Recovery from metabolic syndrome reduces cardiovascular risk, Korean study finds
The large retrospective study found that hypertension was the metabolic syndrome component with the largest associated increase in risk for a major cardiovascular event.
Patients who recovered from the metabolic syndrome had significantly lower cardiovascular risk than those who had it chronically, according to a recent Korean study.
The retrospective study used the National Health Insurance Database of Korea to analyze more than 9 million patients who received national health screenings from 2009 to 2014. They were categorized by their status with regard to the metabolic syndrome: chronic (n=1,486,485), newly developed (n=587,088), recovered (n=538,806), and free of the condition (n=6,940,663). The study's primary outcome was the occurrence of major adverse cardiovascular events (MACE), including acute myocardial infarction, revascularization, and acute ischemic stroke. Results were published by Annals of Internal Medicine on Nov. 26.
At a median follow-up of 3.54 years, the group that had recovered from the metabolic syndrome had a MACE incidence rate of 4.55 per 1,000 person-years, which was significantly lower than the 8.52 per 1,000 person-years found in the chronic metabolic syndrome group (adjusted incidence rate ratio [IRR], 0.85 [95% CI, 0.83 to 0.87]). The group that developed the condition during follow-up had significantly higher MACE risk than those who never had it (incidence rates, 6.05 vs. 1.92 per 1,000 person-years; adjusted IRR, 1.36 [95% CI, 1.33 to 1.39]). Among the metabolic syndrome components, change in hypertension status was associated with the largest difference in MACE risk.
The differences in risk by metabolic syndrome status remained significant even after adjustment for body mass index, comorbidities, and metabolic syndrome severity, suggesting that the benefit from recovery and harm from development of the condition are independent of these individual factors, the authors said. The results emphasize the potential clinical importance of elevated blood pressure compared to other metabolic syndrome components, they also noted. Despite their improvements in comparison to the group with chronic metabolic syndrome, the patients who recovered did have higher MACE risk than those who were always free of it, suggesting that the reversal of damage may take longer than the study follow-up, the authors said.
Limitations of the study include its retrospective design, short follow-up, and evaluation of patients in only one country, which may limit generalizability. “Further trials with population-scale interventions to reduce the burden of MACE by preventing or reducing MetS [metabolic syndrome] are warranted to confirm the benefits of recovery from or prevention of MetS,” the authors concluded.