Barbara Sternfeld
Kaiser Permanente
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American Journal of Public Health | 2006
Ellen B. Gold; Alicia Colvin; Nancy E. Avis; Joyce T. Bromberger; Gail A. Greendale; Lynda H. Powell; Barbara Sternfeld; Karen A. Matthews
OBJECTIVES We investigated whether vasomotor symptom reporting or patterns of change in symptom reporting over the perimenopausal transition among women enrolled in a national study differed according to race/ethnicity. We also sought to determine whether racial/ethnic differences were explained by sociodemographic, health, or lifestyle factors. METHODS We followed 3198 women enrolled in the Study of Womens Health Across the Nation during 1996 through 2002. We analyzed frequency of vasomotor symptom reporting using longitudinal multiple logistic regressions. RESULTS Rates of vasomotor symptom reporting were highest among African Americans (adjusted odds ratio [OR]=1.63; 95% confidence interval [CI]=1.21, 2.20). The transition to late perimenopause exhibited the strongest association with vasomotor symptoms (adjusted OR = 6.64; 95% CI = 4.80, 9.20). Other risk factors were age (adjusted OR=1.17; 95% CI=1.13, 1.21), having less than a college education (adjusted OR = 1.91; 95% CI = 1.40, 2.61), increasing body mass index (adjusted OR=1.03 per unit of increase; 95% CI=1.01, 1.04), smoking (adjusted OR=1.63; 95% CI=1.25, 2.12), and anxiety symptoms at baseline (adjusted OR=3.10; 95% CI=2.33, 4.12). CONCLUSIONS Among the risk factors assessed, vasomotor symptoms were most strongly associated with menopausal status. After adjustment for covariates, symptoms were reported most often in all racial/ethnic groups in late perimenopause and nearly as often in postmenopause.
Journal of the American College of Cardiology | 2009
Karen A. Matthews; Sybil L. Crawford; Claudia U. Chae; Susan A. Everson-Rose; Mary Fran Sowers; Barbara Sternfeld; Kim Sutton-Tyrrell
OBJECTIVES This prospective study examined whether changes in traditional and novel coronary heart disease (CHD) risk factors are greater within a year of the final menstrual period (FMP), relative to changes that occur before or after that interval, in a multiethnic cohort. BACKGROUND Understanding the influence of menopause on CHD risk remains elusive and has been evaluated primarily in Caucasian samples. METHODS SWAN (Study of Womens Health Across the Nation) is a prospective study of the menopausal transition in 3,302 minority (African American, Hispanic, Japanese, or Chinese) and Caucasian women. After 10 annual examinations, 1,054 women had achieved an FMP not due to surgery and without hormone therapy use before FMP. Measured CHD risk factors included lipids and lipoproteins, glucose, insulin, blood pressure, fibrinogen, and C-reactive protein. We assessed which of 2 models provided a better fit with the observed risk factor changes over time in relation to the FMP: a linear model, consistent with chronological aging, or a piecewise linear model, consistent with ovarian aging. RESULTS Only total cholesterol, low-density lipoprotein cholesterol, and apolipoprotein B demonstrated substantial increases within the 1-year interval before and after the FMP, consistent with menopause-induced changes. This pattern was similar across ethnic groups. The other risk factors were consistent with a linear model, indicative of chronological aging. CONCLUSIONS Women experience a unique increase in lipids at the time of the FMP. Monitoring lipids in perimenopausal women should enhance primary prevention of CHD.
Menopause#R##N#Biology and Pathobiology | 2000
Mary Fran Sowers; Sybil L. Crawford; Barbara Sternfeld; David Morganstein; Ellen B. Gold; Gail A. Greendale; Denis A. Evans; Robert M. Neer; Karen A. Matthews; Sherry Sherman; Annie Lo; Gerson Weiss; Jennifer L. Kelsey
Study of Womens Health Across the Nation (SWAN) is the first national study to describe women at midlife, an understudied age group. Its multidisciplinary approach provides the opportunity to consider the contributions of both culture and biology so that one may better understand health of women. The SWAN employs a prospective design that includes sufficient pre- and postmenopausal observations to ensure the separation of menopause-related and age-related physiological changes. Other attributes include the comprehensive standardized data collection related to biological, behavioral, physiological, social, environmental, and cultural factors; specialized data collection methodologies suitable to address the monthly and yearly variation in behavioral and biological patterns; general ability to community-dwelling populations recruited from major United States population centers; sufficiently large sample size and numbers of data points to ensure reliable estimates of associations and relevant effect sizes; and inclusion of sufficient numbers of racial/ethnic minorities to provide comparative information with the non-Hispanic Caucasian population. Because of these attributes, SWAN can contribute new and substantive knowledge about womens health in general and the menopause transition in particular.
