survey

Potential conflict of interest: Nothing to report. To the Editor: Hepatitis delta virus (HDV) is a defective RNA virus requiring acute or chronic hepatitis B viral coinfection.1 The prevalence of HDV in the US general population is currently unknown, though a relatively high seroprevalence of 3.4% was reported among hepatitis B surface antigen‐positive US veterans.2 Previous small studies involving hepatitis B surface antigen‐positive patients have also revealed high HDV prevalence rates among injection drug users (11%), hemophiliacs (19%), and men who have sex with men (2%).3 We used National Health and Nutrition Examination Survey data (1999‐2012) to obtain estimates of HDV prevalence for the US population using weighted samples. In the National Health and Nutrition Examination Survey, the test for antibody to HDV is performed on participants with a positive test for hepatitis B core antibody and hepatitis B surface antigen. We calculated sample proportions to determine HDV period prevalence. We stratified estimates by gender, race, human immunodeficiency virus hepatitis C virus coinfections, injection drug use, and sexual behavior. From 1999 to 2012, data on 71,916 individuals were obtained, with 52,209 (72.6%) receiving HDV testing. The overall prevalence of HDV in the United States was 0.02% (10/52209), with a mean age of 52.1 ± 14.0 years and 60% males. Table 1 summarizes our results. Table 1 - Patient Demographics and Clinical Characteristics Stratified by HDV Status Variable HDV‐Negative, % (n = 52,199) HDV‐Positive (%) (n = 10) P Mean age, years (SD) 36.6 (23.01) 52.1 (14.01) 0.02 Sex Male 49.2 60.0 0.54 Female 50.8 40.0 Race/ethnicity Mexican American 23.3 10.0 0.01 Other Hispanic 7.1 0 Non‐Hispanic white 40.3 10.0 Non‐Hispanic black 23.3 50.0 Other race, including multiracial 6.0 30.0 HCV antibody Positive 1.2 20 0.08 Negative 98.8 80 HIV status Positive 0.5 20 0.03 Negative 99.5 80 Injection drug use Yes 2.8 0 0.99 No 97.2 100 Homosexual men Yes 5.2 25 0.19 No 94.8 75 Fisher's exact test was used for categorical variables and the Mann‐Whitney test for continuous variables.Abbreviations: HCV, hepatitis C virus; HIV, human immunodeficiency virus; SD, standard deviation. The prevalence of HDV in the United States is significantly lower than previously reported. Compared to veteran population estimates, the prevalence of HDV is more than 100‐fold less common among the civilian US population with chronic hepatitis B infection. This study is limited by the likelihood of this data set to underestimate the true prevalence owing to exclusion of high‐risk populations such as the homeless, incarcerated, and institutionalized, in whom high‐risk characteristics (e.g., injection drug use) are overrepresented. Despite these limitations, this study represents the first report attempting to establish an estimate of the prevalence of HDV in the general US population. Routine screening for HDV in hepatitis B virus‐infected patients and the general population is not presently supported by available evidence, although future research will be required to further define key at‐risk populations for whom risk factor‐based testing may be indicated.

Heart Disease and Stroke Statistics—2009 Update

BackgroundThere is controversy regarding the relationship between serum iron levels and atherosclerotic cardiovascular disease (ASCVD).ObjectiveTo investigate the relationship between serum iron levels and ASCVD among older adults using data from the 2009–2018 National Health and Nutrition Examination Survey (NHANES).MethodsWe performed a cross-sectional analysis involving 8,682 participants aged 60 years and older, with complete data on serum iron levels and confirmed ASCVD status, sourced from the 2009–2018 National Health and Nutrition Examination Survey (NHANES). Multivariable logistic regression models were used to examine the association between serum iron levels and ASCVD. To assess the consistency of this association across different demographic groups, subgroup analyses, and interaction tests were performed.ResultsThe group with the highest serum iron levels (fourth quartile, 100–369 μg/dL) exhibited several distinct characteristics: they were the youngest on average (69.57 ± 6.91 years), had the highest proportion of males (61.42%), and the highest hemoglobin levels (14.43 ± 1.33 g/dL). This group also showed the lowest iron supplement usage (19.71 ± 12.85 mg/30 days), white blood cell counts (6.73 ± 2.41 1,000 cells/μL), and serum creatinine levels (0.98 ± 0.45 mg/dL). Moreover, they had higher levels of education and income, a higher likelihood of being married, and a lower body mass index (BMI). Additionally, they had significantly lower rates of diabetes, hypertension, stroke, and heart attacks (all p < 0.05). After adjusting for potential confounders, a linear relationship between serum iron levels and ASCVD was initially observed (OR = 0.97; 95% CI, 0.95–0.99, p < 0.05). However, further analysis using a two-part logistic regression model with an inflection point at 131 μg/dL revealed more nuanced results. For serum iron levels below 131 μg/dL, each 10 μg/dL increase was associated with a 4% decrease in the odds of ASCVD (OR = 0.96; 95% CI, 0.93–0.98, p < 0.001). Conversely, for serum iron levels above 131 μg/dL, each 10 μg/dL increase corresponded to a 1% increase in the odds of ASCVD, though this finding was not statistically significant (OR = 1.01; 95% CI, 0.98–1.08, p > 0.05).ConclusionIn the US elderly population, serum iron levels are negatively associated with ASCVD, particularly when serum iron levels are below 131 μg/dL.

Depression is a risk factor for traumatic brain injury: Evidence from the National Health and Nutrition Examination Survey and Mendelian randomization analysis.