The epidemiology of recent involuntary weight loss in the United States population.

BACKGROUND: Although recent involuntary weight loss (RIWL) has been associated with mortality, no national studies described the prevalence among the general population, characteristics and long-term outcomes of people with RIWL. METHODS: The authors analyzed data from the NHANES II Mortality Study of 5838 individuals 50-74.9 years old who between 1976-1980 underwent a physical examination that included height and weight measurements, biochemical tests and responded to questions about involuntary weight loss within the past six months. Vital status was determined through 1992. Logistic regression was used to examine characteristics associated with RIWL and Cox proportional hazard modeling was used to measure associations between RIWL and mortality. RESULTS: 13.3% of the population reported RIWL with 6.9% reporting > or = 5% RIWL. Obese individuals were at significantly higher risk of RIWL of > or = 5% compared to those with BMI 19-24.9 (OR=1.57. 95% CI: 1.13, 2.18). Other significant risk factors for RIWL included; poor self-reported health, cancer, high white blood cell count, low albumin and low hemoglobin levels, age and current smoking status. RIWL of > or = 5% was significantly associated with mortality (RR=1.24, 95% CI: 1.01, 1.53). CONCLUSION: In summary, RIWL is fairly common among community-dwelling older adults, occurs disproportionately among obese individuals, is associated with characteristics of poor health and independently associated with mortality. These results indicate that RIWL needs to be considered an adverse health indicator even among obese individuals and despite the absence of several clinical indicators of disease.

The politics of preventable deaths: local spending, income inequality, and premature mortality in US cities.

OBJECTIVE: To examine the association between (1) local political party, (2) urban policies, measured by spending on local programmes, and (3) income inequality with premature mortality in large US cities. DESIGN: Cross sectional ecological study. OUTCOME MEASURES: All cause death rates and death rates attributable to preventable or immediate causes for people under age 75. PREDICTOR MEASURES: Income inequality, city spending, and social factors. SETTING: All central cities in the US with population equal to or greater than 100 000. RESULTS: Income inequality is the most significant social variable associated with preventable or immediate death rates, and the relation is very strong: a unit increase in the Gini coefficient is associated with 37% higher death rates. Spending on police is associated with 23% higher preventable death rates compared with 14% lower death rates in cities with high spending on roads. CONCLUSIONS: Cities with high income inequality and poverty are so far unable to reduce their mortality through local expenditures on public goods, regardless of the mayoral party. Longitudinal data are necessary to determine if city spending on social programmes reduces mortality over time.

Summary measures of population health: addressing the first goal of healthy people 2010, improving health expectancy.

This report is one of several Healthy People Statistical Notes that evaluate methodological issues pertaining to summary measures - statistics that combine mortality and morbidity data to represent overall population health in a single number. This report evaluates the consequences of changes in the components of health expectancy measures (i.e., mortality or morbidity) on the overall measure. Any activity limitation is used as a morbidity measure. Simulations are used to evaluate the impacts of reducing 1995 age-specific mortality or activity limitation rates by 5, 10, 25, and 50 percent at all ages. Then it is limited to ages under 25 years, 25 -64 years, and over 64 years. The impact of completely eliminating mortality or activity limitation for the younger age groups is also examined. In general, reducing morbidity rates results in greater changes than the same percent reduction in death rates. The same proportional reduction in age-specific rates for either mortality or morbidity has a greater impact if it occurs at older ages. Reducing mortality results in a greater change in life expectancy than in health expectancy and a decline in the proportion of life lived in healthy states. Reducing morbidity increases both health expectancy and the proportion of life lived in healthy states. Simultaneous reductions in mortality and morbidity have additive effects on health expectancy.

State-level income inequality and individual mortality Risk: A prospective, multilevel study

Multilevel models do allow us to examine the question of which subpopulations show an effect of income inequality on health. Many hypotheses are possible. For example, one could argue that we should only expect those who are most marginalized and vulnerable to suffer. Alternatively, one could argue that the cost of deep economic divides is spread across the population through increased levels of crime and decreased commitment to the "commons." Although it is still too early to come to a definitive conclusion, the general pattern of results is not consistent with the latter scenario. (Sign-in is necessary for full-text)

State-level income inequality and individual mortality risk: a prospective, multilevel study.

