Weight loss from maximum body weight and mortality: the Third National Health and Nutrition Examination Survey Linked Mortality File.

OBJECTIVE: The aim of this longitudinal study is to examine the relationship between weight loss from maximum body weight, body mass index (BMI), and mortality in a nationally representative sample of men and women. DESIGN: Longitudinal cohort study. SUBJECTS: In all, 6117 whites, blacks, and Mexican-Americans 50 years and over at baseline who survived at least 3 years of follow-up, from the Third National Health and Nutrition Examination Survey Linked Mortality Files (1988-1994 with passive mortality follow-up through 2000), were included. MEASUREMENTS: Measured body weight and self-reported maximum body weight obtained at baseline. Weight loss (maximum body weight minus baseline weight) was categorized as <5%, 5-<15%, and >or=15%. Maximum BMI (reported maximum weight (kg)/measured baseline height (m)(2)) was categorized as healthy weight (18.5-24.9), overweight (25.0-29.9), and obese (>or=30.0). RESULTS: In all, 1602 deaths were identified. After adjusting for age, race, smoking, health status, and preexisting illness, overweight men with weight loss of 15% or more, overweight women with weight loss of 5-<15%, and women in all BMI categories with weight loss of 15% or more were at increased risk of death from all causes compared with those in the same BMI category who lost <5%; hazard ratios ranged from 1.46 to 2.70. Weight loss of 5-<15% reduced risk of death from cardiovascular diseases among obese men. CONCLUSIONS: Weight loss of 15% or more from maximum body weight is associated with increased risk of death from all causes among overweight men and among women regardless of maximum BMI.

The relationship between fish consumption and stroke incidence. The NHANES I Epidemiologic Follow-up Study (National Health and Nutrition Examination Survey).

OBJECTIVE: To assess the level of fish consumption as a risk factor fo r stroke. METHODS: Participants were members of the National Health and Nutrition Examination Survey I Epidemiologic Follow-up Study, a longitudinal cohort study of a national sample. Included in this analysis were white and black women and men aged 45 to 74 years when examined in 1971 through 1975 who did not report a history of stroke at that time. Average follow-up for survivors was 12 years (maximum, 16 years). The main outcome measure was incident stroke (fatal and nonfatal). Fish consumption at baseline was obtained from a 3-month food frequency questionnaire. RESULTS: White women aged 45 to 74 years who consumed fish more than once a week had an age-adjusted risk of stroke incidence only about half that of women who never consumed fish. This effect persisted after controlling for multiple stroke risk variables (relative risk, 0.55;95% confidence interval [CI], 0.32 to 0.93). Fish consumption more than once a week compared with never was not associated with age-adjusted stroke risk in white men aged 45 to 74 years (relative risk, 0.85;95%CI,0.49 to 1.46). In black women and men combined aged 45 to 74 years, any fish consumption compared with never was significantly associated with reduced adjusted stroke risk (relative risk, 0.51;95%CI,0.30 to 0.88).

Phalangeal bone density and hip fracture risk.

OBJECTIVE: To assess the long-term predictive usefulness of radiographic absorptiometry measurements of phalangeal bone density for hip fracture risk. METHODS: Participants were members of the First National Health and Nutrition Examination Survey Epidemiologic Follow Up Study cohort. Subjects were followed up for a maximum of 16 years. The First National Health and Nutrition Examination Survey data were obtained from a nationally representative sample of non-institutionalized civilians. A cohort of 3481 white and black subjects (1559 white women) aged 45 through 74 years at baseline (1971-1975) were observed through 1987. Ninety-eight percent of the original cohort completed the study. Hospital records and death certificates were used to identify a total of 72 hip fracture cases. Phalangeal bone density at baseline was measured using photodensitometry (PD), and later reanalyzed by radiographic absorptiometry (RA), a newer, more sophisticated technique. RESULTS: Results were evaluated to determine the relative risk for hip fracture per 1-SD decrease in bone density, after controlling for age at baseline, race, gender, weight, and previous fractures. Both RA and PD measurements showed a significant inverse relationship to hip fracture risk, with RA density measurements showing a slightly higher adjusted relative risk per 1-SD density decrease than PD measurements. For RA bone density, the relative risk for all subjects was 1.81 (95% confidence interval, 1.34-2.44) compared with 1.57 (95% confidence interval, 1.19-2.07) for PD bone density after adjusting for age at baseline, race, gender, weight, and previous fractures. Results for white women were essentially the same as those for all subjects for RA bone density and PD bone density. CONCLUSIONS: Phalangeal bone density determined from standard hand x-ray films is a significant predictor of future hip fracture risk. Availability of a valid method to assess fracture risk using conventional radiographs will expand the ability to identify individuals with osteoporosis.