Medicine and Science in Sports and Exercise | 2000
Barbara E. Ainsworth; Barbara Sternfeld; Mark T. Richardson; Kirby L. Jackson
PURPOSE The Kaiser Physical Activity Survey (KPAS) was evaluated for test-retest reliability and comparison with direct and indirect measures of physical activity (PA) in 50 women (ages 20-60 yr) with a broad range of physical activity (PA) habits. METHODS The KPAS, an adaptation of the Baecke usual physical activity survey, was designed specifically to assess activity in women. It provides four summary activity indexes: housework/caregiving, active living habits, sports, and occupation. Summary indexes were compared against direct (Caltrac accelerometer and PA records) and indirect (cardiorespiratory fitness (VO2 peak) and percent body fat) criterion measures of PA. Participants kept detailed PA records for two, 7-d periods, separated by 1 month. Caltrac accelerometers were worn concurrently with the PA records. RESULTS Intraclass correlations for 1-month test-retest reliability were high for all KPAS indexes (r = 0.79 to 0.91, P < 0.01). Age-adjusted Spearman rho correlations between the KPAS sports/exercise and active living habits indexes were of moderate magnitude for VO2 peak (r = 0.34 to 0.76, P < 0.01) and percent body fat (r = -.30 to -0.59, P < 0.05). KPAS caregiving and occupation indexes were related to Caltrac kcal x d(-1) (r = 0.30 to 0.44, P < 0.05). Correlations between similar activities from the KPAS and PA records ranged from r = 0.03 to 0.64. Daily, habitual activities from the KPAS and PA records had the highest correlations (r > 0.28). Correlations among infrequent activities were lower (r < 0.05). CONCLUSION The KPAS demonstrated good reliability and was reasonably accurate in detecting regular housework/caregiving, occupation, sports/exercise, and active leisure activities among women with a broad range of physical activity habits.
JAMA Internal Medicine | 2009
Penny Gordon-Larsen; Janne Boone-Heinonen; Steve Sidney; Barbara Sternfeld; David R. Jacobs; Cora E. Lewis
BACKGROUND There is little research on the association of lifestyle exercise, such as active commuting (walking or biking to work), with obesity, fitness, and cardiovascular disease (CVD) risk factors. METHODS This cross-sectional study included 2364 participants enrolled in the Coronary Artery Risk Development in Young Adults (CARDIA) study who worked outside the home during year 20 of the study (2005-2006). Associations between walking or biking to work (self-reported time, distance, and mode of commuting) with body weight (measured height and weight); obesity (body mass index [BMI], calculated as weight in kilograms divided by height in meters squared, >or= 30); fitness (symptom-limited exercise stress testing); objective moderate-vigorous physical activity (accelerometry); CVD risk factors (blood pressure [oscillometric systolic and diastolic]); and serum measures (fasting measures of lipid, glucose, and insulin levels) were separately assessed by sex-stratified multivariable linear (or logistic) regression modeling. RESULTS A total of 16.7% of participants used any means of active commuting to work. Controlling for age, race, income, education, smoking, examination center, and physical activity index excluding walking, men with any active commuting (vs none) had reduced likelihood of obesity (odds ratio [OR], 0.50; 95% confidence interval [CI], 0.33-0.76), reduced CVD risk: ratio of geometric mean triglyceride levels (trig(active))/(trig(nonactive)) = 0.88 (95% CI, 0.80 to 0.98); ratio of geometric mean fasting insulin (FI(active))/(FI(nonactive)) = 0.86 (95% CI, 0.78 to 0.93); difference in mean diastolic blood pressure (millimeters of mercury) (DBP(active)) - (DBP(nonactive)) = -1.67 (95% CI, -3.20 to -0.15); and higher fitness: mean difference in treadmill test duration (in seconds) in men (TT(active)) - (TT(nonactive)) = 50.0 (95% CI, 31.45 to 68.59) and women (TT(active)) - (TT(nonactive)) = 28.77 (95% CI, 11.61 to 45.92). CONCLUSIONS Active commuting was positively associated with fitness in men and women and inversely associated with BMI, obesity, triglyceride levels, blood pressure, and insulin level in men. Active commuting should be investigated as a modality for maintaining or improving health.