OBJECTIVES: Previous studies have linked state-level income inequality to mortality rates. However, it has been questioned whether the relationship is independent of individual-level income. The present study tests whether state-level income inequality is related to individual mortality risk, after adjustment for individual-level characteristics. METHODS: In this prospective, multilevel study design, the vital status of National Health Interview Survey (NHIS) respondents was ascertained by linkage to the National Death Index, with additional linkage of state-level data to individuals in the NHIS. The analysis included data for 546,888 persons, with 19,379 deaths over the 8-year follow-up period. The Gini coefficient was used as the measure of income inequality. RESULTS: Individuals living in high-income-inequality states were at increased risk of mortality (relative risk = 1.12; 95% confidence interval = 1.04, 1.19) compared with individuals living in low-income-inequality states. In stratified analyses, significant effects of state income inequality on mortality risk were found, primarily for near-poor Whites. CONCLUSIONS: State-level income inequality appears to exert a contextual effect on mortality risk, after income is adjusted for, providing further evidence that the distribution of income is important for health.

Intentional weight loss and mortality among overweight individuals with diabetes.

OBJECTIVE: To estimate the effect of intentional weight loss on mortality in overweight individuals with diabetes. RESEARCH DESIGN AND METHODS: We performed a prospective analysis with a 12-year mortality follow-up (1959-1972) of 4,970 overweight individuals with diabetes, 40-64 years of age, who were enrolled in the American Cancer Society's Cancer Prevention Study I. Rate ratios (RRs) were calculated, comparing overall death rates, and death from cardiovascular disease (CVD) or diabetes in individuals with and without reported intentional weight loss. RESULTS: Intentional weight loss was reported by 34% of the cohort. After adjustment for initial BMI, sociodemographic factors, health status, and physical activity, intentional weight loss was associated with a 25% reduction in total mortality (RR = 0.75; 95% CI 0.67-0.84), and a 28% reduction in CVD and diabetes mortality (RR = 0.72; 0.63-0.82). Intentional weight loss of 20-29 lb was associated with the largest reductions in mortality (approximately 33%). Weight loss >70 lb was associated with small increases in mortality CONCLUSIONS: Intentional weight loss was associated with substantial reductions in mortality in this observational study of overweight individuals with diabetes.

The widening gap in death rates among income groups in the United States from 1967 to 1986.

Death rates in the United States have fallen since the 1960s, but improvements have not been shared equally by all groups. This study investigates the change in inequality in mortality by income level from 1967 to 1986. Comparable death rates are constructed for 1967 and 1986 using National Mortality Followback Surveys as numerators and National Health Interview Surveys as denominators. Direct age-adjusted death rates are calculated for income levels for the U.S. noninstitutionalized civilian population 35 to 64 years old. A summary measure of inequality in mortality adjusts for differences in the size and definition of income groups in the two years. In both 1967 and 1986, mortality decreased with each rise in income level. Measured in relative terms, this inverse relationship was greater in 1986 then in 1967 for men and women, blacks and whites. Between 1967 and 1986, death rates for those with maximal income declined between two and three times more rapidly than did rates for the middle and low income groups. The greatest increase in relative inequality was seen among white males.

Estrogen replacement therapy and incidence of self-reported physician-diagnosed arthritis.

