Ruth E. Patterson

Design of the Women's Health Initiative clinical trial and observational study

The Womens Health Initiative (WHI) is a large and complex clinical investigation of strategies for the prevention and control of some of the most common causes of morbidity and mortality among postmenopausal women, including cancer, cardiovascular disease, and osteoporotic fractures. The WHI was initiated in 1992, with a planned completion date of 2007. Postmenopausal women ranging in age from 50 to 79 are enrolled at one of 40 WHI clinical centers nationwide into either a clinical trial (CT) that will include about 64,500 women or an observational study (OS) that will include about 100,000 women. The CT is designed to allow randomized controlled evaluation of three distinct interventions: a low-fat eating pattern, hypothesized to prevent breast cancer and colorectal cancer and, secondarily, coronary heart disease; hormone replacement therapy, hypothesized to reduce the risk of coronary heart disease and other cardiovascular diseases and, secondarily, to reduce the risk of hip and other fractures, with increased breast cancer risk as a possible adverse outcome; and calcium and vitamin D supplementation, hypothesized to prevent hip fractures and, secondarily, other fractures and colorectal cancer. Overall benefit-versus-risk assessment is a central focus in each of the three CT components. Women are screened for participation in one or both of the components--dietary modification (DM) or hormone replacement therapy (HRT)--of the CT, which will randomize 48,000 and 27,500 women, respectively. Women who prove to be ineligible for, or who are unwilling to enroll in, these CT components are invited to enroll in the OS. At their 1-year anniversary of randomization, CT women are invited to be further randomized into the calcium and vitamin D (CaD) trial component, which is projected to include 45,000 women. The average follow-up for women in either CT or OS is approximately 9 years. Concerted efforts are made to enroll women of racial and ethnic minority groups, with a target of 20% of overall enrollment in both the CT and OS. This article gives a brief description of the rationale for the interventions being studied in each of the CT components and for the inclusion of the OS component. Some detail is provided on specific study design choices, including eligibility criteria, recruitment strategy, and sample size, with attention to the partial factorial design of the CT. Some aspects of the CT monitoring approach are also outlined. The scientific and logistic complexity of the WHI implies particular leadership and management challenges. The WHI organization and committee structure employed to respond to these challenges is also briefly described.

Measurement Characteristics of the Women’s Health Initiative Food Frequency Questionnaire

PURPOSE The Womens Health Initiative (WHI) is the largest research program ever initiated in the United States with a focus on diet and health. Therefore, it is important to understand and document the measurement characteristics of the key dietary assessment instrument: the WHI food frequency questionnaire (FFQ). METHODS Data are from 113 women screened for participation in the WHI in 1995. We assessed bias and precision of the FFQ by comparing the intake of 30 nutrients estimated from the FFQ with means from four 24-hour dietary recalls and a 4-day food record. RESULTS For most nutrients, means estimated by the FFQ were within 10% of the records or recalls. Precision, defined as the correlation between the FFQ and the records and recalls, was similar to other FFQs. Energy adjusted correlation coefficients ranged from 0.2 (vitamin B12) to 0.7 (magnesium) with a mean of 0.5. The correlation for percentage energy from fat (a key measure in WHI) was 0.6. Vitamin supplement use was common. For example, almost half of total vitamin E intake was obtained from supplements. Including supplemental vitamins and minerals increased micronutrient correlation coefficients, which ranged from 0.2 (thiamin) to 0.8 (vitamin E) with a mean of 0.6. CONCLUSIONS The WHI FFQ produced nutrient estimate, that were similar to those obtained from short-term dietary recall and recording methods. Comparison of WHI FFQ nutrient intake measures to independent and unbiased measures, such as doubly labeled water estimates of energy expenditure, are needed to help address the validity of the FFQ in this population.

