Nutrition Examination Survey Epidemiologic Follow-up Research Articles

The interaction between stress and positive affect in predicting mortality

ObjectivePositive affect is associated with longevity; according to the stress-buffering hypothesis, this is because positive affect reduces the health harming effects of psychological stress. If this mechanism plays a role, then the association between positive affect and mortality risk should be most apparent among individuals who report higher stress. Here, we test this hypothesis. MethodsThe sample consisted of 8542 participants aged 32–86 from the National Health and Nutrition Examination Survey (NHANES I) Epidemiological Follow-up Study (NHEFS). We used Cox's proportional hazards regression to test for the main effects of and the interaction between positive affect and perceived stress in predicting mortality risk over a 10year follow up period. ResultsGreater positive affect was associated with lower mortality risk. We found a significant interaction between positive affect and perceived stress such that the association between positive affect and mortality risk was stronger in people reporting higher stress. In the fully adjusted model, a standard deviation increase in positive affect was associated with a 16% (HR=0.84; 95% CI=0.75, 0.95) reduction in mortality risk among participants who reported high levels of stress. The association between positive affect and mortality risk was weaker and not significant among participants who reported low levels of stress (HR=0.98; 95% CI=0.89, 1.08). ConclusionOur results support the stress-buffering model and illustrate that the association between positive affect and reduced risk may be strongest under challenging circumstances.

Abstract P146: Serum Magnesium and Mortality in the General US Population: Results From the NHANES I Epidemiologic Follow-up Study

Introduction: Low magnesium (Mg) intake and/or status has been associated with increased risk of chronic disease, including cardiovascular disease (CVD) and cancer. However, whether and to what extent low serum Mg levels are associated with all-cause or cause-specific mortality in the general population is uncertain. Hypothesis: We aimed to quantify the dose-response associations between low concentrations of serum Mg and mortality from all causes, cancer, CVD, and stroke in the general US population. Methods: We analyzed prospective data on 14,353 participants aged 25-74 years with baseline measures of serum Mg concentrations from the National Health and Nutrition Examination Survey Epidemiologic Follow-up Study 1971-2006. We estimated the mortality hazard ratios (HRs) for participants within predefined and clinically meaningful categories of serum Mg levels, including <0.7, 0.7-0.74, 0.75-0.79, 0.8-0.9 (normal reference), 0.9-0.94, 0.95-0.99, and ≥1.0 mmol/L, using Cox proportional hazards models. Restricted cubic spline models were applied to examine potentially nonlinear relationships between serum Mg and mortality. Results: During a mean follow-up of 27.6 years, 7,072 deaths occurred, 3,310 (47%) CVD deaths, 1,533 (22%) cancer deaths, and 281 (4%) stroke deaths. Twenty-one percent of all participants had low levels of serum Mg (<0.8 mmol/L) and 1.5% had extremely low serum Mg (<0.7 mmol/L). Age-adjusted all-cause mortality rates were 3845, 3491, 3471, 3400 (normal reference), 3531, 3525, and 3836 per 100,000 person-years for increasing categories of serum Mg; the HRs and 95% confidence intervals for increasing serum Mg were 1.32 (1.02-1.72), 0.93 (0.74-1.16), and 1.06 (0.96-1.18), 1.07 (0.97-1.18), 0.94 (0.77-1.13), and 0.93 (0.72-1.21), compared to the reference group (0.8-0.9 mmol/L). An L-shaped association between serum Mg concentrations and all-cause mortality was observed after adjusting for potential confounders (Figure). No statistically significant associations were observed between serum Mg and cancer, CVD, or stroke mortality. Conclusions: Very low serum Mg levels were significantly associated with all-cause mortality in the general US population. Our findings support the hypothesis that Mg deficiency as defined by very low serum Mg may have an important influence on mortality.

Male Pattern Baldness in Relation to Prostate Cancer-Specific Mortality: A Prospective Analysis in the NHANES I Epidemiologic Follow-up Study.