BACKGROUND: This longitudinal study examined the association between use of estrogen replacement therapy and incidence of self-reported, physician-diagnosed arthritis. METHODS: Data of 2,416 postmenopausal women who participated in the National Health and Nutrition Examination Survey Epidemiological Follow-Up Study were used in this study. Women, free of self-reported arthritis at entry into study and for 3 years thereafter, were questioned about use of estrogen and physician-diagnosed arthritis at each of the follow-up waves of study. Proportional hazard regression models were used for the analysis. RESULTS: Use of ERT was found to be associated with higher risk of incident arthritis, after adjusting for potential confounders (RR = 1.61, CI 1.37-1.89). Whenever use of ERT was replaced by duration of use in the regression model, ERT users for a year or less significantly increased their risk of incident arthritis (RR = 1.37, CI 1.07-1.74). The risk increased by 30 and 96% with hormone use for 1 to 4 and 4 to 10 years, respectively, and by 104% with hormone use for 10 or more years. CONCLUSION: Results suggest that users of ERT were at higher risk of developing arthritis and the longer the use of the hormone, the higher the risk.

Prospective study of intentional weight loss and mortality in overweight white men aged 40-64 years.

Although 25% of US men indicate that they are trying to lose weight, the association between intentional weight loss and longevity in men is unknown. The authors analyzed prospective data from 49,337 overweight (initial body mass index > or =27) white men aged 40-64 years who, in 1959-1960, answered questions on weight change direction, amount, time interval, and intent. Vital status was determined in 1972. Proportional hazards regression estimated mortality rate ratios for men who intentionally lost weight compared with men with no weight change. Analyses were stratified by health status and adjusted for age, initial body mass index, smoking status, alcohol intake, education, physical activity, health history, and physical symptoms. Among men with no reported health conditions (n = 36,280), intentional weight loss was not associated with total, cardiovascular (CVD), or cancer mortality, but diabetes-associated mortality was increased 48% (95% confidence interval (CI) -7% to +133%) among those who lost 20 pounds (9.1 kg) or more; this increase was largely related to non-CVD mortality. Among men with reported health conditions (n = 13,057), intentional weight loss had no association with total or CVD mortality, but cancer mortality increased 25% (95% confidence interval -4% to +63%) among those who lost 20 pounds or more. Diabetes-associated mortality was reduced 32% (95% confidence interval -52% to -5%) among those who lost less than 20 pounds and 36% (95% confidence interval -49% to -20%) among those who lost more than 20 pounds. These results and those from our earlier study in women (Williamson et al., Am J Epidemiol 1995;141:1128-41) suggest that intentional weight loss may reduce the risk of dying from diabetes, but not from CVD. In observational studies, however, it is difficult to separate intentional weight loss from unintentional weight loss due to undiagnosed, underlying disease. Well-designed observational studies, as well as randomized controlled trials, are needed to determine whether intentional weight loss reduces CVD mortality.

PIP: The association between intentional weight loss and mortality is examined using data on 49,337 overweight white men aged 40-64 from the American Cancer Society's Cancer Prevention Study I. These data were originally collected in 1959-1960, and vital status reassessed in 1972. The results, along with an earlier study on women, suggest that intentional weight loss may reduce the risk of dying from diabetes, but not from cardiovascular effects. The difficulty of distinguishing between intentional and unintentional weight loss in such studies is stressed. Comments on the paper by Lewis H. Kuller are included (pp. 515-6) as well as a response from the principal author (pp. 517-8).

Body mass index, weight change, and incidence of self-reported physician-diagnosed arthritis among women.

OBJECTIVES: This study examined the relationship between body mass index (BMI), weight change, and arthritis in women. METHODS: Data were taken from the 1982-1984 National Health and Nutrition Examination Survey Epidemiologic Follow-Up Study of 3617 women, aged 25 to 74 years. RESULTS: Women with a BMI greater than 32 at initial interview were at significantly higher risk of developing arthritis than women with a BMI of 19 to 21.9. Compared with stable-weight women with a BMI of less than 25, women who were obese at initial interview (BMI > 29) and who subsequently maintained their weight or gained more than 10% of their body weight were at significantly higher risk of developing arthritis. CONCLUSIONS: Attaining and maintaining a healthy weight may reduce the risk of developing arthritis.

Income inequality and mortality in metropolitan areas of the United States.

