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Cardiovascular mortality, all-cause mortality, and diabetes incidence after lifestyle intervention for people with impaired glucose tolerance in the Da Qing Diabetes Prevention Study: a 23-year follow-up study

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Summary

Background

Lifestyle interventions among people with impaired glucose tolerance reduce the incidence of diabetes, but their effect on all-cause and cardiovascular disease mortality is unclear. We assessed the long-term effect of lifestyle intervention on long-term outcomes among adults with impaired glucose tolerance who participated in the Da Qing Diabetes Prevention Study.

Methods

The study was a cluster randomised trial in which 33 clinics in Da Qing, China—serving 577 adults with impaired glucose tolerance—were randomised (1:1:1:1) to a control group or lifestyle intervention groups (diet or exercise or both). Patients were enrolled in 1986 and the intervention phase lasted for 6 years. In 2009, we followed up participants to assess the primary outcomes of cardiovascular mortality, all-cause mortality, and incidence of diabetes in the intention-to-treat population.

Findings

Of the 577 patients, 439 were assigned to the intervention group and 138 were assigned to the control group (one refused baseline examination). 542 (94%) of 576 participants had complete data for mortality and 568 (99%) contributed data to the analysis. 174 participants died during the 23 years of follow-up (121 in the intervention group vs 53 in the control group). Cumulative incidence of cardiovascular disease mortality was 11·9% (95% CI 8·8–15·0) in the intervention group versus 19·6% (12·9–26·3) in the control group (hazard ratio [HR] 0·59, 95% CI 0·36–0·96; p=0·033). All-cause mortality was 28·1% (95% CI 23·9–32·4) versus 38·4% (30·3–46·5; HR 0·71, 95% CI 0·51–0·99; p=0·049). Incidence of diabetes was 72·6% (68·4–76·8) versus 89·9% (84·9–94·9; HR 0·55, 95% CI 0·40–0·76; p=0·001).

Interpretation

A 6-year lifestyle intervention programme for Chinese people with impaired glucose tolerance can reduce incidence of cardiovascular and all-cause mortality and diabetes. These findings emphasise the long-term clinical benefits of lifestyle intervention for patients with impaired glucose tolerance and provide further justification for adoption of lifestyle interventions as public health measures to control the consequences of diabetes.

Funding

Centers for Disease Control and Prevention, WHO, the China-Japan Friendship Hospital, Da Qing First Hospital.

Introduction

Lifestyle interventions for people with impaired glucose tolerance can delay or prevent the development of diabetes and lead to improvements for other cardiovascular risk factors.1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 However, whether these changes reduce the incidence of long-term complications, and the excess cardiovascular disease and all-cause mortality that accompany diabetes is uncertain.12, 13 In our previous analysis7 of 20-year follow-up data from the Da Qing Diabetes Prevention Study, we reported a statistically insignificant 17% reduction in cardiovascular disease mortality and a significantly lower incidence of severe diabetic retinopathy that seems to have been mediated primarily by delaying the onset of diabetes.14 Because cardiovascular disease is the major cause of excess mortality in people with impaired glucose tolerance, more definitive information about the effect of lifestyle intervention on cardiovascular disease and all-cause mortality in such people has crucial public health implications. We assessed such effects in people who participated in the Da Qing Diabetes Prevention Study over a 23-year period.

Section snippets

Study design and participants

The design of the Da Qing Diabetes Prevention Study and the 20-year follow-up study have been reported previously.1, 7, 14 In 1986, 33 primary care clinics in Da Qing, China serving 577 people with impaired glucose tolerance were enrolled into a cluster randomised trial. All patients treated at the clinics were eligible if they had impaired glucose tolerance in 1985. We did a 20-year follow-up study up to the end of 20067 and here report results after an additional 3 years. The institutional

Results

Of the original 577 study participants, one declined the baseline examination, eight had only a baseline examination, and 20 participants were lost to follow-up during the 6-year intervention period, mainly because of job relocation. During the subsequent 17 years after the intervention, only six participants were lost to follow-up. Thus, 542 participants (94%) had complete data for mortality and 568 (99%) contributed data to the analysis (figure 1). 563 participants (98%) had complete data for

Discussion

This study is the first randomised clinical trial to show that lifestyle intervention in people with impaired glucose tolerance reduces all-cause and cardiovascular disease mortality (panel). These findings seem to mainly be a result of lower mortality among women in the intervention group. The Malmo study13 showed lower mortality over a 12-year period in men with impaired glucose tolerance treated with lifestyle intervention compared with a group who received routine treatment, but the study

References (33)

  • TJ Orchard et al.

    Long-term effects of the Diabetes Prevention Program interventions on cardiovascular risk factors: a report from the DPP Outcomes Study

    Diabet Med

    (2013)
  • J Lindstrom et al.

    Improved lifestyle and decreased diabetes risk over 13 years: long-term follow-up of the randomised Finnish Diabetes Prevention Study (DPS)

    Diabetologia

    (2013)
  • M Uusitupa et al.

    Ten-year mortality and cardiovascular morbidity in the Finnish Diabetes Prevention Study–secondary analysis of the randomized trial

    PLoS One

    (2009)
  • KF Eriksson et al.

    No excess 12-year mortality in men with impaired glucose tolerance who participated in the Malmo Preventive Trial with diet and exercise

    Diabetologia

    (1998)
  • Q Gong et al.

    Long-term effects of a randomised trial of a 6-year lifestyle intervention in impaired glucose tolerance on diabetes-related microvascular complications: the China Da Qing Diabetes Prevention Outcome Study

    Diabetologia

    (2011)
  • Diabetes Mellitus. Report of a WHO Study Group. 727, 1–113

    (1985)
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