Development and cross-validation of a prediction equation for estimating resting energy expenditure in healthy African-American and European-American women.

OBJECTIVE: To develop, validate, and cross-validate a formula for predicting resting energy expenditure (REE) in African-American and European-American women. DESIGN: A cross-sectional study of REE in women. Participants were randomly assigned to one of two groups. One group served to develop and validate a new equation for predicting REE while the second was used to cross-validate the prediction equation. The accuracy of the equation was compared to several existing formulae. SETTING: University metabolic laboratory, Memphis, TN, USA. SUBJECTS: Healthy, premenopausal African-American and European-American women between 18 and 39 y of age. The validation sample included 239 women (age: 28.4 y, wt: 70.7 kg, body mass index (BMI): 25.2 kg/m(2), REE: 5840 kJ/day), while the cross-validation sample consisted of 232 women (age: 27.5 y, wt: 70.7 kg, BMI: 25.2 kg/m(2), REE: 5784 kJ/day). RESULTS: The prediction equation derived from the current sample, which included adjustments for ethnicity, was the only formula that demonstrated a high level of accuracy for predicting REE in both African-American and European-American women. The mean difference between REE predicted from the new formula and measured REE was 28 kJ/day (s.d.=668) for European-American women and 142 kJ/day (s.d.=584) for African-American women. CONCLUSIONS: Previous equations for predicting energy needs may not be appropriate for both African-American and European-American women due to ethnic differences in REE. A new equation that makes adjustments in predicted REE based on ethnicity is recommended for determining energy needs in these groups (Predicted REE (kJ/day)=616.93-14.9 (AGE (y))+35.12 (WT (kg))+19.83 (HT (cm))-271.88 (ETHNICITY: 1=African American; 0=European American)). SPONSORSHIP: Support for this study was provided by Grant #HL53261 from the National Heart, Lung, and Blood Institute.

Socioeconomic status, ethnicity, and environmental tobacco exposure among non-smoking females.

This study examined the relationship between socioeconomic status (SES) and environmental tobacco smoke (ETS) exposure among non-smoking females, determined which SES variable(s) were most strongly associated with ETS exposure, and examined whether the relationship between SES and ETS exposure was the same for Blacks and Whites. Participants were 404 never-smoker females recruited in the community. Independent variables included income, education, occupation, median income within zip code of participants' residence, and ethnicity. Number of days per week exposed to ETS in the past year was the dependent variable. There was a significant correlation between CO levels (parts per million, ppm) and self-reported ETS exposure (r = 0.22, p < 0.001). The mean CO level exposure was 1.81 +/- 1.19 ppm, and the mean number of days per week of ETS exposure was 4.72 +/- 4.71. The most frequent source of ETS exposure was at public places (64.4%). Although Blacks tended to report higher ETS exposure than Whites (p = 0.08), this tendency disappeared when SES indicators were entered in the model. Correlations among SES indicators were either non-significant or very modest suggesting that different SES indicators may not measure the same construct. Education was the only SES variable that was significantly associated with ETS exposure in this population. The relationship between SES and ETS exposure was similar for both Blacks and Whites. These findings suggest that education may be the most important factor to be considered when designing interventions to decrease ETS exposure among young non-smoking females (e.g., public education of the hazards of ETS exposure and awareness of existing tobacco-control laws and regulations).