Intensive treatment for type 1 diabetes is associated with lower risk of deathBMJ 2015; 350 doi: https://doi.org/10.1136/bmj.h32 (Published 07 January 2015) Cite this as: BMJ 2015;350:h32
Initial intensive treatment for type 1 diabetes is associated with a modestly lower all cause mortality rate than conventional therapy, research published in JAMA has shown.
Researchers carried out a long term follow-up study of participants in the original Diabetes Control and Complications Trial, which included 1441 patients with type 1 diabetes who were aged 13 to 39.1 Of these people, 711 were assigned to receive intensive therapy that aimed to get blood sugar control as close to the non-diabetic range as was safely possible, and 730 were assigned to conventional therapy with the goal of avoiding symptomatic hypoglycaemia and hyperglycaemia. At the end of the initial trial after an average of 6.5 years, intensive therapy was taught and recommended to all participants.
The same cohort was then followed for an average of 27 years. During the study 107 deaths occurred—64 in the conventional group and 43 in the intensive group. The overall mortality risk in the intensive treatment group was lower than in the conventional treatment group (hazard ratio 0.67 (95% confidence interval 0.46 to 0.99); P=0.045), although the absolute risk reduction was small at about 1/1000 patient years. The most common causes of death were cardiovascular events (22%), cancer (20%), acute diabetes complications (18%), and accidents or suicide (17%).
Intensive diabetes therapy is now the recommended standard of care, after research showed that it reduced renal and cardiovascular disease, the main causes of early mortality. However, it has not been established whether mortality in type 1 diabetes is affected after intensive glycaemic therapy. In type 2 diabetes, reducing glycaemia to nearer the non-diabetic range has not consistently reduced mortality.
Many patients find it difficult to sustain intensive therapy, as shown by a rise in mean HbA1c levels after completion of the original trial. After five years HbA1c levels were not significantly different between the two groups.
The authors wrote that intensive therapy is also associated with increased hypoglycaemic risk, which in turn has been associated with increased mortality. But they concluded, “These results provide reassurance that adoption of 6.5 years of intensive therapy in type 1 diabetes does not incur increased risk of overall mortality.”
Cite this as: BMJ 2015;350:h32