Thirty years of follow-up data show delayed onset of type 2 diabetes, significant reductions in morbidities and mortality in patients with prediabetes who initiate lifestyle modifications.
Many patients who are diagnosed with type 2 diabetes are usually preceded by a disorder known as impaired glucose tolerance, or pre-diabetes. Impaired glucose tolerance can result from an endogenous disorder in insulin production, secretion, or utilization. After progressing from prediabetes to type 2 diabetes, many secondary vascular complications can develop such as retinopathy, nephropathy, neuropathy, or cardiovascular disease. Patients with prediabetes are usually advised to make diet modifications or initiate exercise before the addition of pharmacotherapy in order to improve their glucose tolerance and prevent type 2 diabetes from manifesting. Through the delay of type 2 diabetes onset in patients with impaired glucose tolerance, it is hypothesized that the risk of developing secondary complications can be reduced as well.
Previous studies have examined the time associated risk of developing secondary diabetic complications. Recently published in the Journal of Diabetes and Its Complications, a study conducted out of Japan found that baseline HbA1c values of 8% or greater resulted in a 33% increased risk of developing secondary retinopathy and a 29% increased risk of developing secondary kidney disease when compared to those patients with an HbA1c within goals of <7%. Baseline HbA1c values were not predictive of increased cardiovascular disease risk. The researchers of this previous study found that incidence of secondary complications were most common within the first 10 years of therapy initiation, which gradually decreased over time.
A more recent study that was presented for the first time at the 79th annual ADA Scientific Sessions conference completed a secondary analysis of the previously published longitudinal Da Qing Diabetes Prevention Study out of China. The original Da Qing study enrolled a total of 576 adults with impaired glucose tolerance who were followed up for 30 years post intervention. Study participants were randomized in a 1:1:1:1 fashion to receive an intervention of diet or exercise or both diet and exercise or control for a total of 6 years. Data showed that an intervention of diet or exercise or both resulted in a 27% risk reduction in the first cardiovascular disease event of any myocardial infarction, congestive heart failure, stroke, or limb amputation (HR 0.73, 95% CI 0.55 – 0.95).
In the most recent publication, patients enrolled in the Da Qing study who completed the entire 30 years of follow up after initial randomization were analyzed to determine long-term health benefits of preventing type 2 diabetes diagnosis with regard to secondary vascular events.
A total of 540 patients out of the original 576 were included in primary analysis due to full completion of the 30 year follow up period post intervention. Results were reported within three cohorts: adults who had developed type 2 diabetes, adults who remained prediabetic, and adults who had improved to normal glucose tolerance, post intervention. Primary outcomes that were observed included composite incidence of microvascular complications and incidence of any cardiovascular disease. Patients part of one of the three intervention groups had a median delay in onset of type 2 diabetes by 4 years. Lifestyle interventions of diet or exercise, or both, provided significant risk reductions for developing cardiovascular diseases (HR 0.74, 95% CI 0.59 – 0.92), microvascular complications (0.65, 0.40 – 0.95), and all-cause mortality (0.74, 0.61 – 0.89).
Results of this new study suggest that early initiation lifestyle modifications can delay the onset of type 2 diabetes and can significantly reduce the risk of developing secondary macro and microvascular complications in patients with impaired glucose tolerance. Providers of patients with prediabetes should consider the results of this newly published study when recommending therapy plans. Educating patients on the results of this study could promote adherence to recommended lifestyle changes if they wish to avoid disease progression and medication initiation.
- Early lifestyle modifications such as diet and exercise can delay the onset of type 2 diabetes in patients with impaired glucose tolerance.
- Intervention with diet and exercise in patients with prediabetes significantly reduced the risk of developing secondary microvascular complications, cardiovascular disease, and all-cause mortality.
- Providers should review the results of this study with patients to promote adherence to lifestyle changes.
References, Delayed Onset of Type 2 Diabetes Through Early Lifestyle Interventions:
- Takao T, Matsuyama Y, Suka M, et al. Analysis of the duration and extent of the legacy effect in patients with type 2 diabetes: A real-world longitudinal study. Journal of Diabetes and It’s Complications 2019; [Epub ahead of print]. DOI: 10.1016/j.jdiacomp.2019.05.005
- Gong Q, Zhang P, Wang J, et al. Morbidity and mortality after lifestyle intervention from people with impaired glucose tolerance: 30-year results of the Da Qing Diabetes Prevention Outcome Study. Lancet Diabetes Endocrinol 2019; 7(6):452-461. DOI: 10.1016/S2213-8587(19)30093-2.
Adam Chalela B.S., PharmD Candidate, USF College of Pharmacy Class of 2020
Reported at the American Diabetes Association 79th Scientific Sessions June, 2019