Diet quality index: Capturing a multidimensional behavior

OBJECTIVE Data for 5,484 adults (aged 21 years and older) who participated in the 1987-88 Nationwide Food Consumption Survey (NFCS) were used to develop an index of overall dietary intake that related to the major, diet-related, chronic diseases in the United States. The low response rate of the 1987-88 NFCS has raised concerns about potential bias, but this large data set is useful for methodologic studies and research that does not attempt to generalize the results to the US population. ANALYSES Dietary recommendations from the 1989 National Academy of Sciences publication Diet and Health were stratified into three levels of intake for scoring. Individuals who met a dietary goal were given a score of zero. Those who did not meet a goal, but had a fair diet, were given one point, and those who had a poor diet were given two points. These points were summed across eight diet variables to score the index from zero (excellent diet) to 16 (poor diet). RESULTS Lower index scores were positively associated with high intakes of other important measures of diet quality (eg, fiber, vitamin C). We found that single nutrients (such as dietary fat) were not necessarily associated with other measures of diet quality. CONCLUSION We concluded that this index ranking of overall dietary patterns was reflective of total diet quality, though substantial misclassification can result from using single nutrients or foods as indicators of diet quality.

Use Of Food Nutrition Labels is Associated with Lower Fat Intake

OBJECTIVE The Nutrition Labeling and Education Act of 1990 mandated that standardized nutrition information appear on almost all packaged foods manufactured after May 1994. This study describes the demographic and diet-related psychosocial correlates of nutrition label use, and examines the relationship between label use and diet. DESIGN/SUBJECTS Data are from a random-digit-dial telephone survey of 1,450 adult residents of Washington State. The questionnaire assessed nutrition label use, fat-related diet habits, fruit and vegetable consumption, diet-related psychosocial factors, health behavior, and demographic characteristics. STATISTICAL ANALYSES Analyses examined associations of demographic characteristics with nutrition label use; diet-related psychosocial factors and health behavior with nutrition label use, controlled for demographic characteristics; and nutrition label use with fat and fruit and vegetable intake, controlled for demographic characteristics and psychosocial factors. RESULTS Nutrition label use was significantly higher among women, residents younger than 35 years, and residents with more than a high school education. When controlled for demographic characteristics, the strongest predictors of label use were believing in the importance of eating a low-fat diet, believing in an association between diet and cancer, and being in the maintenance stage of change for adopting a low-fat diet. Label use was significantly associated with lower fat intake and, after controlling for all demographic, psychosocial, and behavioral variables, explained 6% of the variance in fat intake (P < .001). Label use was not associated with fruit and vegetable consumption. APPLICATIONS/CONCLUSION Persons successfully limiting their fat intake use nutrition labels, suggesting that the new nutrition labels are helpful. Dietetics professionals can use the results of this study to emphasize to their clients the importance of reading nutrition labels in maintaining a low-fat diet.

Stages of Change in Adopting Healthy Diets: Fat, Fiber, and Correlates of Nutrient Intake

The stages of change construct, which addresses the readiness to change, has only recently been applied to dietary behavior, such as fat consumption. This article describes the application of the stages of change construct to dietary fat and fiber consumption and examines the association of dietary stages to eating practices and related demographic and psychosocial factors in a large, geographically diverse population of workers. We present results from the baseline survey of 17,121 employees in the Working Well Trial. We assessed stage from an algorithm based on seven items and measured dietary intake with an 88-item food frequency questionnaire. Findings indicated that a greater proportion of the population has actively tried to reduce fat intake than to consume more fiber. Stage of change was associated with fat, fiber, and fruit and vegetable intake in a stepwise manner, as predicted. In multivariate analyses that controlled for demographic characteristics, stage of change predicted between 8 and 13% of the variance in dietary intake, and more than demographic variables. These findings have implications for the design of nutrition interventions and for the evaluation of intermediate outcomes.