We used male pattern baldness as a proxy for long-term androgen exposure and investigated the association of dermatologist-assessed hair loss with prostate cancer-specific mortality in the first National Health and Nutrition Examination Survey Epidemiologic Follow-up Study. From the baseline survey (1971-1974), we included 4,316 men who were 25-74 years of age and had no prior cancer diagnosis. We estimated hazard ratios and used Cox proportional hazards regressions with age as the time metric and baseline hazard stratified by baseline age. A hybrid framework was used to account for stratification and clustering of the sample design, with adjustment for the variables used to calculate sample weights. During follow-up (median, 21 years), 3,284 deaths occurred; prostate cancer was the underlying cause of 107. In multivariable models, compared with no balding, any baldness was associated with a 56% higher risk of fatal prostate cancer (hazard ratio = 1.56; 95% confidence interval: 1.02, 2.37), and moderate balding specifically was associated with an 83% higher risk (hazard ratio = 1.83; 95% confidence interval: 1.15, 2.92). Conversely, patterned hair loss was not statistically significantly associated with all-cause mortality. Our analysis suggests that patterned hair loss is associated with a higher risk of fatal prostate cancer and supports the hypothesis of overlapping pathophysiological mechanisms.

Transformation Models for Survival Data Analysis with Applications

When the event of interest never occurs for a proportion of subjects during the study period, survival models with a cure fraction are more appropriate in analyzing this type of data. Considering the non-linear relationship between response variable and covariates, we propose a class of generalized transformation models motivated by Zeng et al. [1] transformed proportional time cure model, in which fractional polynomials are used instead of the simple linear combination of the covariates. Statistical properties of the proposed models are investigated, including identifiability of the parameters, asymptotic consistency, and asymptotic normality of the estimated regression coefficients. A simulation study is carried out to examine the performance of the power selection procedure. The generalized transformation cure rate models are applied to the First National Health and Nutrition Examination Survey Epidemiologic Follow-up Study (NHANES1) for the purpose of examining the relationship between survival time of patients and several risk factors.

Total White Blood Cell Count, Absolute Neutrophil Count, Absolute Lymphocyte Count, Neutrophil-to-Lymphocyte Ratio and the Risk of Breast Cancer: The NHANES I Epidemiologic Follow-up Study

The purpose of this study was to examine total white blood cell count (TWBCC), absolute neutrophil count (ANC), absolute lymphocyte count (ALC), and neutrophil-to-lymphocyte ratio’s (NLR) association with the risk of incident breast cancer (BCa). A prospective analysis was conducted among a cohort of 2,873 women from the First National Health and Nutrition Examination Survey (NHANES I) Epidemiologic Follow-up Study. In the present analysis, the association found between lower ALC and increased BCa risk was no longer statistically significant after adjusting for age. Additionally, no statically significant associations were found between any level of ANC, NLR, and TWBCC with incident BCa. Therefore, additional studies, which address the limitations encountered in the present analysis, are needed to validate, or rule out, their use as biomarkers of BCa risk in women.

Positive psychological health and stroke risk: The benefits of emotional vitality.

Stroke is a leading cause of death and disability. Various forms of positive psychological health (e.g., emotional vitality) are associated with lower risk for heart disease. However, it is unclear whether positive psychological health may also be beneficial for stroke risk. The purpose of the present study was to examine prospectively the association between emotional vitality and incident stroke in a nationally representative sample of 6,019 participants in the first National Health and Nutrition Examination Survey Epidemiologic Follow-up Study. Emotional vitality was assessed via self-report at study baseline in 1971-1975. Stroke cases were identified from hospital/nursing home discharge reports and death certificates. Multivariate Cox proportional hazards regression models were used to estimate hazard ratios and 95% confidence intervals of incident stroke associated with a 1 SD increase in emotional vitality scores. Models were adjusted for traditional cardiovascular disease risk factors and subsequently for psychological distress. Higher emotional vitality was associated with lower risk of incident stroke over a mean of 16.29 (SD = 4.75) years of follow-up (hazard ratio = 0.89; 95% confidence interval: 0.81, 0.99). Findings persisted when controlling for traditional cardiovascular disease risk factors and psychological distress. Higher levels of emotional vitality were prospectively associated with lower stroke risk in a representative sample of the U.S. Associations were independent of psychological distress. Results point to the potential importance of positive psychological functioning for cardiovascular health and for stroke prevention. (PsycINFO Database Record