Risk factors for hip fracture in white men: the NHANES I Epidemiologic Follow-up Study.

This prospective population-based study assessed predictors of hip fracture risk in white men. Participants were members of the Epidemiologic Follow-up Study cohort of the First National Health and Nutrition Examination Survey, a nationally representative sample of noninstitutionalized civilians who were followed for a maximum of 22 years. A cohort of 2879 white men (2249 in the nutrition and weight-loss subsample, 1437 in the bone density subsample) aged 45-74 years at baseline (1971-1975) were observed through 1992. Ninety-four percent of the original cohort were successfully traced. Hospital records and death certificates were used to identify a total of 71 hip fracture cases (61 in the nutrition and weight-loss subsample, 26 in the bone-density subsample). Among the factors evaluated were age at baseline, previous fractures other than hip, body mass index, smoking status, alcohol consumption, nonrecreational physical activity, weight loss from maximum, calcium intake, number of calories, protein consumption, chronic disease prevalence, and phalangeal bone density. The risk adjusted relative risk (RR) of hip fracture was significantly associated with presence of one or more chronic conditions (RR = 1.91, 95% confidence interval [CI] = 1.19-3.06), weight loss from maximum > or = 10% (RR = 2.27, 95% CI 1.13-4.59), and 1 SD change in phalangeal bone density (RR = 1.73, 95% CI 1.11-2.68). No other variables were significantly related to hip fracture risk. Although based on a small number of cases, this is one of the first prospective studies to relate weight loss and bone density to hip fracture risk in men.

Baseline serum total cholesterol and coronary heart disease incidence in African-American women (the NHANES I epidemiologic follow-up study). National Health and Nutrition Examination Survey.

Proportional-hazards analyses for African-American women aged 25 to 74 revealed a variable association of coronary heart disease risk with baseline serum total cholesterol (after adjusting for age fifth vs first quintile: RR = 1.62, 95% confidence interval [CI] 0.89 to 2.98, p = 0.12; after adjusting for age, systolic blood pressure, body mass index, smoking, history of diabetes, low education, and low family income: RR = 1.88, 95% CI 1.02 to 3.45, p = 0.04). Perhaps due to the relatively small number of events, the association of serum total cholesterol with coronary heart disease incidence in African-American women was not consistently significant.

White blood cell count and hypertension incidence. The NHANES I Epidemiologic Follow-up Study.

To test the hypothesis that elevated white blood cell count (WBC) is associated with increased incidence of essential hypertension, data from the NHANES I Epidemiologic Follow-up Study (NHEFS) were analyzed. Incidence of hypertension was determined in a cohort of 5782 white and 674 black persons with complete data who were normotensive at baseline. There was a statistically significant increase of about 50% in risk of hypertension over approximately 10 years' follow-up in white men aged 25-74 years with WBC > 8600 compared to men with WBC < 6200 cells/mm3. The association was independent of other risk variables. In white women, an association of high WBC with increased age-adjusted risk of hypertension was seen only at ages 45-64 and 65-74 years. The association was diminished and no longer significant after controlling for multiple risk variables. Data for black women suggested an increased risk among women with higher WBC compared to those with lower WBC at ages 65-74 after controlling other risk variables (p = 0.0001). No positive association was seen in black men. Thus, data from NHEFS confirm the previously reported association of higher WBC with increased incidence of hypertension in white men, and possibly older white and black women. Given the lack of a compelling biological explanation, further studies of this association are needed, especially in women and blacks.

Diabetes mellitus, coronary heart disease incidence, and death from all causes in African American and European American women: The NHANES I epidemiologic follow-up study.

