Can an increase in waist circumference determine cardiovascular risk, separate from weight loss or gain?
Obesity is a predominant risk factor for both cardiovascular disease and metabolic disorders. Even a modest weight loss of about 5 to 10 percent is proven to reduce future complications. Also, a patient with diabetes will better manage their glucose levels by reducing their weight. An individual’s BMI and waist circumference are usually used to determine if they have obesity or face any adiposity-related risks. Previously, behavioral weight-loss trials regularly used waist circumference; however, they lacked correlation to weight loss’s effects on different health outcomes. This study adds data linking increases in one’s waist circumference to subsequent cardiovascular outcomes. This study connects these two regardless of weight loss or weight gain in behavioral treatment.
The Action for Health in Diabetes was a randomized controlled trial called Look AHEAD. This trial’s primary outcome was to compare the effects of intensive lifestyle and diabetes support and education on cardiovascular disease among patients with either overweight or obesity and type 2 diabetes. The secondary outcomes were done to assess the association between an individual’s change in weight, weight circumference, and cardiovascular disease outcomes. Researchers evaluated three different endpoints using cox proportional hazard regression models. All three sets were adjusted for other factors. Kaplan Meier plots by randomization were used to show the differences in event rates over follow-up. A p-value of 0.05 was used to determine significance for all of the tests.
Five hundred fifty-five participants were excluded from the study, leaving the Look AHEAD trial final total of 4,590 participants. There were 2,260 participants in the diabetes support and education arm and 2,330 participants in the intensive lifestyle intervention arm. Cardiovascular outcomes did not vary within the diabetes support and education arm. Intensive lifestyle intervention arm participants with increased waist circumference had an increased risk of primary outcomes, regardless of weight loss (hazard ratio: 1.55 [95% CI: 1.11-2.17]) or weight gain (hazard ratio: 1.76 [95% CI: 1.07-2.89]). The intensive lifestyle intervention arm participants with increased WC also had increased risk of secondary outcomes (overall P < 0.01) relative to lifestyle intervention participants who reduced both weight and waist circumference, and relative to the support and education arm participants.
It is safe to state that the findings are more evident with the secondary outcomes. A beneficial clinical conclusion cannot be drawn from the primary outcome. Future studies should be done to compare two specific lifestyle interventions concerning waist circumference. The researchers should determine if a reduction in waist circumference separate from general weight loss represents a distinct process that reduces cardiovascular risk.
- Central adipose body fat is associated with cardiometabolic disease.
- Individuals with increased waist circumference were linked to having an increased risk of cardiovascular events.
- Patients with type 2 diabetes can have cardiovascular benefits from modest weight loss.
Olson KL, Neiberg RH, Espeland MA, et al. Waist Circumference Change During Intensive Lifestyle Intervention and Cardiovascular Morbidity and Mortality in the Look AHEAD Obesity
Alexandria Bartley, PharmD. Candidate, Florida Agricultural & Mechanical University, College of Pharmacy and Pharmaceutical Sciences