Personality and diabetes mellitus incidence in a national sample

ObjectiveTo test whether personality traits were prospectively associated with type 2 diabetes incidence. MethodsThe sample (n=6798) was derived from the National Health and Nutrition Examination Survey Epidemiological Follow-up Study cohort. We fit four logistic regression models to test whether neuroticism, extraversion, openness to experience, or the Type A behavior pattern predicted type 2 diabetes incidence. Model 1 included sex, age, and race/ethnicity. Model 2 added personality traits, Model 3 added depressive symptoms, and Model 4 added body mass index (BMI), hypertension, and cigarette smoking status as predictors. ResultsIn Model 1 age was associated with increased risk of diabetes (2% per year); being black as opposed to white was associated with a three-fold increase in risk. In Model 2 age and being black were still significant and extraversion was associated with decreased risk (17% per standard deviation [SD]). In Model 3 age, being black, and extraversion were still significant. In addition, neuroticism was associated with decreased risk (26% per SD) and depressive symptoms were associated with increased risk (28% per SD). In Model 4 age, being black, neuroticism, and depressive symptoms were still significant. BMI was associated with increased risk (14% per SD) and extraversion was no longer significant. ConclusionsHigher neuroticism was associated with reduced type 2 diabetes risk even after controlling for race/ethnicity, age, depressive symptoms, and BMI. Extraversion and Type A behavior were not significant after including covariates.

Nutritional risk factors for tuberculosis among adults in the United States, 1971-1992.

The risk of developing tuberculosis (TB) may be related to nutritional status. To determine the impact of nutritional status on TB incidence, the authors analyzed data from the First National Health and Nutrition Examination Survey (NHANES I) Epidemiologic Follow-up Study (NHEFS). NHANES I collected information on a probability sample of the US population in 1971-1975. Adults were followed up in 1982-1992. Incident TB cases were ascertained through interviews, medical records, and death certificates. TB incidences were compared across different levels of nutritional status after controlling for potential confounding using proportional hazards regression appropriate to the complex sample design. TB incidence among adults with normal body mass index was 24.7 per 100,000 person-years (95% confidence interval (CI): 13.0, 36.3). In contrast, among persons who were underweight, overweight, and obese, estimated TB incidence rates were 260.2 (95% CI: 98.6, 421.8), 8.9 (95% CI: 2.2, 15.6), and 5.1 (95% CI: 0.0, 10.5) per 100,000 person-years, respectively. Adjusted hazard ratios were 12.43 (95% CI: 5.75, 26.95), 0.28 (95% CI: 0.13, 0.63), and 0.20 (95% CI: 0.07, 0.62), respectively, after controlling for demographic, socioeconomic, and medical characteristics. A low serum albumin level also increased the risk of TB, but low vitamin A, thiamine, riboflavin, and iron status did not. A population's nutritional profile is an important determinant of its TB incidence.

Vitamin D Intake and Cardiovascular Mortality in the NHANES I Epidemiological Follow-Up Study Cohort

ABSTRACTThe objective of the present study was to determine whether vitamin D intake is associated with CVD mortality in a general population sample. The association between vitamin D intake and CVD mortality (ICD-9 code 410–414) rates was investigated using data from the the First National Health and Nutrition Examination Survey (NHANES I) Epidemiological Follow-up Study (NHEFS) 1971–1992. Overall, higher vitamin D intake was associated with lower CVD mortality. After adjustment for traditional risk factors for CVD, vitamin D intake showed mild but nonstatistically significant protective effects against CVD mortality with a hazard ratio for adequate as compared to low intake (with 95% confidence intervals) of 0.90 (0.74, 1.08). Hazard ratios were 0.95, 0.83, 0.88, and 1.02, in males, females, Whites, and Blacks, respectively (with 95% confidence intervals overlapping 1.0 in all cases). Thus, we did not find a statistically significant association between vitamin D intake and CVD mortality, although our findings are compatible with a mild protective effect, especially among females and Whites.

