CDT and Percentages- Please explain!

[DesignerGirl]

I understand about CDT percentages required to pass the medical blood tests. How are these worked out? For instance, if you had recently been to the doctor and told your reading was double what it should be does that make it 2%? Also, if you had halved your drinking but not actually abstained would that reduce your CDT readings by 50 per cent? I Thanks for any advice.

 

[white43]

I understand about CDT percentages required to pass the medical blood tests. How are these worked out? For instance, if you had recently been to the doctor and told your reading was double what it should be does that make it 2%? Also, if you had halved your drinking but not actually abstained would that reduce your CDT readings by 50 per cent? I Thanks for any advice.

CDT measures the amount of deficient transferrin in your blood. Alcohol depletes the transferrin of carbohydrate, so the more you drink, the heavier the drinking, the longer the duration - the higher this will make the percentage.

A normal reading of CDT would probably be 1% or lower.

It is theorised that sustained drinking over a two week period of say a bottle of wine a day could push up your CDT level to 3%.

Without knowing what your GP determines as 'normal', it's difficult to say what they deem as 'double' what it should be.

Also - without knowing what you are drinking and with what regularity, it's impossible to say that your CDT levels will come down, it doesn't take much to push it up, as above. The only sure way to bring CDT down is to abstain from drinking for at least two weeks. This should half your current CDT level.

If you are approaching a DVLA medical, you really should abstain and not play CDT-roulette. Recent readings suggest 4 weeks of abstinence will bring your CDT levels down to passable levels.

 

[DesignerGirl]

Thanks for the reply, well I 'half' abstained so it is in the lap of the Gods now, the medical went well but it is all down to the blood test now! All I know is a 'normal' figure is 50 or under and I was 100 back in February. I took the latest last possible medical appointment so it was either lose all my money applying for the licence or give it a shot! Fingers crossed, wait and see!

 

[white43]

Thanks for the reply, well I 'half' abstained so it is in the lap of the Gods now, the medical went well but it is all down to the blood test now! All I know is a 'normal' figure is 50 or under and I was 100 back in February. I took the latest last possible medical appointment so it was either lose all my money applying for the licence or give it a shot! Fingers crossed, wait and see!

CDT is not measured that way(50/100). It could be your GP was giving you Liver Function Test results - which aren't measured anymore for DVLA purposes. A lot of GP's don't seem to be clued in to the CDT test.

If you look at my other thread, you can contact DVLA and get results of your blood test.

 

[DesignerGirl]

Thanks, it was definitely regarding alchohol levels, I had full blood tests at the hospital and saw a consultant in February. He asked when I last had a drink (bottle of wine the night before) and how much I drank in general, (I halved it to 4 bottles a week). He told me to cut down, of course! I know it was the CDT levels, I'll have to find the copy, I think it might have had the percentage figure on there.

Basically, I've cut down to about half my normal consumption over the last two months so it might be borderline or over. I tried to abstain but had a few 'blips' as going through a lot of personal problems.

I'll read through your posts, what was the heading? I don't know if the results will be in yet but I will see about doing it next week. I would rather know one way or the other asap.

 

[white43]

Have a look through this :

http://www.forum.drinkdriving.org/general-discussion/79042.htm

 

[shouldaknownbetter]

CDT is not measured that way(50/100). It could be your GP was giving you Liver Function Test results - which aren't measured anymore for DVLA purposes. A lot of GP's don't seem to be clued in to the CDT test.

If you look at my other thread, you can contact DVLA and get results of your blood test.

I agree with white43, the result you have quoted is in relation to LFTs, which include tests for several substances including ALT, ALP, AST, bilirubin and gamma-GT, all related to liver health and function.
As the 'normal range' is generally quoted as 8-65 U/L, the result you have quoted there is probably for gamma-GT. GGT is often looked at as an indicator of excessive/high alcohol consumption, especially in conjunction with abnormal levels of one or more of the other substances tested.
DVLA previously tested for gGT, ALT, AST and mean cell volume (MCV). However, abnormal levels of ALT etc. can be indicative of other underlying issues, not necessarily alcohol related.

Carbohydrate deficient transferrin (cdt) is the substance that the DVLA test for when analysing your blood sample which is a generally reliable indicator of excessive alcohol consumption as it is very rarely affected by other medical conditions (although some individuals seem to have unwaveringly low CDT readings, see white43's consistently low privately conducted CDT tests).
Generally CDT is not run in the normal array of liver function tests as is indicated by virtually everyone who has visited their doctor for advice and the GP has no idea that it is CDT that is tested for and not gGT, effectively sending blood samples for the wrong tests.

CDT levels are represented as a percentage. In my case 1.0%, 0.9% in several other poster's accounts. For the purposes of the DVLA medical, anything under 2.2% is considered to be in the 'green zone'. 2.3%-2.9% is 'amber', prompting further enquiries and above 3.0% indicates consumption of a dependant nature and refusal of the license issuance.

 

[Kk13]

CDT measures the amount of deficient transferrin in your blood. Alcohol depletes the transferrin of carbohydrate, so the more you drink, the heavier the drinking, the longer the duration - the higher this will make the percentage.

A normal reading of CDT would probably be 1% or lower.

It is theorised that sustained drinking over a two week period of say a bottle of wine a day could push up your CDT level to 3%.

Without knowing what your GP determines as 'normal', it's difficult to say what they deem as 'double' what it should be.

Also - without knowing what you are drinking and with what regularity, it's impossible to say that your CDT levels will come down, it doesn't take much to push it up, as above. The only sure way to bring CDT down is to abstain from drinking for at least two weeks. This should half your current CDT level.

If you are approaching a DVLA medical, you really should abstain and not play CDT-roulette. Recent readings suggest 4 weeks of abstinence will bring your CDT levels down to passable levels.

