PubMed Health⌕ Search

Biomedical subjects

S Kumanyika

Publications and source records attributed to S Kumanyika.

At least 19 recordsLinked to original sources

Environmental temperature during gestation and body mass index in adolescence: new etiologic clues?

OBJECTIVE: Being born during certain parts of the year is linked to the presence of obesity in later years. Animal studies suggest that environmental temperature during fetal development may be one aspect of the link to later weight status, but this relationship has not been extensively studied in humans. The present study investigates whether environmental temperature during different stages of human gestation is associated with body mass index (BMI) during late adolescence. METHODS: Questionnaire data were collected from adolescents (n=578; ages 15-19 y) attending public schools in a mid-Atlantic US city. Pearson correlations were used to assess association of BMI with mean environmental temperature (from meteorological records) during trimesters of intrauterine development and at birth. RESULTS: BMI was significantly correlated with environmental temperatures in the second and third trimester, but only among female African Americans. Among females, those 'at risk for overweight' or overweight (BMI >85th percentile) tended to be born during periods of warmer average environmental temperatures (>13.2 degrees C). However, this effect was reliable only among African American females (relative risk=2.51, CI 1.07-5.91). A similar, non-significant tendency emerged among Caucasian females, but there was no such effect in males. CONCLUSIONS: Environmental temperatures during pregnancy and at birth are associated with the likelihood that African American females become overweight as adolescents. Possible biological and dietary mechanisms for this finding are discussed.

Adolescent↗

Statistical issues in analyzing 24-hour dietary recall and 24-hour urine collection data for sodium and potassium intakes.

Dietary recalls and urine assays provide different metrics for assessing sodium and potassium intakes. Means, variances, and correlations of data obtained from these two modes of measurement differ. Pooling of these data is not straightforward, and results from studies employing the different modes may not be comparable. To explore differences between these metrics, the authors used data from the Trial of Nonpharmacologic Intervention in the Elderly (TONE), which included repeated standardized 24-hour dietary recalls and 24-hour urine collections administered over 3 years of follow-up, to estimate sodium and potassium intakes. The authors examined data from 341 control participants assigned to usual care that were collected between August 1992 and December 1995. Dietary recalls yielded estimates of sodium intake that averaged 22% less than those from urine assays and estimates of potassium intake that averaged 16% greater than those from urine assays. Sodium intake estimates were less repeatable (r = 0.22 for diet; r = 0.30 for urine) than potassium intake estimates (r = 0.49 for diet; r = 0.50 for urine), making relations with outcomes more difficult to characterize. Overall, the performance of the two measurement modes was fairly similar across demographic subgroups. Errors in separate estimations of long term sodium and potassium intakes using short term data were strongly correlated, more strongly than the underlying long term intakes of these electrolytes. Because of the correlated measurement error, estimated regression coefficients for linear models including both electrolytes as predictors may be confounded such that the separate relations between these nutrients and outcomes such as blood pressure cannot be reliably estimated by common analytical strategies.

Aged↗

Lifestyle interventions influence relative errors in self-reported diet intake of sodium and potassium.

PURPOSE: To characterize the distribution of errors in self-reported sodium and potassium dietary intakes relative to more objective urine measures among participants receiving lifestyle interventions. METHODS: We analyzed longitudinal data from 900 individuals with hypertension who had been enrolled in a randomized controlled clinical trial to establish whether usual care or three lifestyle interventions (weight loss, sodium reduction, and combined weight loss and sodium reduction) could effectively substitute for phamacotherapy. Repeated standardized 24-hour diet recalls and 24-hour urine collections were collected over up to three years of follow-up to estimate sodium and potassium intakes. By contrasting self-reported and urine-based sodium and potassium data collected before and during interventions, we examined the relative impact of intervention assignment on estimated intakes, repeatability, and multivariate measurement error. RESULTS: Relative to urine-based measures, mean self-reported sodium intakes were biased about 10% lower among participants assigned to combined weight loss and sodium reduction, but were unaffected by the other interventions. The repeatability of self-report measures increased slightly with time, particularly among participants assigned to sodium interventions. Errors in self-reported sodium and potassium intakes were correlated before the start of the intervention, but became uncorrelated among individuals assigned to sodium restriction interventions. CONCLUSIONS: Lifestyle interventions may influence not only diet intake, but also the measurement of diet intake.

