‘Metabolically healthy obese’ have elevated CV risk
MedWire News: Overweight and obesity are associated with an increased risk for cardiovascular disease (CV) and mortality even in the absence of the metabolic syndrome, study findings show.
Writing in the journal Circulation, the researchers say their data refute the notion that overweight and obesity without the metabolic syndrome (known as the “metabolically healthy obese” [MHO] phenotype) are benign conditions.
Johan Ärnlöv (Uppsala University, Sweden) and team investigated associations among body mass index (BMI) categories and metabolic syndrome and the risk for CV disease and death in middle-aged men.
Their dataset was derived from the Uppsala Longitudinal Study of Adult Men, a community-based study of 1758 healthy men who were assessed for CV risk factors at the age of 50 years.
During a median follow-up of 30 years, 681 participants experienced major CV events (ie, CV death or hospitalization for acute myocardial infarction, ischemic stroke, or heart failure).
The risk for such events rose in line with increasing BMI categories at baseline, Ärnlöv et al report. Furthermore, in each BMI category, the risk for major CV events was higher in the presence of the metabolic syndrome or insulin resistance than in their absence, even after adjustment for multiple baseline confounders.
A similar pattern was seen for total mortality and CV mortality, with the risks for both endpoints rising in line with higher BMI categories and being higher in the presence than the absence of the metabolic syndrome or insulin resistance.
In secondary analyses, obesity was associated with an increased risk for noncardiovascular death and for cancer compared with normal-weight participants, regardless of the presence or absence of the metabolic syndrome.
Commenting, Ärnlöv et al say their data do not support the existence of an MHO phenotype and instead indicate that both overweight and obesity per se are associated with an increased risk for CV events and death.
“Given the favorable metabolic profile of MHO individuals, the benefits of weight loss in this subgroup have been questioned. In fact, some investigators have even suggested that weight loss in these individuals potentially could be harmful,” the authors remark.
“However, because the present data show that the overweight and obese are at higher CV risk regardless of metabolic status, the potential benefits of diagnosing MHO in clinical practice appear limited.”
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By Joanna Lyford