Demographic and Psychosocial Predictors of Fruit and Vegetable Intakes Differ: Implications for Dietary Interventions

OBJECTIVE The National Cancer Institute (Rockville, Md) has launched a nationwide initiative--5 A Day for Better Health--to encourage consumption of fruits and vegetables. Because the tastes and culinary uses of fruits and vegetables differ, however, it is not known whether a general 5-A-Day message is an effective intervention strategy. This study examined whether there are differences between the demographic and psychosocial correlates of fruit and vegetable intakes. DESIGN Data are from the Washington State Cancer Risk Behavior Survey (1995-1996), a cross-sectional, random-digit-dial telephone survey representative of the adult population of Washington State. SUBJECTS/SETTING Interviews were completed with 1,450 adults. Data were collected about demographic characteristics, health status, health-related behavior, fruit and vegetable intakes, and the following diet-related psychosocial factors: beliefs, motives, barriers, attitudes, and stages of dietary change. STATISTICAL ANALYSES Multivariate linear regression analysis was used to test whether the associations of demographic characteristics and psychosocial factors with fruit intake differed from associations with vegetable intake. RESULTS In general, health status, health-related behavior, and psychosocial factors were more strongly associated with fruit intakes than vegetable intakes. For example, regular exercisers consumed 0.44 more daily servings of fruits and 0.36 more servings of vegetables than nonexercisers. Compared with those in the preaction stage of dietary change, adults in the maintenance stage consumed 0.99 more daily servings of fruits and 0.68 more servings of vegetables. Intrinsic motivations for eating a healthful diet (eg, to feel better) were strongly associated with both fruit and vegetable intakes, and these associations were stronger for fruit. Extrinsic motivations were not associated with either fruit or vegetable intakes. APPLICATIONS Dietary interventions based on a general 5-A-Day message may be more effective in increasing fruit intakes than vegetable intakes. Targeted interventions that focus specifically on vegetables are probably necessary. Intrinsic motives for eating a healthful diet should be key components of interventions to increase fruit and vegetable intakes.

Types of Alternative Medicine Used by Patients with Breast, Colon, or Prostate Cancer: Predictors, Motives, and Costs

OBJECTIVE Assess predictors and costs of various types of alternative medicine used by adult patients with cancer. DESIGN, LOCATION, SUBJECTS: Telephone survey of 356 patients with colon, breast, or prostate cancer identified from the population-based Cancer Surveillance System of western Washington. RESULTS Overall, 70.2% of patients used at least one type of alternative medicine, with 16.6% seeing alternative providers, 19.1% using mental/other therapy, and 64.6% taking dietary supplements. Compared to males, females were five times more likely to see an alternative provider and about twice as likely to use mental therapies or supplements (p < 0.05 for all). Older patients were less likely to use mental/other therapy. Higher education (but not income) was associated with use of all types of alternative medicine. Patients with multiple medical treatments were two times more likely to take dietary supplements compared to patients having only surgery (p < 0.01). Varying by the type of alternative therapy, 83%-97% of patients reported that they used alternative medicine for general health and well-being while 8% to 56% reported use for treatment of cancer. Almost all patients reported that the alternative therapy improved their well-being. Expenditures for alternative medicine averaged

Physical activity, diet, adiposity and female breast cancer prognosis: A review of the epidemiologic literature

68 per user per year, but ranged from

The Women's Health Initiative Dietary Modification Trial: Overview and Baseline Characteristics of Participants

4 to

Multivitamin use and risk of cancer and cardiovascular disease in the women's health initiative cohorts

14,659. CONCLUSIONS Given the high prevalence of use and that patients believed that alternative medicine improved their well-being, clinicians should show an open mind toward these treatment choices and encourage frank discussion. Familiarity and some knowledge regarding use of alternative medicine is important in cases where interactions between conventional and alternative medicine may occur. It is also important to identify potential patient needs for mental health support beyond conventional care and support patients who want to make healthful lifestyle changes. Longitudinal investigations are urgently needed to investigate associations of alternative medicine use with survival and quality of life in patients with cancer.