Aim
We aimed to investigate the long‐term influence of a diet and/or exercise intervention on long‐term mortality and cardiovascular disease (CVD) events.
Methods
The Da Qing Diabetes Prevention Study had 576 participants with impaired glucose tolerance (IGT) randomized to diet‐only, exercise‐only and diet‐plus‐exercise intervention group and control group. The participants underwent lifestyle interventions for 6 years. The subsequent Da Qing Diabetes Prevention Outcome Study was a prospective cohort study to follow‐up the participants for up to 24 years after the end of 6‐year intervention. In total, 540 participants completed the follow‐up, while 36 subjects lost in follow‐up. Cox proportional hazards analysis was applied to assess the influence of lifestyle interventions on targeted outcomes.
Results
Compared with controls, the diet‐only intervention in people with IGT was significantly associated with a reduced risk of all‐cause death [hazard ratio (HR) 0.77, 95% confidence interval (CI) (0.61‐0.97)], CVD death [HR 0.67, 95% CI (0.46‐0.97)] and CVD events [HR 0.72, 95% CI (0.54‐0.96)]. The diet‐plus‐exercise intervention was significantly associated with a decreased risk of all‐cause death [HR 0.64, 95% CI (0.48‐0.84)], CVD death [HR 0.54, 95% CI (0.30‐0.97)] and CVD events [HR 0.68, 95% CI (0.52‐0.90)]. Unexpectedly, the exercise‐only intervention was not significantly associated with the reduction of any of these outcomes, although there was a consistent trend towards reduction.
Conclusions
A diet‐only intervention and a diet‐plus‐exercise intervention in people with IGT were significantly associated with a reduced risk of all‐cause death, CVD death and CVD events, while an exercise‐only intervention was not. It suggests that diet‐related interventions may have a potentially more reliable influence on long‐term vascular complications and mortality.