OBJECTIVES: This study examined associations between income inequality and mortality in 282 US metropolitan areas. METHODS: Income inequality measures were calculated from the 1990 US Census. Mortality was calculated from National Center for Health Statistics data and modeled with weighted linear regressions of the log age-adjusted rate. RESULTS: Excess mortality between metropolitan areas with high and low income inequality ranged from 64.7 to 95.8 deaths per 100,000 depending on the inequality measure. In age-specific analyses, income inequality was most evident for infant mortality and for mortality between ages 15 and 64. CONCLUSIONS: Higher income inequality is associated with increased mortality at all per capita income levels. Areas with high income inequality and low average income had excess mortality of 139.8 deaths per 100,000 compared with areas with low inequality and high income. The magnitude of this mortality difference is comparable to the combined loss of life from lung cancer, diabetes, motor vehicle crashes, human immunodeficiency virus (HIV) infection, suicide, and homicide in 1995. Given the mortality burden associated with income inequality, public and private sector initiatives to reduce economic inequalities should be a high priority.

Are geographic regions with high income inequality associated with risk of abdominal weight gain?

Geographic regions characterized by income inequality are associated with adverse mortality statistics, but the pathophysiologic mechanisms that mediate this ecologic relationship have not been elucidated. This study used a United States mail survey of 34158 male and 42741 female healthy-adult volunteers to test the association between residence in geographic regions with relative income inequality and the likelihood of weight gain at the waist. Respondents came from 21 states that were characterized by the household income inequality (HII) index, a measure reflecting the proportion of total income received by the more well off 50% of households in the state. The main outcome measure was self-reported weight gain mainly at the waist as opposed to weight gain at other anatomic sites. After controlling for age, other individual-level factors, and each state's median household income, men's likelihood of weight gain at the waist was positively associated (p = 0.0008) with the HII index. Men from states with a high HII (households above the median receive 81.6% to 82.6% of the income) described weight gain at the waist more often than men from states with a low HII (households above the median receive 77.0% to 78.5% of the income) (odds ratio = 1.12, 95% confidence interval 1.03 to 1.22). Women's results showed a non-significant trend in the same direction. An association between ecologically defined socio-environmental stress and abdominal obesity may help to clarify the pathophysiologic pathways leading to several major chronic diseases.

The effect of age on the association between body-mass index and mortality.

BACKGROUND: The effect of age on optimal body weight is controversial, and few studies have had adequate numbers of subjects to analyze mortality as a function of body-mass index across age groups. METHODS: We studied mortality over 12 years among white men and women who participated in the American Cancer Society's Cancer Prevention Study I (from 1960 through 1972). The 62,116 men and 262,019 women included in this analysis had never smoked cigarettes, had no history of heart disease, stroke, or cancer (other than skin cancer) at base line in 1959-1960, and had no history of recent unintentional weight loss. The date and cause of death for subjects who died were determined from death certificates. The associations between body-mass index (defined as the weight in kilograms divided by the square of the height in meters) and mortality were examined for six age groups in analyses in which we adjusted for age, educational level, physical activity, and alcohol consumption. RESULTS: Greater body-mass index was associated with higher mortality from all causes and from cardiovascular disease in men and women up to 75 years of age. However, the relative risk associated with greater body-mass index declined with age. For example, for mortality from cardiovascular disease, the relative risk associated with an increment of 1 in the body-mass index was 1.10 (95 percent confidence interval, 1.04 to 1.16) for 30-to-44-year-old men and 1.03 (95 percent confidence interval, 1.02 to 1.05) for 65-to-74-year-old men. For women, the corresponding relative risk estimates were 1.08 (95 percent confidence interval, 1.05 to 1.11) and 1.02 (95 percent confidence interval, 1.02 to 1.03). CONCLUSIONS: Excess body weight increases the risk of death from any cause and from cardiovascular disease in adults between 30 and 74 years of age. The relative risk associated with greater body weight is higher among younger subjects.

Validity of self-reported hypertension in the National Health and Nutrition Examination Survey III, 1988-1991.

