Metabolically healthy obesity and cardiovascular outcomes

Abstract   Obesity increases cardiovascular risk through a deterioration of the metabolic profile. However, obesity is not always accompanied by a worsening metabolic profile. This longitudinal study aimed to determine whether obesity with a normal metabolic profile, i.e. metabolically healthy obesity, increases the risk of cardiovascular disease. We analyzed a health insurance data of Shizuoka prefecture resident. This data includes data from annual health check-ups performed for insured persons. This study analyzed data from 168,699 individuals aged <65 years. Obesity was defined as ≥ 25 kg/m2 body mass index. Metabolically healthy was defined as ≤ 1 metabolic risk factors (high blood pressure, low high-density lipoprotein cholesterol, high low-density lipoprotein cholesterol, or high hemoglobin A1c). Incidence rate of cardiovascular diseases (stroke and myocardial infarction), and all-cause mortality identified from the insurance data were compared between clinical profile-matched metabolically healthy obesity and non-obesity groups (n = 8,644 each). Clinical parameters, namely systolic blood pressure (standard mean difference = 0.03), HDL cholesterol (0.01), LDL cholesterol (0.01), and hemoglobin A1c (0.01) did not differ among the metabolically healthy obesity and non-obesity groups. The incident rate of stroke (obesity: 9.2 per 10,000 person-years; non-obesity: 10.5; log-rank test P = 0.595), myocardial infarction (obesity: 3.7; non-obesity: 3.1; P = 0.613), and all-cause mortality (obesity: 26.6; nonobesity: 23.2; P = 0.304) also did not differ significantly among the groups even when abdominal obesity was considered in the analysis, though the population with metabolically healthy obesity reported negligibly worse metabolic profiles than the population with nonobese at the 5.6-year follow-up. Obesity, when accompanied by a healthy metabolic profile, did not increase the risk of cardiovascular outcomes and all-cause mortality. Key messages • Metabolically healthy obesity did not increase cardiovascular disease risks. • Metabolically healthy obesity was associated with worse metabolic profiles after a few years later.