Long-term risks for cardiovascular disease and mortality across the glycaemic spectrum in a male-predominant Chinese cohort aged 75 years or older: the Kailuan study

Background: Ageing and diabetes are growing global health burdens. The current understanding of cardiovascular disease (CVD) and mortality risk across the glycaemic spectrum in older populations is limited.

Objectives: This study sought to characterise CVD and all-cause mortality risk across the glycaemic spectrum among Chinese adults aged 75 years or older in a community-based setting over10 years.

Methods: The 3,989 adults in the Kailuan Study were aged over 75 years (median age was 79 years [interquartile range: 76-82]; 2,785 normoglycaemic, 691 prediabetic and 513 diabetic, determined by fasting blood glucose levels) at baseline, predominantly male (92.9% male) and followed until December 2019. Time-varying Cox regression and competing-risk models were used to examine the hazard ratio (HR) of incident CVD and mortality across the glycaemic exposures.

Results: During median follow-up of 11.3 years, 433 first CVD and 2,222 deaths were recorded. Compared with normoglycaemia, multivariable-adjusted models revealed the following: (i) prediabetes was not associated with future risks for CVD (HR: 1.17; 95% CI 0.82-1.69) and all-cause mortality (HR 1.06; 95% CI 0.70-1.60); (ii) diabetes-associated enhanced risks for CVD and all-cause mortality were mainly confined to those exhibiting low-grade inflammation (high-sensitivity C-reactive protein ≥2.0 mg/L) levels. The results were consistent after multiple sensitivity analyses.

Conclusions: Among a male-predominant Chinese population aged 75 years or older, compared with normoglycaemic participants, prediabetes was not associated with an enhanced 10-year CVD and all-cause mortality risk, and diabetes-associated enhanced 10-year risk was mainly confined to individuals exhibiting low-grade inflammation.