The Practical Diabetic

Let me cut to the chase on this: if you have been recently diagnosed with diabetes and you maintain good glucose control, based on this evidence, there is NO reason to expect you will not live a long and healthy life

This may sound wrong because it is easy, from a statistical point of view, to work out the difference in life expectancy between people with diabetics and non-diabetics and show people with diabetes live for a few years less than non-diabetics. Sure enough, Mike Stedman and his colleagues did precisely this for EASD 2020.

What this tells us is that Type 1 males live 7 years less than their non-diabetic counterparts and, for women, it is 8.5 years. For Type 2, the difference is less pronounced being 1.4 years lost for men and 2 years lost for women.

The problem is the data, while accurate, is very misleading. Moreover, it hits social media and diabetes groups, and Type 1s think it is inevitable that they will live shorter lives than their friends and families. The stresses of diabetes are plentiful without this kind of burden being added on top.

The fact of the matter is this graph says absolutely nothing about the life expectancy of an individual. Rolled into that average life expectancy are hypo deaths, DKA deaths, and things like heart complications. We know higher HbA1c levels increase the risk of cardiovascular (heart) disease so, for someone with good glucose control, in my opinion, the above graph is meaningless. It also says nothing about age of onset. Someone who was diagnosed 50 years ago (included in the above numbers) had to manage their diabetes with urine, thick needles, and a lot of luck. Someone diagnosed today has much more effective tools at their disposal.

In my opinion, it would be much smarter to look how life expectancy has improved over the years and, where possible, see if it is catching up with the non-diabetic population. This is what I want to write about today. As usual, you can skip to the tl;dr for the summary, otherwise let us go on a journey of optimism, rather than of pessimism. Firstly though, what is up with that gender imbalance in life expectancy?

Why Do Females with Diabetes Have a Shorter Average Life Expectancy?

Again, let me repeat the disclaimer: Average life expectancy says nothing about the life of an individual. A woman with good glucose control has, in my opinion, no reason to expect any shorter life than her non-diabetic peers.

To the question at hand though, another presentation at EASD 2020 looked at this in some detail. Juergen Harreiter presented “What you need to consider for individualised gender-sensitive care”. This looked at the gender differences in diabetes risk and treatments.

Sure enough females with diabetes are at a higher risk of coronary heart disease and stroke than their male counterparts.

and a 40% greater risk of all-cause mortality.

Specific reasons, backed up by data, were light on the ground except for this cited study.

In the above graphs, we have four drugs commonly used to reduce the risk of heart disease. For three of them (statins, RAAS blockades, and beta-blockers) women were routinely under-treated. With males receiving more aggressive treatment, it is not surprising they live longer.

So What About Life Expectancy Improvements over Time?

There is overwhelming evidence that life expectancy is improving every year for people with diabetes. While the cause of the improvement is not always clear, I suspect it has to do with improvements in management technology (insulin improvements, pumping, glucometers, looping etc.) and possibly improved knowledge and education about the disease. Let us go through the papers I have found.

Life expectancy and survival analysis of patients with diabetes compared to the non diabetic population in Bulgaria (2020)

This study looked at data from 2012-2015 using national databases. Even in this short period of time we see improvements across both Type 1 and 2 and across genders.

While the non-diabetic population did not move at all in their life expectancy, Type 1s, Type 2s, Type 1 females, and Type 2 females all gained around an additional year, on average. Moreover, by 2015, the overall life expectancy of people with diabetes was about the same as the non-diabetic population (almost 75 years).

Improvements in the Life Expectancy of Type 1 Diabetes (2012)

In this study the life expectancy of two cohorts was examined: people with diabetes diagnosed between 1950-1964 and between 1965-1980.

Here we see the percentage of survivors after a certain age. The EDC (Pittsburgh Epidemiology of Diabetes Complications) cohort for 1950-1964 are lower on the graph as fewer survived over the years. In comparison, the 1965-1980 cohorts for EDC and ACR (Allegheny County Type 1 Diabetes Registry) had a much higher survival rate again showing the difference just 15 years made in the life expectancy of people with diabetes.

Long-Term Mortality in Nationwide Cohorts of Childhood-Onset Type 1 Diabetes in Japan and Finland (2003)

This study was designed to compare Type 1 diabetics in Japan and Finland but also had information of improved survival rates over the years.

While in Finland, the survival prospects of a Type 1 child remained excellent for the periods 1965-1969 and 1975-1979 with only minor improvements, we see there was a dramatic improvement in survival probability for children diagnosed in the latter period for Japan.

The 30-Year Natural History of Type 1 Diabetes Complications (2006)

This study looked at five 5-year cohorts (1950-1959, 1960-1964, 1965-1969, 1970-1974, and 1975-1980) also from the Pittsburgh Epidemiology of Childhood-Onset Diabetes Complications Study. Not surprisingly, it came to similar conclusions.

We see a clear improvement in survival rates with around 60% of those diagnosed in the 50s and living with the disease for 30 years surviving, compared to around 95% for those diagnosed in the 70s.

All-Cause Mortality Trends in a Large Population-Based Cohort With Long-Standing Childhood-Onset Type 1 Diabetes (2010)

This study split the previously mentioned ACR study into three diagnosis cohorts (1965-1969, 1970-1974, and 1975-1979) to compare survival rates.

As we have seen in the other studies, there was a dramatic improvement in survival rates between someone diagnosed in the late 60s compared to the 70s.

A Word of Warning

In the above studies we have looked at people with diabetes in Bulgaria, USA, Japan, and Finland and, as mentioned, it is likely the improvements are due to improvements in medical technology and education. For countries where these improvements are not available, there is no reason to expect the same gains. For places in the world where insulin is not readily available, there is no reason why life expectancy should be much better for a person with diabetes than it was before the discovery of insulin 100 years ago. These studies show there are compelling reasons for insulin to be available to all who need it, across the world. We are literally robbing people of decades of life if we choose to do nothing.

tl;dr

There is clear evidence that the survival rates for people with diabetes has improved for those diagnosed between 1950 and 2015. Furthermore, in a study from Bulgaria by 2015, the life expectancy of people with diabetes was the same as non-diabetics.

While the specific cause of the improvements was not examined, it is assumed to be a function of improved technology (insulin, pumps, glucometers, looping etc.) and improved understanding and education of the disease.

Therefore, if you have been recently diagnosed with diabetes and you maintain good glucose control, based on this evidence, there is NO reason to expect you will not live a long and healthy life.