Waist Size Shown to Be More Predictive of Coronary Artery Disease Than Overall Body Weight in Postmenopausal Women

Central obesity assessed by waist circumference (WC) was associated with obstructive coronary artery disease (CAD) in postmenopausal women, while overall body mass index (BMI) was not, according to a study published last week in Menopause, the journal of The North American Menopause Society.

In the study, researchers sought to investigate the association between obesity type and obstructive CAD. A total of 659 women aged older than 55 years with chest pain undergoing invasive coronary angiography in suspicion of CAD were studied. Obesity is measured through 2 assessments, BMI and WC, but prior studies have not confirmed which type of obesity is more significant in the development of CAD.

Data was derived from the prospective and nationwide registry database Korean Women’s Chest Pain Registry, which assesses the clinical characteristics and outcomes of CAD in Korean women. The angiographic findings were utilized to define obesity levels in these women:

• Obstructive CAD defined as ≥50% diameter stenosis with any major epicardial coronary artery
• Overall obesity defined as BMI ≥25 kg/m²
• Central Obesity defined as WC ≥85 cm

Research revealed that 311 (47.2%) women in the study had obstructive CAD. When measuring for incidence and BMI in participants with and without obstructive CAD, there was no significant difference in overall obesity (44.6% vs 48.5%; P = .340) or BMI (P = .373). Women with central obesity, however, exhibited a significantly higher prevalence of CAD than those without (55% vs 41%; P = .001). After conducting a multivariable analysis, central obesity was associated with obstructive CAD (odds ratio=1.61; 95% CI, 1.10-2.34; P = .013), while overall obesity was not (P = .228).

Stephanie Faubion, MD, NAMS medical director, in a statement highlighted the stark difference of fat distribution found in the study in association to CAD risk. “The findings of the study are consistent with what we know about the detrimental effects of central obesity. Not all fat is the same, and central obesity is particularly dangerous because it is associated with risk for heart disease, the number 1 killer of women,” he said.

Central obesity has been shown in the past to be more indicative of health issues, with an article posted last month correlating postmenopausal women with normal-weight central obesity to a heightened risk of mortality, cardiovascular disease, and cancer. As mentioned in the article, normal-weight women who revealed no risk in the BMI assessment were shown to exhibit significant risk of mortality for these diseases, which highlights the importance of utilizing WC.

While associations between WC and CAD were found in the study, the findings do have limitations. Researchers considered women over the age of 55 to be postmenopausal, but there is a possibility that some Korean women were still premenopausal. The additional focus solely on Korean women restricts associations to this group, which may not be applicable to other populations. Cross-sectional analysis also could not confirm a causal relationship between obesity and CAD, which warrants further investigation.

“Identifying women with excess abdominal fat, even with a normal BMI, is important so that lifestyle interventions can be implemented,” said Faubion.

Reference

Cho JH, Kim HL, Kim MA, et al. Association between obesity type and obstructive coronary artery disease in stable symptomatic postmenopausal women. [published online August 28, 2019]. Menopause. doi: 10.1097/GME.0000000000001392.