Actinic Skin Damage and Mortality - the First National Health and Nutrition Examination Survey Epidemiologic Follow-up Study

BackgroundExposure to sunlight may decrease the risk of several diseases through the synthesis of vitamin D, whereas solar radiation is the main cause of some skin and eye diseases. However, to the best of our knowledge, the association of sun-induced skin damage with mortality remains unknown.Methodology/Principal FindingsSubjects were 8472 white participants aged 25–74 years in the First National Health and Nutrition Examination Survey Epidemiologic Follow-up Study. Cardiovascular disease mortality, cancer mortality, and all-cause mortality were obtained by either a death certificate or a proxy interview, or both. Actinic skin damage was examined and recorded by the presence and severity (absent, minimal, moderate, or severe) of overall actinic skin damage and its components (i.e., fine telangiectasia, solar elastosis, and actinic keratoses). Cox regression and Kaplan-Meier methods were applied to explore the associations. A total of 672 cancer deaths, 1500 cardiovascular disease deaths, and 2969 deaths from all causes were documented through the follow-up between 1971 and 1992. After controlling for potential confounding variables, severe overall actinic skin damage was associated with a 45% higher risk for all-cause mortality (95% CI: 1.22, 1.72; P<0.001), moderate overall skin damage with a 20% higher risk (95% CI: 1.08., 1.32; P<0.001), and minimal overall skin damage with no significant mortality difference, when compared to those with no skin damage. Similar results were obtained for all-cause mortality with fine telangiectasia, solar elastosis, and actinic keratoses. The results were similar for cancer and cardiovascular disease mortality.ConclusionsThe present study gives an indication of an association of actinic skin damage with cardiovascular disease, cancer and all-cause mortality in white subjects. Given the lack of support in the scientific literature and potential unmeasured confounding factors, this finding should be interpreted with caution. More independent studies are needed before any practical recommendations can be made.

Section 5: Management of Asymptomatic Patients with Reduced Left Ventricular Ejection Fraction

Section 5: Management of Asymptomatic Patients with Reduced Left Ventricular Ejection Fraction

Light to Moderate Alcohol Consumption and Disability: Variable Benefits by Health Status

In adults, light to moderate alcohol consumption is associated with lower risks for heart disease, diabetes, and mortality. This study examined whether light to moderate alcohol use is also associated with lower risk of incident physical disability over two 5-year periods in 4,276 noninstitutionalized adults in the United States, aged 50 years or older, by using data from 3 waves of the National Health and Nutrition Examination Survey Epidemiologic Follow-up Study surveys from 1982 to 1992. Light/moderate drinking (<15 drinks per week and <5 per drinking day or 4 per drinking day for women) was associated with reduced risk for incident disability or death over 5 years, compared with abstention (adjusted odds ratio = 0.77; P = 0.008). Among survivors, light/moderate drinking was associated with lower risk for incident disability, compared with abstention (adjusted odds ratio = 0.75; P = 0.009). In stratified analyses, disability risk decreased with light/moderate drinking in a dose-dependent fashion in men and women with good or better self-reported health but not in men or women with fair or worse self-reported health. Alcohol consumption in moderation might reduce the risk of developing physical disability in older adults in good health but not in those in poor health.

Long-term Obesity and Avoidable Hospitalization Among Younger, Middle-aged, and Older Adults

Avoidable hospitalizations are considered to result from conditions that are preventable with timely and effective ambulatory care. We examined whether obesity, particularly long-term obesity, is associated with risk for and frequency of avoidable hospital stays. Data were drawn from the First National Health and Nutrition Examination Survey Epidemiological Follow-up Survey, a 20-year study of adults aged 25 to 74 years (N = 6833). Using measures of body mass index (BMI) (calculated as weight in kilograms divided by height in meters squared) at baseline and at 25 years of age, we estimated the effect of obesity (BMI > or =30.0) on avoidable hospitalization risk using Cox proportional hazards models, and we estimated its influence on the rate of avoidable stays per year using interval regression models. All multivariate analyses were adjusted for morbidity and other covariates. One thousand twenty-three subjects experienced a hospitalization considered avoidable. Compared with normal-weight subjects, the adjusted hazard ratio of an avoidable stay among obese subjects was 1.82 (95% confidence interval [CI], 1.31-2.51) for those aged 25 to 44 years, 1.29 (95% CI, 1.05-1.59) for those aged 45 to 64 years, and 1.46 (95% CI, 1.23-1.74) for those 65 years and older. Among participants aged 45 to 64 years at baseline, obesity at 25 years of age was strongly associated with both the risk (hazard ratio, 1.91; 95% CI, 1.59-2.29) and frequency (beta coefficient, 0.057; SE, 0.018) of avoidable stays when accounting for baseline BMI category and additional covariates. For subjects 65 years and older, obesity at 25 years of age was associated with increased risk of avoidable hospitalization (hazard ratio, 1.87; 95% CI, 1.14-3.08) and with increased frequency of such admissions (beta coefficient, 0.138; SE, 0.038). As indicated by its association with avoidable hospitalizations, long-term obesity is a substantial risk for complications in medical care. Interventions should target obesity early in the life course to help improve lifelong delivery of ambulatory care and to reduce strains on health care resources.