Few data are available on risk for coronary heart disease in African American women with diabetes mellitus, a well-established coronary risk factor in European American women. This study tests the hypothesis that medical history of diabetes predicts coronary heart disease incidence in African American women in a national cohort. Participants in the NHANES I Epidemiologic Follow-up Study in this analysis were 1035 African American and 5732 European American women aged 25-74 years without a history of coronary heart disease. Average follow-up for survivors was 19 years (maximum 22 years). Risk of incident coronary heart disease by baseline diabetes status was estimated. Proportional hazards analyses for African American women aged 25-74 revealed significant associations of coronary heart disease risk with diabetes after adjusting for age (RR = 2.40; 95% CI, 1.58-3.64, P < 0.01). After adjusting for age, smoking, and low education, there was an elevated risk in diabetics age 25-74 (RR = 2. 34; 95% CI, 1.54-3.56, P < 0.01); this association did not differ significantly from that for European American women. Excess coronary incidence in African American compared to European American women aged 25-64 was statistically explained by controlling for diabetes history, age, education, and smoking but only partly explained by age and diabetes history. In African American women aged 25-74, diabetes was also associated with increased coronary heart disease, cardiovascular, and all-cause mortality. The population attributable risk of coronary heart disease incidence associated with a medical history of diabetes was 8.7% in African American women and 6.1% in European American women. Medical history of diabetes was a significant predictor of coronary heart disease incidence and mortality in African American women and explained some of the excess coronary incidence in younger African American compared to European American women.

Erythrocyte sedimentation rate and coronary heart disease: the NHANES I Epidemiologic Follow-up Study.

Erythrocyte sedimentation rate (ESR) is a simple and relatively inexpensive laboratory test. Data were examined to determine whether elevated ESR was a predictor of CHD incidence and death in a large U.S. national sample of persons aged 45-74 at baseline. In the NHANES I Epidemiologic Follow-up Study cohort, white men aged 45-64 years with ESR in the upper quintile at baseline had increased incidence of CHD (RR = 1.73, 95% CL 1.12, 2.68) over a 15 year follow-up after controlling multiple risk factors compared to white men with ESR in the lowest quintile. Furthermore, men aged 45-64 with ESR in the upper quintile had more than twice the risk of CHD death (RR = 2.73, 95% CL 1.21, 6.15) of men with ESR in the lowest quintile after adjusting other risk factors. No significant associations were seen in white women. The mechanism of this association is unclear. Further studies are needed to replicate this finding and elucidate the mechanism for this association in longitudinal studies in which plasma fibrinogen, HDL cholesterol, as well as ESR are measured.

Fish consumption and hypertension incidence in African Americans and whites: the NHANES I Epidemiologic Follow-up Study.

We sought to test the hypothesis that increased consumption of fish is associated with decreased incidence of essential hypertension. Data on fish consumption and incidence of hypertension from a national cohort of 5,394 blacks and whites normotensive at baseline and followed 10 years in the NHANES I Epidemiologic Follow-up Study (NHEFS) were analyzed. Our results showed that whites aged 25-74 years had no significant association of fish consumption with incidence of hypertension. In black women, after adjusting for multiple risk factors, those who increased their fish intake from <1 time/week to > or = 1 time/week had RR = 0.42, 95% CI 0.22-0.81, p = 0.009. However, those with high intake both times had adjusted RR = 0.75, 95% CI 0.45-1.26, p = 0.28. No consistent significant associations of fish consumption with hypertension incidence were found, perhaps because fish consumption in this population was low. Further studies are needed in blacks.

Symptoms of depression as a prospective risk factor for stroke.