Aged↗

Confidence of health professionals in public health approaches to obesity prevention.

OBJECTIVE: To assess the views of professionals working in the obesity field on the potential usefulness and feasibility of implementing different types of public health prevention strategies. METHOD: A questionnaire listing 20 public health strategies was mailed to pre-registrants of an international obesity prevention symposium. Respondents were asked to rate how useful and how feasible they felt each of the listed actions would be for the prevention of obesity in their home countries. The list included education-based strategies aimed at changing individual behaviour as well as more radical measures aimed at reducing population exposure to obesity-promoting factors in the environment. RESULTS: A 32% response was obtained. Education-based strategies were seen to be both useful and feasible. Less confidence was expressed in strategies aimed at changing the environment. CONCLUSION: People working in the obesity field tend to feel most comfortable with education-based prevention strategies. Implementation of environment-based strategies needed to encourage and support behaviour change may require the involvement of people from relevant sectors outside the obesity field.

Attitude of Health Personnel↗

Sodium reduction and weight loss in the treatment of hypertension in older persons: a randomized controlled trial of nonpharmacologic interventions in the elderly (TONE). TONE Collaborative Research Group.

CONTEXT: Nonpharmacologic interventions are frequently recommended for treatment of hypertension in the elderly, but there is a paucity of evidence from randomized controlled trials in support of this recommendation. OBJECTIVE: To determine whether weight loss or reduced sodium intake is effective in the treatment of older persons with hypertension. DESIGN: Randomized controlled trial. PARTICIPANTS: A total of 975 [corrected] men and women aged 60 to 80 years with systolic blood pressure lower than 145 mm Hg and diastolic blood pressure lower than 85 mm Hg while receiving treatment with a single antihypertensive medication. SETTING: Four academic health centers. INTERVENTION: The 585 obese participants were randomized to reduced sodium intake, weight loss, both, or usual care, and the 390 nonobese participants were randomized to reduced sodium intake or usual care. Withdrawal of antihypertensive medication was attempted after 3 months of intervention. MAIN OUTCOME MEASURE: Diagnosis of high blood pressure at 1 or more follow-up visits, or treatment with antihypertensive medication, or a cardiovascular event during follow-up (range, 15-36 months; median, 29 months). RESULTS: The combined outcome measure was less frequent among those assigned vs not assigned to reduced sodium intake (relative hazard ratio, 0.69; 95% confidence interval [CI], 0.59-0.81; P<.001) and, in obese participants, among those assigned vs not assigned to weight loss (relative hazard ratio, 0.70; 95% CI, 0.57-0.87; P<.001). Relative to usual care, hazard ratios among the obese participants were 0.60 (95% CI, 0.45-0.80; P<.001) for reduced sodium intake alone, 0.64 (95% CI, 0.49-0.85; P=.002) for weight loss alone, and 0.47 (95% CI, 0.35-0.64; P<.001) for reduced sodium intake and weight loss combined. The frequency of cardiovascular events during follow-up was similar in each of the 6 treatment groups. CONCLUSION: Reduced sodium intake and weight loss constitute a feasible, effective, and safe nonpharmacologic therapy of hypertension in older persons.

Aged↗

Data-based approach for developing a physical activity frequency questionnaire.

