Independent and combined associations of abdominal obesity and seated resting heart rate with type 2 diabetes among older Chinese: the Guangzhou Biobank Cohort Study

BACKGROUND: Central obesity and poor physical fitness predict the development of type 2 diabetes and cardiovascular mortality among Caucasian populations. We studied the independent and combined effect of abdominal obesity and seated resting heart rate used as an indicator of physical fitness, on the presence of type 2 diabetes among 30 519 older residents of Guangzhou, Southern China. METHODS: Participants were stratified into four groups, based on the Asian criteria for abdominal obesity (≥90/≥ 80 cm in men/women) and the 75% cut-off point for seated resting heart rate (≥83 beats per min). The association with type 2 diabetes was assessed using multivariable logistic regression. RESULTS: A total of 3777 (12.7%) volunteers were diagnosed with type 2 diabetes, which was independently associated with seated resting heart rate and, in particular, increasing levels of abdominal obesity (p < 0.001). An odds ratio of 3.93 (95% confidence interval = 3.48-4.43) was identified for type 2 diabetes in participants who were obese with a seated resting heart rate ≥ 83 beats per min after adjusting for potential confounders. CONCLUSIONS: Higher seated resting heart rate, a marker of poor physical fitness, independently doubles the risk of type 2 diabetes. The strength of this association is further increased when abdominal obesity is considered.