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type 1 or type 2?

I

iris peleg

Member
Let's think of the following situation:
I was diagnosed as diabetic. I am over 30 years old. Not fat, exercise from time to time and no diabetes history in my family. How does the doctor decide if I am type 1 or type 2?

The lab test c-peptide can distinguish between the two.

C-peptide test
Definition:
In biochemistry, peptide is a compound of two or more amino acids.

What is c-peptide?
The pancreas secretes proinsulin, comprised of insulin and c-peptide molecules bound together. The two types of molecules split and are released into the bloodstream. The insulin is the active hormone, while c-peptide remains biologically inactive. Consequently, it is possible to measure the level of c-peptide in the bloodstream which would indicate the amount of insulin secreted by the pancreas. It is for this reason that the injected insulin does not affect the c-peptide level.

Type 1 diabetes: The c-peptide level is extremely low, since the pancreas nearly ceases the production of insulin. During the honeymoon period, the pancreas still secretes low amounts of insulin, resulting in low c-peptide level.
Type 2 diabetes: The pancreas is still active and secretes insulin. Due to insulin resistance, the cells do not respond properly to insulin, prompting the pancreas to increase its production. Consequently, the c-peptide level would be either normal or above the average.


Iris peleg
 
In the scenario you give C- peptide is a useful, indication and I'm very sure many more people should be tested than are, but it's not the whole picture, which would include history, family history, autoimmnune tests, insulin sensitivity etc any good specialist will look at all of that, not just one test.
Undiagnosed, but nevertheless longterm type 2s mayhave very low levels of c peptide(and be very thin), people with LADA((a subtype of type 1) may have low normal levels that decrease over some years, people with MODY also have normal or near normal levels, surprisingly many long term type 1s (50 year Joslin medallists) still have recordable c-peptide
 
T2s typically have high insulin production, combined with insulin resistance.
In general in this country, T1 or T2 is determined by guess work and/or etiology.
If you are out of your teens, you must be T2 :mrgreen:
Otherwise, T1 tends to come on fast, with significant weightt loss, severe thirst etc.
T2 creeps up . Often in the over 40s.
Still the ildest new T1 is reputed to have been 93
Hana
Fortunately, It's the effectiveness of the treament, which matters more than the diagnosis.
 
hanadr said:
Otherwise, T1 tends to come on fast, with significant weightt loss, severe thirst etc.
T2 creeps up . Often in the over 40s.
Click to expand...

Yeah, I was thinking along those lines. I was 30 when I was diagosed with T1 and it came on me very quickly. Started with just one day when I just felt quite sick. Next day I felt fine but within a week I noticed I was losing weight (and I was a skinny minnie to start with and couldn't afford to lose any lbs). Then about a week later my vision got quite bad, very blurry. These were symptoms strongly associated with T1.

The hospital did do a test and it was confirmed as T1. TBH,
 
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