Much of the research on length of life for individuals living with type 1 diabetes is pessimist, which makes a new study released recently a breath of fresh air. Data were collected for the ongoing nationwide, multicenter, Finnish Diabetic Nephropathy (FinnDiane) Study that tracked the death rate of 2,639 study participants for an average of 11.4 ± 3.5 years (1).
In this study, participants’ leisure time physical activity was reported via a self-report questionnaire. Importantly, their physical activity and its intensity, duration, and frequency were examined related to dying from all causes and from cardiovascular events; some of these adults with type 1 diabetes already had diabetic kidney disease.
The researchers also looked at potentially confounding factors like sex, how long people had been diagnosed with type 1 diabetes and how old they were when they got it, as well as physical measures like their systolic blood pressure, triglycerides (blood fats), BMI (body mass index), and HbA1c (a measure of overall blood glucose control over two to three months).
The conclusions of this study came as no surprise to me: exercise is associated with a lower risk of premature death from cardiovascular or any other cause in adults with type 1 diabetes. Overall, 270 people died during the follow-up period, 127 of whom had kidney disease. Only exercise intensity was associated with cardiovascular mortality, with intense activity being best for preventing early death from cardiovascular events. Both how much total physical activity they got and how frequently they exercised were associated with a lower risk of dying from any cause.
Prior studies have shown that exercise frequency may also matter in preventing such events, with a higher frequency of physical activity lowering the risk (2). People with type 2 diabetes have already been shown to have a lower risk of premature death when they are physically active (3); this is also true for the adult population in general (4; 5). However, not as many studies have looked specifically at the association between physical activity and lower mortality risk in adults with type 1 diabetes.
Type 1 diabetes has previously been associated with a shorter lifespan in many adults with it, particularly related to endothelial dysfunction and cardiovascular disease (6). Earlier studies, such as the DCCT, have shown that keeping blood glucose levels in a more normal range can help lower the risk of diabetes-related complications in people with type 1 diabetes. Most deaths in this population are related to either cardiovascular events or kidney failure. Exercise has an innate ability to lower oxidative stress, which has been implicated in the development of many complications, as well as improve endothelial function (6).
While regular physical activity is associated with a lower risk of early death in adults with and without type 2 diabetes, this study is one of the first to examine this association in type 1 diabetes. While the exact amount of exercise needed to lower the risk of cardiovascular events is unknown and not determined by this study, doing any activity is arguably better than remaining sedentary. As in people without diabetes, intense activity likely is even more cardioprotective than moderate or light activity.
However, the exercise in this study was self-reported and only collected at the start of the study, making it is hard to draw definitive conclusions about how much exercise people need to do and how intense it needs to be to reduce the risk of dying.
In conclusion, as confirmed by this latest study, being physically active on a regular basis is critical to living long and well with type 1 diabetes. Remaining sedentary is far worse for your health and your longevity, so go get active!
References cited:
1. Tikkanen-Dolenc H, Waden J, Forsblom C, Harjutsalo V, Thorn LM, Saraheimo M, Elonen N, Tikkanen HO, Groop PH: Physical Activity Reduces Risk of Premature Mortality in Patients With Type 1 Diabetes With and Without Kidney Disease. Diabetes Care 2017;16:dc17-0615
2. Tikkanen-Dolenc H, Waden J, Forsblom C, Harjutsalo V, Thorn LM, Saraheimo M, Elonen N, Rosengard-Barlund M, Gordin D, Tikkanen HO, Groop PH: Frequent and intensive physical activity reduces risk of cardiovascular events in type 1 diabetes. Diabetologia 2017;60:574-580. doi: 510.1007/s00125-00016-04189-00128. Epub 02016 Dec 00124.
3. Loprinzi PD, Sng E: The effects of objectively measured sedentary behavior on all-cause mortality in a national sample of adults with diabetes. Prev Med 2016;86:55-57
4. Biswas A, Oh PI, Faulkner GE, Bajaj RR, Silver MA, Mitchell MS, Alter DA: Sedentary time and its association with risk for disease incidence, mortality, and hospitalization in adults: a systematic review and meta-analysis. Ann Intern Med 2015;162:123-132
5. Chau JY, Grunseit AC, Chey T, Stamatakis E, Brown WJ, Matthews CE, Bauman AE, van der Ploeg HP: Daily sitting time and all-cause mortality: a meta-analysis. PLoS One 2013;8:e80000
6. Bertoluci MC, Ce GV, da Silva AM, Wainstein MV, Boff W, Punales M: Endothelial dysfunction as a predictor of cardiovascular disease in type 1 diabetes. World J Diabetes 2015;6:679-692