BACKGROUND: The National Health and Nutrition Examination Survey (NHANES) is the main data source for hypertension surveillance. However, because of a gap of almost 10 years between each NHANES, self-reported data from annual surveys need to be examined as an alternative data source. This study analyzes the validity of self-reported hypertension in a national sample of non-Hispanic whites, non-Hispanic blacks, and Mexican-Americans. METHODS: Sensitivity, specificity, and predictive values positive (PVP) and negative (PVN) of self-reported hypertension were calculated against two definitions of hypertension: the definition recommended by the Third Joint National Committee on Hypertension, JNC III (blood pressure > or = 140/90 and/or taking antihypertension medication) and a broader definition including control with lifestyle modifications. Data used come from the NHANES III, 1988-1991. RESULTS: Overall test characteristics using the JNC III definition are sensitivity 71%, specificity 90%, PVP 72%, and PVN 89%. Test characteristics were consistently higher for the broad than for the JNC III definition. Validity of self-reported hypertension is higher among women than among men and among persons with a medical visit during the past year than among those with no visits: validity was lowest among Mexican-American men. Due to the similarity between sensitivity and PVP, the prevalence of self-reported hypertension is nearly equal to the prevalence of JNC III-defined hypertension. CONCLUSIONS: Self-reported hypertension may be used for surveillance of hypertension trends, in the absence of measured blood pressure, among non-Hispanic whites and non-Hispanic black women and persons with a medical visit in the past year. Validation should be repeated with each NHANES.

Explaining the relation between education and postmenopausal breast cancer.

The authors examined the relation between socioeconomic status, as defined by education level, and postmenopausal breast cancer incidence using data from the National Health and Nutrition Examination Survey I Epidemiologic Followup Study. Female participants in the study were followed from 1971-1974 to 1992-1993. Cox proportional hazards modeling was used to determine the relation between breast cancer incidence and education level. There was a direct dose-response association between education level and postmenopausal breast cancer risk. Several breast cancer risk factors, including height and reproductive-related risks such as nulliparity, were found to mediate this relation. Adjustment for these factors reduced, but did not eliminate, the positive relation between education level and risk of postmenopausal breast cancer; however, the association was no longer statistically significant. The association between higher education and increased risk of breast cancer appears to be largely explained by differences in the known risk factors for breast cancer.

Trends in overweight among US adults from 1987 to 1993: a multistate telephone survey.

OBJECTIVES: Using data from the Behavioral Risk Factor Surveillance System, this study describes trends in the prevalence of overweight between 1987 and 1993. METHODS: Data were examined from 33 states participating in an ongoing telephone survey of health behaviors of adults (n = 387,704). Self-reported weights and heights were used to calculate sex-specific prevalence estimates of overweight for each year from 1987 to 1993. Time trends were evaluated with the use of linear regression. RESULTS: Between 1987 and 1993, the age-adjusted prevalence of overweight increased by 0.9% per year for both sexes (from 21.9% to 26.7% among men and from 20.6% to 25.4% among women). The increasing linear trend was observed in all subgroups of the population but was most notable for Black men (1.5% per year) and men living in the Northeast (1.4% per year). Secular changes in smoking and leisure-time physical activity did not entirely account for the increase in overweight. CONCLUSIONS: The prevalence of overweight among American adults increased by 5% between 1987 and 1993. Efforts are needed to explore the causes of this adverse trend and to find effective strategies to prevent obesity.

The 25-year health care costs of women who remain overweight after 40 years of age.