Measurement of total energy expenditure may be crucial to an understanding of the relation between physical activity and disease and in order to frame public health intervention. To devise a self-administered physical activity frequency questionnaire (PAFQ), the following data-based approach was used. A 24-hour recall was administered to a random sample of 919 adult residents of Geneva, Switzerland. The data obtained were used to establish the list of activities (and their median duration) that contributed to 95% of the energy expended, separately for men and women. Activities that were trivial for the whole sample but that contributed to > or = 10% of an individual's energy expenditure were also selected. The final PAFQ lists 70 activities or group of activities with their typical duration. About 20 minutes are required for respondents to indicate the number of days and the number of hours per day that they performed each activity. The PAFQ method was validated against a heart rate monitor, a more objective method. The total energy estimated by the PAFQ in 41 volunteers correlated well (r = 0.76) with estimates using a heart rate monitor. The authors conclude that the design of their self-administered physical activity frequency questionnaire based on data from 24-hour recall appeared to accurately estimate energy expenditure.

Adult↗

Pilot study to enhance start-up of a multicenter nutrition intervention trial.

Multicenter trials are important for answering questions that require large numbers of subjects. Such trials require standardized implementation of behavioral change programs across diverse populations, regions, and staff. Researchers involved with the Trial of Nonpharmacologic Interventions in the Elderly conducted a 17-week pilot study of their most complex intervention (combined weight and sodium reduction) before actual start-up of the main study. This allowed staff to rehearse implementing the program and to identify and address intervention and standardization issues. Registered dietitians in 4 US communities recruited 28 participants for the pilot study, using eligibility criteria similar to those for the main trial. Participant evaluations reflected high satisfaction with the program materials and overall approach. Minor protocol changes suggested by results of the pilot study were made easily in time for start-up of the main study. Reductions in weight and sodium intake were less than targeted but were sufficient to suggest that the intervention would be effective under optimal conditions. This partial achievement of goals in the pilot study underscored the need to allow for a learning curve, for without it standardization and outcomes of the main study would be compromised.

Aged↗

Literacy assessment in a cardiovascular nutrition education setting.

We assessed functional literacy of hypercholesterolemic or hypertensive African Americans (n = 339) prior to their participation in a nutrition education program. A word pronunciation and recognition test using 20 common cardiovascular or nutrition terms was first developed based on correlations with standardized reading achievement test scores, then administered to program participants. Nearly half (48%) had word recognition scores equivalent to a < or = 8th grade reading level. Lower scores were associated with less education, lower income, unemployment, heavier work activity if employed, less healthy diets, history of heart disease or diabetes, and higher depression scores (all P < 0.01); several of these associations were independent of education. The educational materials were geared to a 5th to 8th grade reading level. However, when both audiotaped and printed instruction were provided, individuals with reading scores < or = 8th grade preferentially used the tapes. This brief and relatively unobtrusive literacy assessment may help to identify persons who can benefit most from audiovisual approaches to cardiovascular nutrition education.

Adult↗

Carrying the burden of cardiovascular risk in old age: associations of weight and weight change with prevalent cardiovascular disease, risk factors, and health status in the Cardiovascular Health Study.

Measured weight in old age, reported weight at age 50 y, and weight change from age 50 y to old age were studied in association with prevalent cardiovascular disease (CVD), CVD risk factors, and health status in a population of 4954 men and women aged > or = 65 y in the Cardiovascular Health Study (CHS). Heavier weight (i.e., generally weight in the fourth quartile for the cohort) at age 50 y was more closely associated with prevalent CVD than was current weight, with these associations stronger in women than in men. Heavier current weight and heavier weight at age 50 y were associated with cardiovascular risk factors, including higher blood pressure, lower high-density-lipoprotein cholesterol, and higher fasting insulin. Heavier weight at both time points was related to mobility problems in both men and women and to lower current physical activity levels; among women, strong associations were also seen with lower education and current income. Remaining within 10% of reported weight at age 50 y was associated with better health status as measured by reported health, mobility difficulty, number of medications, and prevalent CVD in men. Paradoxically, most cardiovascular risk factors were lowest for weight losers despite an association of weight loss with poorer health. In this cohort of persons aged > or = 65 y, heavier weight was associated with CVD and CVD risk factors, suggesting that prevention of overweight may prove beneficial in improving cardiovascular risk in older persons. Weight stability from age 50 y to old age was associated with better health status than was weight gain or loss.

Aged↗