Inconsistencies Observed in Defining Metabolic Syndrome As Risk Factor for PAD

Despite previous research showing metabolic syndrome increases the risk of cardiovascular events and death, the extent of metabolic syndrome’s association with the risk of developing peripheral arterial disease (PAD) is still unknown.

Led by Jared Fernandez-Morales, Universidad Peruana Unión, a team of investigators evaluated metabolic syndromes risk factor for the development of PAD, observing inconsistencies in the association between the 2 factors.

The study was presented at the The Metabolic Institute of America (TMIOA) 2021 World Congress Insulin Resistance Diabetes & Cardiovascular Disease (WCIRDC) Meeting.

The Study

Fernandez-Morales and colleagues conducted a systematic review of 4 databases including PubMed, Web of Science, Scopus, and Embase throughout March 2021.

Cohort studies in the review evaluated the risk of PAD in patients with and without metabolic syndrome. The studies reported measures including relative risk (RR), odds ratio (OR), and hazard ratio (HR).

The study used a random-effects model in order to conduct meta-analysis of effect measures. They noted individual analyses were then performed according to the diagnostic creation used for metabolic syndrome.

Findings

Out of a total of 1007 studies identified after eliminating duplicates, investigators included 7 studies in the review, consisting of 43,824 participants. Most studies were conducted in the general population, while the follow-up time of all the studies were longer than 9 years.

Data show all studies using RR found an association between metabolic syndrome and the development of PAD, but one study (RR: 1.31, 95% CI, 1.03 - 1.59; l² 15.6%)

In a meta-analysis of 2 studies that presented adjusted RRs and used the classification for metabolic syndrome, they found an association between metabolic syndrome and the development of PAD (RR: 1.31; 95% CI, 1.03 - 1.59, l² 15.6%).

However, there was no evidence of an association between both variables in the studies that used HR, aside from a single study.

Additionally, investigators noted the most important difference observed showed that none of the studies that found a significant association adjusted for the diabetes variable, while studies that used HR and adjusted for diabetes found no association. They continued to suggest that diabetes may be the true risk factor in development, not metabolic syndrome.

Takeaways

The study concluded that although there was no clear evidence that metabolic syndrome is a risk factor for PAD, investigators recommended period control examinations due to 7% of patients with metabolic syndrome having asymptomatic PAD.

“In addition, efforts should be made to reduce the risk factors identified in these patients to avoid the progression of atherosclerosis and insulin resistance, since this population has a 5 to 10 times greater risk of developing diabetes and twice the risk of developing cardiovascular disease in 5 years,” investigators wrote.

“Metabolic syndrome as a risk factor for peripheral artery disease: a systematic review and meta-analysis,” was published online by WCIRDC.