Caffeinated beverage intake and the risk of heart disease mortality in the elderly: a prospective analysis

Background:Motivated by the possibility that caffeine could ameliorate the effect of postprandial hypotension on a high risk of coronary events and mortality in aging, we hypothesized that caffeinated beverage consumption decreases the risk of cardiovascular disease (CVD) mortality in the elderly.Objective:The objective of the study was to use prospective cohort study data to test whether the consumption of caffeinated beverages exhibits this protective effect.Design:Cox regression analyses were conducted for 426 CVD deaths that occurred during an 8.8-y follow-up in the prospective first National Health and Nutrition Examination Survey Epidemiologic Follow-up Study. The analysis involved 6594 participants aged 32–86 y with no history of CVD at baseline.Results:Participants aged ≥65 y with higher caffeinated beverage intake exhibited lower relative risk of CVD and heart disease mortality than did participants with lower caffeinated beverage intake. It was a dose-response protective effect: the relative risk (95% CI) for heart disease mortality was 1.00 (referent), 0.77 (0.54, 1.10), 0.68 (0.49, 0.94), and 0.47 (0.32, 0.69) for <0.5, 0.5–2, 2–4, and ≥4 servings/d, respectively (Pfor trend = 0.003). A similar protective effect was found for caffeine intake in mg/d. The protective effective was found only in participants who were not severely hypertensive. No significant protective effect was found in participants aged <65 y or in cerebrovascular disease mortality for those aged ≥65 y.Conclusion:Habitual intake of caffeinated beverages provided protection against the risk of heart disease mortality among elderly participants in this prospective epidemiologic analysis.

Are Blood Pressure Predictors of Cardiovascular Disease Mortality Different for Prehypertensives Than for Hypertensives?

The ability of diastolic, systolic, mean arterial, and pulse pressures to predict cardiovascular disease (CVD) morality has not been assessed for persons with prehypertension (diastolic pressure 80 to 89 mm Hg or systolic pressure 120 to 139 mm Hg). Cox's regression analyses were conducted using 4849 subjects aged 33 to 87 years from the First National Health and Nutrition Examination Survey Epidemiologic Follow-up Study. A correction was made for the regression-dilution bias. There were 327 cardiovascular disease and 258 coronary heart-disease deaths during an average follow-up of 8.6 years. For nonelderly prehypertensives, systolic blood pressure (BP) was a stronger predictor than diastolic BP. The multivariate single predictor hazard ratios (95% confidence interval) for CVD mortality were 1.43 (0.65-3.14) and 2.11 (1.28-3.49), for a 10 mm Hg increment diastolic and systolic BP, respectively. For elderly prehypertensives, it was reversed. The equivalent results were 1.53 (1.10-2.13) and 1.25 (0.89-1.60), respectively. For nonelderly hypertensives, diastolic BP was a stronger predictor than systolic BP, and for elderly hypertensives it was reversed. Diastolic and systolic BP provided as much as or more predictive information than pulse and mean arterial pressure in all analyses. For nonelderly prehypertensives, systolic BP was the strongest predictor, whereas for hypertensives the strongest predictor was diastolic BP. For elderly subjects this pattern was reversed.

