In this study, 305 participants with more than 50 years of type 1 diabetes answered questions about insulin pump therapy via a questionnaire. We first found that 44% of participants were using an insulin pump vs. 56% using multiple daily insulin injections. Average blood sugar control was about the same in both subgroups (HbA1c 7.4% non-pump vs. 7.6% pump). The pump subgroup reported a greater number of minor low blood sugar events in the last year, but fewer severe low blood sugar events (those needing help from another person to correct). In the overall research group, the use of a continuous glucose monitoring for one week or more per month was also associated with a lower risk of severe low blood sugar events. The only diabetes self-management skill that was found to be associated with better blood sugar control in the group was more frequent daily glucose tests. In conclusion, basic self-management skill and technology play complementary roles in glycemic control among older adults with long-standing type 1 diabetes – success isn’t simply because someone uses an insulin pump or not, but how they approach their therapy.
People who live with both longstanding type 1 diabetes and neuropathy may also experience poor mental health outcomes. In this study, participants who had lived with type 1 diabetes for more than 50 years completed a questionnaire to assess depression and emotional distress. They also reported their history of neuropathy complications, including symptoms such as pain, numbness and tingling, or leg/foot involvement. Overall, our team found low rates of distress (5.9%) and depression (10.9% mild, 3.4% severe) in this remarkably resilient population. However, we did find that participants with diabetic neuropathy had a higher chance of experiencing depression and emotional distress. While some have previously attributed this to the pain that can come with neuropathy, this study found that neuropathy - even without pain - was associated with these negative psychological outcomes. We believe this may be due to a combination of things, including limitations to physical and social activity, unsteadiness, and limited treatment options. These results lead us to believe that older individuals with diabetic neuropathy may benefit from mental health screening and other interventions.
Diabetic Retinopathy (diabetic eye disease) is the most common cause of preventable blindness in adults, and the most common vascular complication in people with diabetes. Researchers know that high blood sugar levels can damage the eyes through a system called renin-angiotensin aldosterone system (RAAS). While there are treatments to block RAAS, this study wanted to understand if RAAS is still active in the eye after patients develop diabetic eye disease, and after many years with type 1 diabetes. We also wanted to know if RAAS causes damage in other parts of the body. Our team looked at participants from the Canadian Study of Longevity in Type 1 Diabetes, who had all lived with T1D for more than 50 years. They found that those people with the most advanced eye disease had the highest levels of RAAS activity. Patients with high RAAS activity also had more stiffening of the arteries behind the eye. Those in the study with persistent diabetic retinopathy also had worse nerve function and higher risk for plaque buildup in the arteries. Though the ultimate goal is to prevent eye injury altogether in people with type 1 diabetes, this knowledge is helpful because it shows that the use of RAAS blocking drugs in people with long-standing T1D may be beneficial and opens up the opportunity to study other areas of connection between RAAS and the body.
Diabetic kidney disease (DKD) is a serious complication of type 1 diabetes. Our study aimed to explore clinical and biochemical factors, including the achievement of American Diabetes Association (ADA) recommended targets associated with DKD in people living with type 1 diabetes for more than 50 years. The study found that meeting the ADA recommended clinical targets (such as for blood sugar, blood pressure, cholesterol) was associated with better estimated glomerular filtration rate and lower prevalence of diabetic retinopathy. In adults with prolonged T1D duration, older age at diagnosis and lower heart rate variability may be associated with DKD. Vascular complications are increasingly common after prolonged T1D disease duration, though some people, for reasons that are not clear, are resistant to the development of such chronic complications even when they appear not to have met the protective clinical targets.
Longstanding diabetes can affect bone health. We are not entirely sure why this happens, although it is likely linked to high blood sugar. To better understand the relationship, our research team studied the effect of having longstanding diabetes on bone mineral density and the risk of fractures using a whole body bone scan and a questionnaire that determined if participants had experienced any fractures. All of the data collected from the participants with type 1 diabetes were compared to participants of similar age and sex without diabetes.
