Thread by @GidMK

Today is #WorldDiabetesDay so let's talk diabetes epidemiology

Basically, that means who gets diabetes, what happens to them, and what we can do to prevent it

It's a scary topic 1/

Firstly - what is diabetes?

The WHO defines it as: "A chronic disease that occurs either when the pancreas does not produce enough insulin or when the body cannot effectively use the insulin it produces" 2/

There are three main types of diabetes: type 1, type 2, and gestational

Type 1 is an autoimmune condition that has genetic and epigenetic roots

Type 2 is a developed condition that is due to insulin resistance

Gestational is high blood sugar occurring due to/in pregnancy 3/

Generally, we split diabetes up into type 1/2 and gestational, because they are different in many ways

In particular, gestational diabetes is usually transitory, although it may predispose women to type 2 diabetes later in life 4/

When we are talking about diabetes epidemiology - looking at diabetes on a population scale - we are also mostly talking about type 2 diabetes

That's because of the type 1/2 split 5/

Of the people diagnosed with diabetes, about 90% will have type 2 diabetes, with 10% having type 1 6/

This is important because type 2 diabetes is partially preventable, while type 1 is not 7/

Which brings us to the scary part

You see, diabetes rates are increasing 8/

In Australia - where I live - we've gone from an estimated national diabetes rate of ~2% in 1992 to ~6% today in 2018 9/

But this data is problematic: it's either based on self-report (scientists asking people if they have diabetes) or people enrolled in diabetes services 10/

The issue here is that only people who are diagnosed will self-report, or access services

But you can live with type 2 diabetes for years without having any outward signs

What about undiagnosed people? 11/

We aren't entirely sure how many people are living with diabetes without a diagnosis, but recent research has put the figure at 25-50% 12/

So when we look at our diabetes estimates, we have to add at least 25%, and maybe as much as 50%, on!

That means the diabetes prevalence in Australia is probably 8-10%, maybe more 13/

Diabetes is also an unequal issue

What do I mean by that?

Well, people who are disadvantaged - economically, socially, etc - are much more likely to develop type 2 diabetes 14/

Poor, rural areas have diabetes rates up to five times (!) higher than wealthy, urban places

This gets even worse when we look at ethnicity and other cultural barriers 15/

In Australia, Indigenous and Torres Strait Islander peoples see rates of DIAGNOSED diabetes as high as 13%

If you include the undiagnosed population, we're looking at somewhere between 17-21%

This is a major failing of the health system and society 16/

My team has looked at diabetes rates by mapping them across Sydney, and it's fairly easy to see the societal split

Red means more diabetes. You can see a pretty clear divide between the wealthier east and more disadvantaged western suburbs 17/

This burden of diabetes is a big issue. Diabetes is one of the leading risk factors for ill health globally

It causes damage to eyes, kidneys, hearts, and more 18/

It's also very EXPENSIVE. The cost of diabetes to our health system is skyrocketing 19/

These increases in diabetes are largely driven by increases in type 2 diabetes

Type 2 diabetes is largely driven by increases in weight

This brings us back to the "preventable" aspect 20/

We estimate that if we could drop the average weight by about 4kg, we would see dramatic reductions in the rate of diabetes 21/

This is particularly hard, given the social disadvantage angle

It is MUCH easier for people who are wealthy, and can access services, to lose weight (this is what my PhD is on) 22/

It's important to remember that social disadvantage affects all areas of the healthcare system

For example, some of our research has shown that people who speak a language other than English have much worse outcomes when they are admitted to hospital for diabetes 23/

There's also another growing issue

So far I've mostly been talking about type 2 diabetes, but what about gestational? 24/

Research from some of my colleagues has shown that the rate of gestational diabetes has more than doubled in the last decade in western Sydney

This is truly terrifying 25/

(FYI, that graph technically shows total number of GDM pregnancies, but the number of pregnant women has only grown by about 20% since 2002 so it represents a >2x increase in the rate) 26/

Remember: gestational diabetes may be transitory (by definition), but the effects are not

Women with gestational diabetes are more likely to develop type 2 diabetes. The same is true of their children

This makes the problem intergenerational 27/

Even if we intervene today, reduce everyone's weight by 4kg in the next year, we'll still likely see diabetes rates continue to climb for some time yet 28/

But, there is hope!

At the individual level, there are numerous ways to prevent, and even reverse, diabetes 29/

We've now seen several trials show that, if you have type 2 diabetes, you can reverse the disease and go into 'remission' by losing 8-15kg of weight 30/

Similarly, if you have pre-diabetes - an intermediate stage where between normal blood sugar and diabetes - you can reduce your risk of getting diabetes significantly with just a few kilos of weight-loss 31/

From a population perspective, there are proven effective interventions focused on providing a health environment that can reduce the risk of diabetes for everyone 32/

These include things like a sugar tax, improved active transport (like cycling!), reducing barriers to healthy eating, and more 33/

Ultimately, a strategy focused on the individual AND society is vital to reverse the trend in diabetes that we are seeing emerge 34/

What can you do?

1. Advocate for change
2. Find local groups and work with/support them
3. Talk to healthcare providers about setting personal goals
4. ADVOCATE FOR CHANGE 35/

Our diabetes problem has been 30 years in the making

It will not be solved overnight

But the only way we can make a dent is if everyone - from you to the politicians who represent you - cares enough to do things differently 36/

Some useful resources #WorldDiabetesDay

WHO - who.int/news-room/fact…
Diabetes Australia - diabetesaustralia.com.au
Western Sydney Diabetes - westernsydneydiabetes.com.au
AIHW Report - aihw.gov.au/reports/diabet…
Global Estimate of Diabetes - ncbi.nlm.nih.gov/pubmed/24300018

Oh also - if you think you might be at risk of diabetes, or are worried about anything you read here, have a chat with your GP

You might need a test, you might not, but your doctor is the best place to go!