Background
Recent evidence for several high income countries has suggested obesity prevalence may have plateaued since early 2000 for children and adults. Among children such improvements are more common among those from more socioeconomically advantaged families. Whether this is also the case for adults remains relatively unknown.
Methodology
Using three nationally representative surveys, the 2000 Australian Diabetes, Obesity and Lifestyle Study, the 2007 National Health Survey and the 2012 National Nutrition and Physical Activity Survey, we aimed to quantify trends in obesity (BMI≥30 kg/m2) and class II+ obesity (BMI≥35 kg/m2) among urban Australian men and women with a higher and lower education level . Variance weighted least squares regression was used to determine whether trends in these prevalence estimates improved for each education group. An interaction term, fitted between education and time, indicated whether trends significantly differed according to education group. Age was standardised to the 2007 mid-year population using the direct method.
Results
Between 2000 and 2012 there was no significant increase in the prevalence of obesity or class II+ obesity among higher educated women. Conversely, among lower educated women increases were observed for the prevalence of obesity (24% to 32%) and class II+ obesity (9% to 16%). Trends in class II+ obesity, but not overall obesity, were significantly different between higher and lower educated women. For men the prevalence of obesity and class II+ obesity significantly increased among men with a lower (23% to 28% and 4% to 6%, respectively) and higher education (13% to 25% and 3% to7%, respectively), with no significant differences between education groups.
Conclusion
We observed evidence
of a plateau in the prevalence of obesity and class II+ obesity between 2000
and 2012 among Australian women with a higher educational attainment, which was
not evident for men or women with a lower educational attainment.