Section 5: Management of Asymptomatic Patients With Reduced Left Ventricular Ejection Fraction

Section 5: Management of Asymptomatic Patients With Reduced Left Ventricular Ejection Fraction

Building prediction models for coronary heart disease by synthesizing multiple longitudinal research findings

No methodology is currently available to allow the combining of individual risk factor information derived from different longitudinal studies for a chronic disease in a multivariate fashion. This paper introduces such a methodology, named Synthesis Analysis, which is essentially a multivariate meta-analytic technique. The construction and validation of statistical models using available data sets. Two analyses are presented. (1) With the same data, Synthesis Analysis produced a similar prediction model to the conventional regression approach when using the same risk variables. Synthesis Analysis produced better prediction models when additional risk variables were added. (2) A four-variable empirical logistic model for death from coronary heart disease was developed with data from the Framingham Heart Study. A synthesized prediction model with five new variables added to this empirical model was developed using Synthesis Analysis and literature information. This model was then compared with the four-variable empirical model using the first National Health and Nutrition Examination Survey (NHANES I) Epidemiologic Follow-up Study data set. The synthesized model had significantly improved predictive power (chi = 43.8, P<0.00001). Synthesis Analysis provides a new means of developing complex disease predictive models from the medical literature.

The Relationship Between Reduced Lung Function and Cardiovascular Mortality: A Population-Based Study and a Systematic Review of the Literature

Conditions that give rise to reduced lung function are frequently associated with low-grade systemic inflammation, which may lead to poor cardiovascular outcomes. We sought to determine the relationship between reduced FEV1 and cardiovascular mortality, independent of smoking. Longitudinal population-based study and a meta-analysis of literature. Representative sample of the general population. Participants of the first National Health and Nutrition Examination Survey Epidemiologic Follow-up Study who were 40 to 60 years of age at baseline assessment (n = 1,861). We compared the risk of cardiovascular mortality across quintiles of FEV1. Individuals in the lowest FEV1 quintile had the highest risk of cardiovascular mortality (relative risk [RR], 3.36; 95% confidence interval [CI], 1.54 to 7.34). Compared to FEV1 quintile 1, individuals in quintile 5 had a fivefold increase in the risk of death from ischemic heart disease (RR, 5.65; 95% CI, 2.26 to 14.13). We also performed a systematic review of large cohort studies (> 500 participants) that reported on the relationship between FEV1 and cardiovascular mortality (12 studies; n = 83,880 participants). Compared to participants in the highest FEV1 category, those with reduced FEV1 had a higher risk of cardiovascular mortality (pooled RR, 1.77; 95% CI, 1.56 to 1.97). There is strong epidemiologic evidence to indicate that reduced FEV1 is a marker for cardiovascular mortality independent of age, gender, and smoking history.

Length of hospital stays among obese individuals.

We examined lengths of hospital stay among individuals categorized according to weight status. We used data from the First National Health and Nutrition Examination Survey Epidemiologic Followup Survey to estimate length-of-stay differences. Individuals with body mass indexes (BMIs) of 35 kg/m2 or above, those with BMIs of 30 to 34 kg/m2, and those with BMIs of 25 to 29 kg/m2 had crude length-of-stay rates greater than those of normal-weight individuals. Association between BMI and length of stay varied over time. Obese individuals experience longer hospital stays than normal-weight individuals.

In Sickness but Not in Health: Self-ratings, Identity, and Mortality

Self-rated health as a predictor of mortality has been studied primarily in large, representative populations, with relatively little progress toward understanding the information processing that individuals use to arrive at these ratings. With subsamples of National Health and Nutrition Examination Survey (NHANES) Epidemiologic Follow-up Study (NHEFS) data for respondents with circulatory system disease (N = 3,709) and respondents with no diagnosable disorders (N = 1,127) at baseline, we test the idea that individuals with experience of chronic disease of the circulatory system will have more predictive self-ratings of health than healthy individuals. Poor or fair self-rated health increased the adjusted hazard of all-cause mortality for respondents with circulatory system disease, but not for respondents who were healthy. Additional analyses confirm that poor or fair self-rated health is particularly predictive for respondents with self-reported history of circulatory system diagnoses and perception of symptoms, but not for respondents without symptoms or diagnoses prior to the NHANES physical exam.