Similarity in Percent Body Fat Between White and Vietnamese Women: Implication for a Universal Definition of Obesity
ABSTRACT It has been widely assumed that for a given BMI, Asians have higher percent body fat (PBF) than whites, and that the BMI threshold for defining obesity in Asians should be lower than the threshold for whites. This study sought to test this assumption by comparing the PBF between US white and Vietnamese women. The study was designed as a comparative cross-sectional investigation. In the first study, 210 Vietnamese women ages between 50 and 85 were randomly selected from various districts in Ho Chi Minh City (Vietnam). In the second study, 419 women of the same age range were randomly selected from the Rancho Bernardo Study (San Diego, CA). In both studies, lean mass (LM) and fat mass (FM) were measured by dual-energy X-ray absorptiometry (DXA) (QDR 4500; Hologic). PBF was derived as FM over body weight. Compared with Vietnamese women, white women had much more FM (24.8 +/- 8.1 kg vs. 18.8 +/- 4.9 kg; P < 0.0001) and greater PBF (36.4 +/- 6.5% vs. 35.0 +/- 6.2%; P = 0.012). However, there was no significant difference in PBF between the two groups after matching for BMI (35.1 +/- 6.2% vs. 35.0 +/- 5.7%; P = 0.87) or for age and BMI (35.6 +/- 5.1% vs. 35.8 +/- 5.9%; P = 0.79). Using the criteria of BMI >/=30, 19% of US white women and 5% of Vietnamese women were classified as obese. Approximately 54% of US white women and 53% of Vietnamese women had their PBF >35% (P = 0.80). Although white women had greater BMI, body weight, and FM than Vietnamese women, their PBF was virtually identical. Further research is required to derive a more appropriate BMI threshold for defining obesity for Asian women.
- SourceAvailable from: PubMed Central[show abstract] [hide abstract]
ABSTRACT: Vitamin D deficiency may be an indicator of poor prognosis in patients with breast cancer before surgery. We investigated the association between serum vitamin D concentration and breast cancer prognosis according to intrinsic cancer subtypes. From June to December 2006, serum 25-OHD was measured in 310 Korean women with breast cancer who were treated at the Asan Medical Center, Korea. Clinicopathologic data were examined to determine the prognostic effects of serum 25-OHD. Expression of estrogen receptor (ER), progesterone receptor (PR), and epidermal growth factor receptor 2 (Her2) were measured using tissue microarrays. Patients were classified with luminal A, luminal B, Her2-enriched, or basal-like subtypes of breast cancer. Mean patient age was 48.7 years, and mean serum 25-OHD concentration was 31.4 ± 16.1 ng/ml. The 25-OHD levels were deficient (< 20 ng/ml) in 75 patients (24.2%), insufficient (20-29 ng/ml) in 95 (30.6%), and sufficient (30-150 ng/ml) in 140 (45.2%). Women with deficient 25-OHD levels were at increased risk of recurrence compared with those with sufficient vitamin D levels (P = 0.002). The 25-OHD concentration was inversely associated with prognosis of patients with cancer of the luminal A (P = 0.012) and luminal B subtypes (P =0.023), but not with the prognosis of patients with Her2/neu-enriched (P = 0.245) or triple-negative (P = 0.879) cancer subtypes. This association remained valid after adjustment for age, tumor size, nodal status, and estrogen receptor status (hazards ratio = 3.97; 95% confidence interval = 1.77-9.61). Vitamin D deficiency may be associated with poor outcomes in patients with luminal-type breast cancer.Annals of Surgical Oncology 07/2011; 18(7):1830-6. · 4.12 Impact Factor