OBJECTIVE: The objective of this study was to assess baseline levels of depression as a risk factor for stroke among white and black men and women. METHODS: A population-based cohort of 6095 stroke-free white and black men and women aged 25 to 74 years in the NHANES I Epidemiologic Followup Study were followed for an average of 16 years to a maximum of 22 years. The association between stroke and baseline self-reported depressive symptomatology was analyzed using Cox proportional hazards models adjusting for baseline age, race, sex, education, smoking status, body mass index, alcohol use, nonrecreational physical activity, serum cholesterol level, history of diabetes, history of heart disease, and systolic blood pressure. Hospital records and death certificates were used to identify stroke cases; a total of 483 cases were identified. RESULTS: In age-adjusted models for all persons, white men, white women, and black persons of both sexes, depression was predictive of stroke. In risk-adjusted models for all persons (relative risk (RR) = 1.73, 95% confidence interval (CI) = 1.30-2.31) and for white men (RR = 1.68, 95% CI = 1.02-2.75), depression remained predictive of stroke. For white women, depression (RR = 1.52, 95% CI = 0.97-2.38) reached borderline significance (p = .07). For black persons, depression (RR = 2.60, 95% CI = 1.40-4.80) demonstrated a higher risk of stroke. A series of supplemental analyses also supported the association between depression and stroke. CONCLUSIONS: Depression is predictive of stroke across all strata. This nationally representative study gives evidence of a prospective association between depression and stroke.

Physical activity and stroke incidence in women and men. The NHANES I Epidemiologic Follow-up Study.

To test the hypothesis that physical inactivity is associated with increased stroke risk in women and men, the authors analyzed data from a longitudinal cohort study with three follow-up data collection waves. In the Nation Health and Nutrition Examination Survey I (NHANES I) Epidemiologic Follow-up Study, 7,895 white persons and black persons aged 45-74 years were examined in 1971-1975 as part of NHANES I. Included in this analysis were 5,852 persons without a history of stroke (fatal and nonfatal) or missing data. The average follow-up was 11.6 years (maximum, 16.4 years). Incident stroke (fatal or nonfatal) was the main outcome measure. Events were ascertained from cause of death information coded from death certificates and from discharge diagnoses coded from hospital and nursing home records during the follow-up period (1971 through 1987). Participants were asked to characterize their level of habitual physical activity as low, moderate, of high. The relative risk for stroke was estimated by Cox proportional hazards regression analysis, comparing persons reporting low with those reporting high physical activity at baseline and persons in the upper with those in the lower tertile of resting pulse rate. There were 249 incident cases of stroke identified in white women, 270 in white men, and 104 in blacks. In white women aged 65-74 years, low nonrecreational activity was associated with an increased risk of stroke (relative risk = 1.82,95% confidence interval 1.10-3.02) after adjusting for the baseline risk factors of age, smoking, history of diabetes, history of heart disease, education, systolic blood pressure, serum total cholesterol, body mass index, and hemoglobin concentration. Similar associations were seen for men and for blacks and for low recreational activity in women. A higher resting pulse rate was associated with an increased risk of stroke in blacks but not in whites. A consistent association of reported low physical activity with an increased risk of stroke was observed in white women. Regular physical activity may be of benefit in preventing stroke in women as well as men.

Jogging and bone mineral density in men: results from NHANES III.

OBJECTIVES: This cross-sectional population-based study assessed the association of jogging with femoral bone mineral density (BMD) in men. METHODS: Data are from a nationally representative sample of 4254 men aged 20 to 59 years from the Third National Health and Nutrition Examination Survey (NHANES III). Total femoral BMD was measured by dual energy x-ray absorptiometry. Jogging was self-reported. RESULTS: Jogging (any vs none) was strongly associated with higher BMD in multivariate models (P < .01) for both young and middle-aged men. Men who jogged 9 or more times per month had higher BMD levels than those who jogged only 1 to 8 times per month (P = .01). CONCLUSIONS: Jogging is associated with higher femoral neck BMD in men. Additional large-scale studies that measure all aspects of jogging are warranted.

Body fat distribution, obesity, overweight and stroke incidence in women and men--the NHANES I Epidemiologic Follow-up Study.

