Urinary Bisphenol A Levels and Measures of Obesity: Results from the National Health and Nutrition Examination Survey 2003–2008

Abstract

Bisphenol A (BPA) is a widely used chemical. We examined the association between urinary BPA levels and obesity in the National Health and Nutritional Examination Survey (NHANES) 2003–2008. The main outcome of interest was obesity defined as (1) body mass index (BMI) ≥ 30 Kg/m2 and (2) waist circumference (WC) ≥ 102 cm in men and ≥ 88 cm in women. Urinary BPA levels were examined in quartiles. Overall, we observed a positive association between increasing levels of urinary BPA and both measures of obesity, independent of potential confounding factors including, smoking, alcohol consumption, and serum cholesterol levels. Compared to quartile 1 (referent), the multivariate-adjusted odds ratio (95% confidence interval) associated with quartile 4 for BMI-based obesity was 1.69 (1.30–2.20); P-trend < 0.0001 and for WC-based obesity was 1.59 (1.21–2.09); P-trend = 0.0009. This association between BPA and both measures of obesity was consistently present across gender and race-ethnic groups (all P-trend < 0.05). Elevated levels of urinary BPA are associated with measures of obesity independent of traditional risk factors. This association is consistently present across gender and race-ethnic groups. Future prospective studies are needed to confirm or disprove this finding.

Bisphenol A exposure and associations with obesity among adults: a critical review

“…Table 1 summarizes the studies and their findings. Thirteen studies were cross-sectional (62)(63)(64)67,68,(71)(72)(73)(75)(76)(77)(78) , two were case-control (65,70) and two were prospective cohort studies (66,74) , but all data analyses were crosssectional. One of the cohort studies did prospectively evaluate rate of weight change, but only evaluated the association between BMI and urinary BPA levels at baseline (74) .…”

“…The studies were conducted in the USA (n 5) (62,63,70,74,77) , Republic of Korea (n 5) (71,72,75,76,78) , China (n 2) (64,67) , Italy (n 2) (65,66) , Japan (n 2) (68,73) , Sweden (n 1) (79) and the UK (n 1) (70) . For six of the articles, body composition (BMI, WC and/or weight) was the primary outcome of interest (62)(63)(64)67,71,74) . Seven studies included only women (65,67,69,73,74,77,78) , nine of the studies were in general adult populations (62)(63)(64)66,67,70,71,75,76) , one study included men and women ≥60 years (72) and another included only 70-year-old men and women (79) .…”

“…For six of the articles, body composition (BMI, WC and/or weight) was the primary outcome of interest (62)(63)(64)67,71,74) . Seven studies included only women (65,67,69,73,74,77,78) , nine of the studies were in general adult populations (62)(63)(64)66,67,70,71,75,76) , one study included men and women ≥60 years (72) and another included only 70-year-old men and women (79) .…”

“…Six studies measured serum BPA levels; four using a competitive ELISA (65,68,73,78) , one using HPLC paired with an electrochemical detector (77) and one using LC and tandem MS (LC-MS/MS) (79) . Ten studies measured total BPA in spot urine samples (62)(63)(64)67,(70)(71)(72)(74)(75)(76) , one study used the geometric mean for two spot samples collected during the same in vitro fertilization cycle (69) and one study measured total BPA in a 24 h urine sample (66) . Urinary BPA levels were measured using GC-MS (63) and/or HPLC and tandem MS (HPLC-MS/MS) (62)(63)(64)66,67,71,72,74) .…”

“…Studies that presented duplicate data from the same study population from an already included study were excluded. In each case, the article where BMI was a primary outcome of interest was included in the review (62)(63)(64) . Two articles evaluated US National Health and Nutrition Examination Survey (NHANES) data with BMI as the primary outcome.…”