Metabolically healthy overweight/obesity with no metabolic abnormalities and incident hyperglycaemia in Chinese adults: analysis of a retrospective cohort study.

OBJECTIVES

To explore whether metabolically healthy overweight (MHOW) and/or metabolically healthy obesity (MHO) increase hyperglycaemia risk in a Chinese population with a broad age range.

DESIGN

Retrospective cohort study.

SETTING

Secondary analysis of data from the DATADRYAD database, comprising health check records of participants from 32 regions and 11 cities in China between 2010 and 2016.

PARTICIPANTS

A total of 47 391 metabolically healthy participants with none of the metabolic abnormalities were selected.

OUTCOME MEASURES

Hyperglycaemia includes incident diabetes and impaired fasting glucose (IFG). Diabetes was diagnosed with fasting blood glucose ≥7.0 mmol/L and typical clinical symptoms and/or on self-report during follow-up. The fasting plasma glucose level of IFG was from 5.6 to 6.9 mmol/L.

RESULTS

With an average follow-up of 3.06 years, 5274 participants (11.13%) developed hyperglycaemia over 144 804 person-years, with an incidence rate of 36.42 per 1000 person-years. Adjusted model revealed a higher risk of incident hyperglycaemia in the MHOW group (HR=1.23, 95% CIs 1.16 to 1.30) and the MHO group (HR=1.49, 95% CI 1.33 to 1.67) compared with the metabolically healthy normal weight group. With 1 unit increase of body mass index, the risk of hyperglycaemia increased by 6% (HR=1.06, 95% CI 1.04 to 1.07). The stratified analyses and interaction tests showed the robustness of the association, and there was a stronger association in women (p for interaction<0.001).

CONCLUSIONS

The MHOW and MHO phenotypes were positively associated with a higher risk of hyperglycaemia in this population, and the association was particularly stronger in women.