OBJECTIVE: To test the hypothesis that an elevated ratio of subscapular to triceps skinfold thickness (SFR), a measure of truncal obesity, is associated with increased incidence of stroke independent of overweight. DESIGN: Data from the NHANES I Epidemiologic Follow-up Study were analyzed. SUBJECTS: A cohort of 3652 women and 3284 men with complete data who had no history of stroke at baseline in 1971-1975. MEASUREMENTS: Incidence of stroke diagnosed at hospital discharge or death during the follow-up period through 1992; triceps and subscapular skinfold thickness (SSF) and body mass index (BMI) at baseline. RESULTS: In a complex relationship, higher SFR was associated with a mildly but significantly increased incidence of stroke only in white male former smokers. In white men, SSF showed a U-shaped association with stroke risk. In white men, stroke risk was elevated in the top quartile of BMI only in never smokers. In black women, stroke risk was significantly elevated in the bottom compared to the top quartile of BMI. No significant associations were seen in white women or black men. CONCLUSIONS: In white men, SSF showed a U-shaped association with stroke risk, which was elevated in the top quartile of BMI only in never smokers. Surprisingly, stroke risk was elevated in black women with the lowest BMI. More studies of these associations are needed, especially in black women.

Body fat distribution and hypertension incidence in women and men. The NHANES I Epidemiologic Follow-up Study.

OBJECTIVE: To test the hypothesis that an elevated ratio of subscapular to triceps skinfold thickness (SFR), one measure of truncal obesity, is associated with increased incidence of essential hypertension. DESIGN: Data from the NHANES I Epidemiologic Follow-up Study (NHEFS) were analyzed. SUBJECTS: A cohort of 4303 women and 2579 men with complete data who were normotensive at baseline in 1971-1975. MEASUREMENTS: Incidence of hypertension, blood pressure 160/95 mm Hg or greater or on blood pressure medication at follow-up in 1982-1984. RESULTS: There was a statistically significant increase in risk of hypertension over approximately 10 y follow-up in white women aged 25-74 y with SFR in the fifth compared to the first quintile independent of age and body mass index (BMI) (relative risk = 1.52, 95% confidence interval 1.13-2.06, P = 0.006). The association was somewhat diminished after controlling for baseline blood pressure, change in BMI and other risk variables. An even stronger association was seen for subscapular skinfold and hypertension incidence. In white men aged 25-74 y, a significant association of high SFR with age-, BMI-adjusted risk of hypertension was seen (RR = 1.41, 95% CI 1.01-1.96, P = 0.04). Data for black women or black men failed to reveal significant variation in hypertension risk among quintiles of SFR or subscapular skinfold except in black women with low baseline BMI. CONCLUSIONS: Data from NHEFS confirm the association of higher truncal obesity with increased incidence of hypertension in white women. Further studies are needed, especially in larger samples of black women.

Coronary heart disease risk factors and attributable risks in African-American women and men: NHANES I epidemiologic follow-up study.

OBJECTIVES: This study assessed associations of risk factors with coronary heart disease incidence in African Americans. METHODS: The participants in the NHANES I Epidemiologic Follow-Up Study included in this analysis were 1641 Black and 9660 White persons who were aged 25 to 74 years when examined and who did not have a history of coronary heart disease. Average follow-up for survivors was 19 years. RESULTS: Significant, independent risk factors for coronary heart disease were age, systolic blood pressure, and smoking in Black women and age, systolic blood pressure, serum cholesterol, low education, and low family income in Black men. In this cohort, 19% of incident coronary heart disease in Black women and 34% in Black men might be prevented if systolic blood pressure were below 140 mm Hg. In Black men, attributable risk for low education (46%) was even higher than that for elevated blood pressure. CONCLUSIONS: Elevated systolic blood pressure and smoking were predictive of coronary heart disease incidence in African Americans. Estimates of population attributable risk were highest for elevated systolic blood pressure in women and education less than high school in men. Further studies of serum lipids, education, and coronary heart disease in Black women are needed.

Coronary heart disease incidence and survival in African-American women and men. The NHANES I Epidemiologic Follow-up Study.