The study found that females with type 1 diabetes, on average, had a higher bone density at the lumbar compared to females without diabetes, but no difference at any other measurement site. Males with diabetes did not have different bone mineral density compared to males without diabetes. Despite this higher bone mineral density, people with longstanding type 1 diabetes were more likely to have experienced a fragility fracture. This work shows us that standard bone mineral density measures may not predict risk in people with type 1 diabetes as it does in people without diabetes. With these results, we hope that the research community will appreciate the need to find better measures of bone fracture risk in people with type 1 diabetes.
Participants in the Canadian Study of Longevity in Type 1 Diabetes are similar to Americans included in the Joslin Medalist Cohort: both studied individuals who have had type 1 diabetes for more than 50 years, and collected information using similar surveys and questionnaires. This study compared Canadian and American participants in order to determine if differences in health care systems or access to health care affect diabetes outcomes. We found that diabetes complication rates were similar between Canadians and Americans but Canadians had higher HbA1c (7.5% for Canadians versus 7.2% for Americans), less insulin pump use (43% of Canadians versus 56% of Americans), and reported lower quality of life. However, Canadians seemed to have fewer heart attacks and strokes, likely related to better uptake of proven heart-protective medications (“statins”). These results require confirmation in the broader type 1 diabetes population in Canada and if confirmed, require strategies to improve diabetes management in Canada. Though we cannot be certain about these results, they do suggest that differences in health care systems and clinical practice guidelines do indeed have an impact on the lives of people with diabetes.
Previous studies have shown that people with type 1 diabetes are at greater risk for autoimmune disorders, such as thyroid disease, Graves’ disease, rheumatic arthritis, celiac disease, and others. This study aimed to determine how prevalent autoimmune diseases were in those who had lived with type 1 diabetes for more than 50 years, to learn whether there were differences in prevalence for men and women, and to evaluate whether having an autoimmune disorder would increase the likelihood of developing other complications, such as heart disease, nerve damage or kidney disease. Those with 50 years or more of type 1 diabetes are an important group to study because they are most likely to have already shown their lifetime risk of developing another autoimmune disease, unlike those who have had a shorter duration of diabetes.
By studying the data we had collected from the Canadian Study of Longevity in Adults with Type 1 Diabetes, we determined that the estimated risk of autoimmune disease in someone who had lived with diabetes form more than 50 years was 49.3%. Women were at greater risk, as they are more prone to developing thyroid disease. Those with a non-thyroid autoimmune disease had a lower likelihood of developing heart complications, and women had a higher likelihood of developing kidney-related complications. While further study is needed, this information shows that physicians should consider the increased likelihood of an autoimmune disease when treating those with type 1 diabetes.”
There is an urgent need to better identify the presence of early-stage diabetic neuropathy (nerve damage), as this is the time when therapy is most likely to be effective. Corneal confocal microscopy has emerged as a potential way to identify early neuropathy by looking at the small nerve fibers in the cornea. This tool has been shown to work in studies of younger adults with type 1 diabetes and this study confirmed that it can also work identifying diabetic neuropathy in older adults with longstanding diabetes. It is our hope that such a simple tool, which could be used by eye specialists, could one day be used during the routine yearly eye examination for those with diabetes. In this way, people could be screened for both eye and nerve disease at the same time.
Diabetic neuropathy is a common diabetes complication that can involve pain, numbness, tingling and weakness beginning in the feet and then moving beyond. This study was done to prove the results from the Phase 1 study, which was based on a questionnaire. The first study results showed females experience greater pain from neuropathy than men. This new study involved doing specialized physical tests (nerve conduction tests) to confirm these results in 75 patients who have had type 1 diabetes for more than 50 years. It found that neuropathy tended to be more common in males (97% compared to 83%), but this difference was not statistically significant. Despite better neuropathy treatment measures in females compared to males, there was a trend towards higher neuropathic pain in females (29% vs 21%). More study will be needed to understand the significance of this difference, but it implies that women may struggle more with troublesome neuropathy symptoms even if neuropathy is technically more common in men. While the ultimate goal is to find ways to help treat the painful symptoms of neuropathy, these results are important in that they highlight for the research community that this may be more complicated to achieve in women with neuropathy.