BACKGROUND AND PURPOSE: Previously published reports strongly suggest that being overweight is a risk factor for coronary heart disease, hypertension, diabetes, gallstones, and osteoarthritis in women. Substantial health care and medication costs are associated with these chronic health conditions. We used an incidence-based analysis to estimate the excess costs associated with women maintaining an overweight status during the 25-year period from age 40 to 65 years. METHODS: The health care costs of three hypothetical cohorts of 10,000 40-year-old women were extrapolated to age 65. The non-overweight cohort maintained a body mass index (BMI; weight [kg]/height [m2]) of 21 to 24.9; the moderately overweight cohort maintained a BMI of 25 to 28.9; the severely overweight cohort maintained a BMI of > or = 29. The number of fatal and nonfatal health outcomes in each cohort for heart disease, hypertension, diabetes mellitus, gallstones, and osteoarthritis was calculated with their associated costs. RESULTS: We estimated that when compared with the non-overweight cohort of 10,000 women, the cohort of 10,000 women who had a BMI of > or = 29 incurred excess costs of $53 million over a 25 year period (discounted at 3% per year) and 497 excess deaths. The cohort of 10,000 women who had a BMI of 25-28.9 incurred excess costs of $22 million (discounted at 3% per year) and 212 excess deaths, compared with the non-overweight cohort. CONCLUSIONS: The results of this study indicate that an estimated $16 billion will be spent during the next 25 years treating health outcomes associated with overweight in middle-aged women in the United States. Thus, a substantial health burden is associated with the increasing prevalence of overweight women in the United States. Preventing excess coronary heart disease, gall-stones, osteoarthritis, hypertension, and diabetes through prevention of weight gain, particularly among reproductive-aged women, may be a cost-effective strategy.

Inequality in income and mortality in the United States: analysis of mortality and potential pathways.

OBJECTIVE: To examine the relation between health outcomes and the equality with which income is distributed in the United States. DESIGN: The degree of income inequality, defined as the percentage of total household income received by the less well off 50% of households, and changes in income inequality were calculated for the 50 states in 1980 and 1990. These measures were then examined in relation to all cause mortality adjusted for age for each state, age specific deaths, changes in mortalities, and other health outcomes and potential pathways for 1980, 1990, and 1989-91. MAIN OUTCOME MEASURE: Age adjusted mortality from all causes. RESULTS: There was a significant correlation (r = -0.62 [corrected], P < 0.001) between the percentage of total household income received by the less well off 50% in each state and all cause mortality, unaffected by adjustment for state median incomes. Income inequality was also significantly associated with age specific mortalities and rates of low birth weight, homicide, violent crime, work disability, expenditures on medical care and police protection, smoking, and sedentary activity. Rates of unemployment, imprisonment, recipients of income assistance and food stamps, lack of medical insurance, and educational outcomes were also worse as income inequality increased. Income inequality was also associated with mortality trends, and there was a suggestion of an impact of inequality trends on mortality trends. CONCLUSION: Variations between states in the inequality of the distribution of income are significantly associated with variations between states in a large number of health outcomes and social indicators and with mortality trends. These differences parallel relative investments in human and social capital. Economic policies that influence income and wealth inequality may have an important impact on the health of countries.

Associations between measures of socioeconomic status and maternal health behavior.

Lower socioeconomic status (SES) is consistently associated with adverse pregnancy outcomes. One mechanism that may account for this association is that maternal health behaviors vary with SES. To examine this possibility, we addressed how women may be differently categorized by diverse measures of SES and the effect that choice of measure has on the relationship between SES and maternal health behaviors. We used population-based data for Caucasian women (n = 10,055) from Alaska, Maine, Oklahoma, and West Virginia who delivered a live infant in 1990-1991 and participated in the Pregnancy Risk Assessment Monitoring System. Five SES measures were evaluated: education; poverty status; Medicaid payment for delivery; Women, Infants, and Children (WIC) enrollment during pregnancy; and residential crowding. Three maternal health behaviors (smoking, delayed/no prenatal care, unintended pregnancy) were examined to assess the variation among the associations between SES measures and behaviors. Item response rates were high for all SES measures (range: 88.9%-100.0%), and there was low correlation between measures. Most of the SES measures were related to maternal health behaviors. However, the strength of association varied between each measure and behavior and was weaker for women who were younger than 20 years old or not married. In view of the multifaceted nature of SES, several measures may be needed to appropriately assess the relationship between SES and maternal health behaviors.