BACKGROUND: Relatively few data are available on risk for or survival with coronary heart disease in African-American persons. OBJECTIVE: To determine whether incidence of coronary heart disease, rate of survival with the disease, and rate of coronary surgery differ between ethnic groups. DESIGN: Prospective cohort study. SETTING: United States. PARTICIPANTS: Persons who responded to the National Health and Nutrition Examination Survey (NHANES) I Epidemiologic Follow-up Study. Included in this analysis were 11406 white persons and African-American persons aged 25 to 74 years who had no history of coronary heart disease. Average follow-up for survivors was 19 years (maximum, 22 years). MEASUREMENTS: Incident coronary heart disease. RESULTS: Compared with that in white persons, the age-adjusted risk for coronary heart disease was higher in African-American women aged 25 to 54 years (relative risk, 1.76 [95% CI, 1.36 to 2.29]) but was lower in African-American men within each age subgroup. The age-adjusted risk was lower in African-American men for all ages combined (25 to 74 years) (relative risk, 0.78 [CI, 0.65 to 0.93] for coronary heart disease and 0.62 [CI, 0.42 to 0.92] for acute myocardial infarction). The higher rate in African-American women aged 25 to 54 years could be explained statistically by the higher risk factor levels in these women. Ethnic groups did not significantly differ in survival after the first hospitalization for coronary heart disease. However, the incidence of coronary procedures after hospitalization for coronary heart disease was markedly lower in African-American persons than in white persons (age- and sex-adjusted relative risk, 0.40 [CI, 0.16 to 0.99]). CONCLUSIONS: Total incidence of coronary heart disease is higher in African-American women aged 25 to 54 years than in white women of the same ages and is lower in African-American men aged 25 to 74 years than in white men of the same ages.

Weight loss from maximum body weight among middle-aged and older white women and the risk of hip fracture: the NHANES I epidemiologic follow-up study.

Although weight loss increases bone loss and hip fracture risk in older women, little is known about the relation between weight loss in middle-aged women and subsequent hip fracture risk. The objective of this study was to determine the association between weight loss from reported maximum body weight in middle-aged and older women and the risk of hip fracture. Data were from a nationally representative sample of 2180 community-dwelling white women aged 50-74 years from the Epidemiologic Follow-up Study of the first National Health and Nutrition Examination Survey (NHEFS). In this prospective cohort study, incident hip fracture was ascertained during 22 years of follow-up. The adjusted relative risks associated with weight loss of 10% or more from maximum body weight were elevated for both middle-aged (RR 2.54; 95% CI 1.10-5.86) and older women (RR 2.04; 95% CI 1.37-3.04). For both ages combined, women in the lowest tertile of body mass index at maximum who lost 10% or more of weight had the highest risk of hip fracture (RR 2.37; 95% CI 1.32-4.27). Weight loss from maximum reported body weight in women aged 50-64 years and 65-74 years increased their risk of hip fracture, especially among those who were relatively thin. Weight loss of 10% or more from maximum weight among both middle-aged and older women is an important indicator of hip fracture risk.

Plan and operation of the NHANES I Epidemiologic Followup Study, 1992.

OBJECTIVES: The NHANES I Epidemiologic Followup Study (NHEFS) is a longitudinal study that uses as its baseline those adult persons 25-74 years of age who were examined in the first National Health and Nutrition Examination Survey (NHANES I). NHEFS was designed to investigate the association between factors measured at baseline and the development of specific health conditions. The three major objectives of NHEFS are to study morbidity and mortality associated with suspected risk factors, changes over time in participants' characteristics, and the natural history of chronic disease and functional impairments. METHODS: Tracing and data collection in the 1992 Followup were undertaken for the 11,195 subjects who were not known to be deceased in the previous surveys. No additional information was collected in the 1992 NHEFS for the 3,212 subjects who were known to be deceased before the 1992 NHEFS data collection period. RESULTS: By the end of the 1992 NHEFS survey period, 90.0 percent of the 11,195 subjects in the 1992 Followup cohort had been successfully traced. Interviews were conducted for 9,281 subjects. An interview was conducted for 8,151 of the 8,687 surviving subjects; 551 interviews were administered to a proxy respondent because the subject was incapacitated. A proxy interview was conducted for 1,130 of the 1,392 decedents identified in the 1992 NHEFS. In addition, 10,535 facility stay records were collected for 4,162 subjects reporting overnight facility stays. Death certificates were obtained for 1,374 of the 1,392 subjects who were identified as deceased since last contact. Approximately 32 percent of the NHEFS cohort is known to be deceased with a death certificate available for 98 percent of the 4,604 NHEFS decedents.