American Journal of Public Health | 2006
Wenjun Li; Theresa H.M. Keegan; Barbara Sternfeld; Stephen Sidney; Charles P. Quesenberry; Jennifer L. Kelsey
OBJECTIVES Although risk factors for indoor falls among older individuals have been well studied, little is known about the etiology of outdoor falls. We examined risk factors for outdoor falls among middle-aged and older adults. METHODS We analyzed data on the most recent fall during the past year among participants aged 45 years and older in the control group (N=2193) of a case-control study of fractures. The study was conducted at 5 Northern California Kaiser Permanente Medical Centers between 1996 and 2001. RESULTS Falls occurred outdoors more often than indoors among most age groups. Study participants who reported more leisure-time physical activity had a higher risk for outdoor falls, and participants who were in poorer health had a greater risk for indoor falls. Most outdoor falls (73%) were precipitated by environmental factors, such as uneven surfaces and tripping or slipping on objects, and usually occurred on sidewalks, curbs, and streets. Walking (47.3%) was the most common fall-related activity. CONCLUSIONS Outdoor falls among adults aged 45 years and older were frequently attributable to modifiable environmental factors. With the widespread promotion of active lifestyles among older people, improvements in their outdoor environment are urgently needed.
Medicine and Science in Sports and Exercise | 1995
Barbara Sternfeld; Charles P. Quesenberry; Brenda Eskenazi; Lawrence A. Newman
To investigate the effects of participation in aerobic exercise on pregnancy outcome, 388 women (mean age = 31.7, range = 18-42) were followed from a mean 16.5-wk gestation through delivery. Frequency, duration, and mode of aerobic exercise prior to conception and during the first trimester were determined by in-person interviews. Activity patterns during the second and third trimesters were assessed by telephone interviews. For each time period, women were categorized into one of the following exercise groups: Level I = aerobic exercise, excluding vigorous walking, at least three times a week for at least 20 min a time; Level II = aerobic exercise at least three times a week and 20 min at a time, if and only if vigorous walking is included; Level III = aerobic exercise less than three times a week, 20 min a time; and Level IV = aerobic exercise less than once a week. Mean birthweight was statistically unrelated to level of exercise preconceptionally or in any trimester. Gestational age, weight gain, and other pregnancy outcomes were also unassociated with exercise level. However, pregnancy symptoms were inversely associated with level of exercise; women who exercised more earlier in pregnancy reported fewer discomforts later in pregnancy (P = 0.01). These data suggest that participation in aerobic exercise during pregnancy at a level great enough to produce or maintain a training effect does not adversely affect birthweight or other maternal and infant outcomes but may be associated temporally with fewer perceived pregnancy-associated discomforts.
Cancer Prevention Research | 2011
Melinda L. Irwin; Anne McTiernan; JoAnn E. Manson; Cynthia A. Thomson; Barbara Sternfeld; Marcia L. Stefanick; Jean Wactawski-Wende; Lynette L. Craft; Dorothy S. Lane; Lisa W. Martin; Rowan T. Chlebowski
Although studies have shown that physically active breast cancer survivors have lower all-cause mortality, the association between change in physical activity from before to after diagnosis and mortality is not clear. We examined associations among pre- and postdiagnosis physical activity, change in pre- to postdiagnosis physical activity, and all-cause and breast cancer–specific mortality in postmenopausal women. A longitudinal study of 4,643 women diagnosed with invasive breast cancer after entry into the Womens Health Initiative study of postmenopausal women. Physical activity from recreation and walking was determined at baseline (prediagnosis) and after diagnosis (assessed at the 3 or 6 years post-baseline visit). Women participating in 9 MET-h/wk or more (∼3 h/wk of fast walking) of physical activity before diagnosis had a lower all-cause mortality (HR = 0.61; 95% CI, 0.44–0.87; P = 0.01) compared with inactive women in multivariable adjusted analyses. Women participating in ≥9 or more MET-h/wk of physical activity after diagnosis had lower breast cancer mortality (HR = 0.61; 95% CI, 0.35–0.99; P = 0.049) and lower all-cause mortality (HR = 0.54; 95% CI, 0.38–0.79; P < 0.01). Women who increased or maintained physical activity of 9 or more MET-h/wk after diagnosis had lower all-cause mortality (HR = 0.67; 95% CI, 0.46–0.96) even if they were inactive before diagnosis. High levels of physical activity may improve survival in postmenopausal women with breast cancer, even among those reporting low physical activity prior to diagnosis. Women diagnosed with breast cancer should be encouraged to initiate and maintain a program of physical activity. Cancer Prev Res; 4(4); 522–9. ©2011 AACR.
