Epidemiological characteristics of metabolic phenotypic heterogeneity in adults with obesity in Shaanxi province

  Objective  To examine epidemic characteristics of obesity metabolic phenotype heterogeneity among urban adults in Shaanxi province, and to provide evidences for individualy stratified identification and classification management of obesity metabolic phenotype.

  Methods  Data on 13 072 urban adults aged 20 – 89 years without major diseases were collected from Shaanxi Urban Cohort Baseline Survey of Natural Population Cohort Study in Northwest China conducted from 2017 to 2019. According to the status of obesity and metabolic abnormality, the adults were further divided into four subgroups of metabolic healthy non-obesity (MHNO), metabolic unhealthy non-obesity (MUNO), metabolic healthy obesity (MHO) and metabolic unhealthy obesity (MUO), and the heterogeneity and epidemiological characteristics of different obesity metabolic phenotype groups were analyzed.

  Results  Of all the adults, the majority (66.55%, 8 700) were with MHNO, followed by those with MUNO (22.56%, 2 949), MHO (4.09%, 535) and MUO (6.79%, 888). For the male adults, the proportion of MHNO, MUNO, MHO and MUO population was 55.8%, 27.9%, 6.1% and 10.2%, respectively; the metabolic phenotype of obesity changed with age (χ²_trend = 9.143, P_trend = 0.002), with the proportion of MUNO increasing with the increase of age (χ²_trend = 217.096, P_trend < 0.001) and the proportions of NHNO and MHO decreasing with the increase of age (both P_trend < 0.001). For the female adults, the proportion of MHNO, MUNO, MHO and MUO were 55.8%, 27.9%, 4.09% and 6.79%, and the proportion also changed with age (χ²_trend = 486.235, P_trend < 0.001); the proportion of MUNO, MHO and MUO increased with the increase of age (P_trend < 0.05 all) but the proportion of MHNO decreased with the increase of age (χ²_trend = 738.600, P_trend < 0.001). When the obesity standard changed from body mass index (BMI) ≥ 28.0 to BMI ≥ 25.0, the proportion of MHO increased from 4.09% to 16.06%; when the metabolic abnormality criterion changed from ≥ 2 to ≥ 0, the proportion of MHO decreased from 4.09% to 1.02%.

  Conclusion  The metabolic heterogeneity of obesity exists obviously among urban adults in Shaanxi province; the proportion of the adults with obesity but normal metabolism is low, while the metabolic abnormality is prominent in obese adults.