I have just had my test bk 1.0% still refused my license don't no what's gone on

 

[Kk13]

CDT measures the amount of deficient transferrin in your blood. Alcohol depletes the transferrin of carbohydrate, so the more you drink, the heavier the drinking, the longer the duration - the higher this will make the percentage.

A normal reading of CDT would probably be 1% or lower.

It is theorised that sustained drinking over a two week period of say a bottle of wine a day could push up your CDT level to 3%.

Without knowing what your GP determines as 'normal', it's difficult to say what they deem as 'double' what it should be.

Also - without knowing what you are drinking and with what regularity, it's impossible to say that your CDT levels will come down, it doesn't take much to push it up, as above. The only sure way to bring CDT down is to abstain from drinking for at least two weeks. This should half your current CDT level.

If you are approaching a DVLA medical, you really should abstain and not play CDT-roulette. Recent readings suggest 4 weeks of abstinence will bring your CDT levels down to passable levels.

My cdt test came back 1.0% an still refused

 

[price1367]

My cdt test came back 1.0% an still refused

You are posting on comments made in 2016, and the CDT scales quoted reflect accurately what DVLA standards were then.
Now they are much lower. If you have been previously classed as alcohol dependent, they they are looking for evidence that you have been abstaining from alcohol, which requires a reading of UNDER 1%.
Your score of 1% does not indicate dependence, but is incompatible with a previous dependence classification.

 

[Kk13]

You are posting on comments made in 2016, and the CDT scales quoted reflect accurately what DVLA standards were then.
Now they are much lower. If you have been previously classed as alcohol dependent, they they are looking for evidence that you have been abstaining from alcohol, which requires a reading of UNDER 1%.
Your score of 1% does not indicate dependence, but is incompatible with a previous dependence them

 

[Kk13]

Ye previously 2018 my past is my past do not judge me on my past get it right mt ye no ppl like you piss me off you go take a test bet ye I beat yeah doctors police surgeons the ppl 2ho teach your kids will have a higher score

 

[AndyJG]

Ye previously 2018 my past is my past do not judge me on my past get it right mt ye no ppl like you piss me off you go take a test bet ye I beat yeah doctors police surgeons the ppl 2ho teach your kids will have a higher score

Get that chip off your shoulder.and listen to price 1367. who is probably the most helpful and knowledgeable person on this forum...!

 

[Kk13]

No

Get that chip off your shoulder.and listen to price 1367. who is probably the most helpful and knowledgeable person on this forum...!

No Chip on my shoulder Andy do ye feel like ye banging ye head a brick wall again an again I have done every thing that am asked off they go bk a year on blood I no that's that's not worth the law they say it my letter 1.6% for high risk end off

 

[AndyJG]

No

No Chip on my shoulder Andy do ye feel like ye banging ye head a brick wall again an again I have done every thing that am asked off they go bk a year on blood I no that's that's not worth the law they say it my letter 1.6% for high risk end off

I have not got to the stage of having a medical, as I have six months to go before I can apply for my licence back.....but I am relying on advice from posters on this forum, to be in the best position possible to obtain my licence back......its nobodies fault on here that you havent got your licence back.....its between you and the DVLA..

 

[price1367]

Ye previously 2018 my past is my past do not judge me on my past get it right mt ye no ppl like you piss me off you go take a test bet ye I beat yeah doctors police surgeons the ppl 2ho teach your kids will have a higher score

Wow, don’t shoot the messenger!
What I said is not what I think is fair or even right, but the situation that you face with DVLA... you said : “ don't no what's gone on“ and I took the trouble to explain what DVLA want from a person previously classed as dependent. They ask your GP about your past history of alcohol issues in the past 6 years.
I admire people who get to grips with their issues about alcohol, but DVLA are cautious because people can, and do, lapse and they want to be satisfied that a person is safe to be reissued their licence.

 

[BillyBanner]

Wow, don’t shoot the messenger!
What I said is not what I think is fair or even right, but the situation that you face with DVLA... you said : “ don't no what's gone on“ and I took the trouble to explain what DVLA want from a person previously classed as dependent. They ask your GP about your past history of alcohol issues in the past 6 years.
I admire people who get to grips with their issues about alcohol, but DVLA are cautious because people can, and do, lapse and they want to be satisfied that a person is safe to be reissued their licence.

Hi

I am planning to abstain from drinking for at least 4 weeks prior to my medical to reach passable CDT level, but 4 years ago on my GP record I had history of high level of gamma GT (200+). Would I get refuse? I am planning to get a new gamma GT test a week before medical. Please let me know. Many thanks.

 

[price1367]

See the reply under the same question you asked in: “ If CDT is ok, would high level of Gamma GT get me trouble?”

 

[Kk13]

I have not got to the stage of having a medical, as I have six months to go before I can apply for my licence back.....but I am relying on advice from posters on this forum, to be in the best position possible to obtain my licence back......its nobodies fault on here that you havent got your licence back.....its between you and the DVLA..

Not worth goin on a bout it how many lft tests at my doctors would be considered as evidence

 

[BigTom]

Not worth goin on a bout it how many lft tests at my doctors would be considered as evidence

You keep asking the same questions and keep posting the same rant about being refused with a 1% reading. Numerous people have told you the same, if you were classed as dependent previously and your CDT indicates that you have not been abstinent, DVLA will refuse your licence. It doesn't matter how many LFT's you have to show your liver health, if you have had a drink when you were specifically told not to drink for 12 months if you wanted your licence back then you're stuffed!

For DVLA, LFT's are not evidence of anything (apart from the health of your liver at that point in time), DVLA MAY use LFT's over a period of time to indicate that you have not got liver disease that may have been caused by alcohol, this is always coupled with other information such as CDT, GP's report, other agency inputs etc.