International Journal of Obesity | 2000
Kathryn H. Schmitz; David R. Jacobs; A. Leon; Pamela J. Schreiner; Barbara Sternfeld
BACKGROUND: Hypothesis 1—sustained changes in physical activity are inversely related to changes in body weight. Hypothesis 2—those who attenuate weight gain because of a temporary increase in physical activity (PA) may maintain a lower body weight over time.METHODS: Data were from the Coronary Artery Risk Development in Young Adults (CARDIA) Study, a cohort of black and white men and women, aged 18–30 y at baseline, who attended up to five examinations over a 10 y period (n=5115 at baseline). Longitudinal associations between physical activity and body weight changes were assessed, adjusting for secular trend, age, clinic site, education, smoking, alcohol intake, parity, percentage energy intake from fat, and changes in these variables over time. For hypothesis 1, concurrent associations of physical activity and body weight changes were examined. For hypothesis 2, we explored whether weight gain attenuation associated with increased PA during the initial 2–3 y of follow-up was sustained over 5 y. The study 2 analyses were conducted with three separate 5 y intervals: baseline to year 5 (n=3641), years 2–7 (n=3160), and years 5–10 (n=2617).RESULTS: Hypothesis 1—change in physical activity was inversely associated with change in body weight within all four race and sex sub-groups (P<0.005). The predicted weight change associated with change in physical activity was four to five times larger in participants who were overweight compared with those who were not were overweight at baseline. Hypothesis 2—an increase in physical activity during 2–3 y of follow-up was associated with an attenuation of weight gain that was sustained through 5 y of follow-up whether or not the physical activity increase was maintained during the later years. This finding persisted whether the starting point for the 5 y follow-up was year 2, year 5 or baseline (women only). Comparing participants who increased physical activity with those who decreased physical activity in the first 2–3 y of follow-up (eg by at least 2 h per week of stationary cycling for at least 6 months per year), the mean 5 y weight gain attenuation ranged from 0.8 to 2.8 kg.CONCLUSIONS: The results of these analyses support the need for public health messages for promoting increased physical activity for weight maintenance and attenuation of age-related weight gain, especially for higher weight sub-populations.
Cancer Epidemiology, Biomarkers & Prevention | 2009
Barbara Sternfeld; Erin Weltzien; Charles P. Quesenberry; Adrienne Castillo; Marilyn L. Kwan; Martha L. Slattery; Bette J. Caan
Introduction: Identifying modifiable factors that reduce the risk of recurrence and improve survival in breast cancer survivors is a pressing concern. The purpose of this study was to examine the association of physical activity following diagnosis and treatment with the risk of breast cancer recurrence and mortality and all-cause mortality in women with early-stage breast cancer. Materials and Methods: The sample consisted of 1,970 women from the Life After Cancer Epidemiology study, a prospective investigation of behavioral risk factors and health outcomes. Self-reported frequency and duration of work-related, household and caregiving, recreational, and transportation-related activities during the six months prior to enrollment were assessed. Outcomes were ascertained from electronic or paper medical charts. Hazard ratios and 95% confidence intervals were estimated from delayed entry Cox proportional hazards models. Results: Although age-adjusted results suggested that higher levels of physical activity were associated with reduced risk of recurrence and breast cancer mortality (P for trend = 0.05 and 0.07, respectively for highest versus lowest level of hours per week of moderate physical activity), these associations were attenuated after adjustment for prognostic factors and other confounding variables (P for trend = 0.36 and 0.26). In contrast, a statistically significant protective association between physical activity and all-cause mortality remained in multivariable analyses (hazard ratio, 0.66; 95% confidence interval, 0.42-1.03; P for trend = 0.04). Conclusions: These findings do not support a protective effect of physical activity on breast cancer recurrence or mortality but do suggest that regular physical activity is beneficial for breast cancer survivors in terms of total mortality. (Cancer Epidemiol Biomarkers Prev 2009;18(1):87–95)