Central adiposity, or weight carried around the belly/lower torso area, is an important risk factor for heart and kidney disease in those with and without type 1 diabetes. This study looked at the relationship between weight carried in the lower torso area and blood flow in the kidney in adults with long-standing type 1 diabetes. Our team found that weight carried in this area has an impact on kidney function in this population. While there was also a relationship between weight in the lower torso and blood flow in the kidney in those with type 1 diabetes and diabetic kidney disease, there was some variation in the results in this population that requires further study. While this study does not provide a direct answer for preventing kidney disease in those with type 1 diabetes, it does help to highlight a potential role of overweight and obesity in harming kidneys.
Those with longstanding type 1 diabetes have a much greater risk of major heart and vascular disease. An important way to lower this risk is by taking statin medications, which decrease "bad cholesterol" (called LDL - low-density lipoprotein). While some patients may only take statins if they have had previous cardiovascular disease (secondary prevention), clinical guidelines recommend that all older patients with longstanding diabetes should be on statins, even if they have not had previous heart disease (primary prevention). This study aimed to determine whether these guidelines are being followed in Canadians with over 50 years of longstanding type 1 diabetes. We found that the rate of statin use was much lower in primary prevention (65.5%) than in secondary prevention (84.8%), though both subgroups showed adherence to other recommendations such as not smoking, engaging in physical activity, and eating a proper diet. Clinicians and patients should be aware that a lot of people with type 1 diabetes who are at very high risk for heart attacks and strokes still do not take statin pills – This is a major missed opportunity, as statins are a well-proven class of medications for prevention of heart attacks and strokes.
Heart disease is a serious complication in type 1 diabetes, and remains the leading cause of premature death. Interestingly, many patients who develop heart disease (atherosclerosis or hardening of the arteries) also develop damage in other organs including the eyes, nerves, kidney – these are called microvascular complications. In the longevity study we looked at how the development of atherosclerosis is linked to the development of damage in microvascular organs. Looking at calcium deposits in the heart to measure atherosclerosis, we found those that had more atherosclerosis were also the ones who had the highest rates of damage in the microvascular organs - nerves and eyes. We think this information will be used for further study into better understanding pathways that link both the heart, nerves, and eyes so that we can develop new ways to prevent damage to all organs in patients with type 1 diabetes.
Kidney disease is a common and potentially fatal complication of type 1 diabetes, especially when it is paired with premature heart disease. Fortunately, not all people with longstanding type 1 diabetes will develop this complication. Being able to identify factors that are different between those who get diabetic kidney disease and those that don’t might be helpful in preventing the disease. This study identified key elements of kidney function that were different between those with diabetic kidney disease and those who didn’t develop it. In particular, we found that there were significant differences in a hormonal pathway known as the renin-angiotensin system (RAAS). This is a system in our bodies that regulates blood pressure and kidney function. The research team found that this system impacts the blood vessels coming into the kidney (as opposed to the blood vessels leaving the kidney) in people with type 1 diabetes with kidney disease compared, to those that do not develop this condition. This was a critically important finding because the current kidney protective therapies (medications that block the RAAS System) work primarily on the blood vessels leaving the kidney, meaning that we may in future have the capacity to affect the blood vessels that come into the kidney such as to develop new drugs aimed at these vessels to maximally prevent kidney disease. The ultimate goal is to find new therapies that protect kidneys from injury, and this study directs the research community to focus on the "afferent arterioles" - the blood vessels coming into the kidney - as a new, previously unknown, target for promising new therapies
Uric acid is a normal component of urine. When there is a high concentration of uric acid in the blood it increases the risk of developing kidney disease. This study looked at the relationship between normal plasma uric acid (PUA) levels and kidney function in adolescents, young adults and older adults with type 1 diabetes. This allowed us to look at the role of uric acid over the lifetime of type 1 diabetes. They found that only older adults with type 1 diabetes and higher PUA had increased arterial stiffness and renin angiotensin aldosterone system (RAAS). This means that longstanding type 1 diabetes duration may change the association between PUA and kidney functioning. This raised the possibility that lowering uric acid might be an additional layer of protection. This work and prior work justified a large-scale clinical trial, called the “PERL Study” which tested this hypothesis. More work must be done to see if using medications to lower PUA levels will prevent or reverse kidney damage in those with longstanding type 1 diabetes. However, this study strongly suggested that lowering uric acid may be one of the ways to help normalize “afferent arterioles”, the new target identified by the prior study as an area to focus on for kidney health.