Hypos: tighter control & its impact
adjusting insulin dose pages from DAFNE
- fitting in tighter control into your lifestyle
- why do hypos happen?
- impact of hypoglycaemia
- why do hypos happen
- warnings of hypos
- losing warning feeling of hypos:
- hypo-unawareness, possible causes
- who is at risk?
- should I improve my diabetes control?
- when is tight control not advisable?
- defining your 'lower limit'
- avoiding too many hypos
- prepare for hypos
- what to do if you get a hypo
- treatment of hypo-unawareness & frequent hypos
- treatment of hypos at night
- achieving success
This page is from various sources.
Remember that you are an important member of your diabetes care team - you will have a better chance of success if you all work together as a team. You may need extra support and advice from your diabetes care team on how to maintain good control.
Your current level of control will be based on your HbAlc level. This is an average of your blood glucose levels over the last 6-10 weeks. If you want to start making improvements, discuss your plans with your doctor or nurse first and agree on an target you can reach with them.
Try to improve your lifestyle generally. Focus on healthy eating and regular exercise. Decide what is best for you with your doctor.
In the DCCT, people in the intensive group gained an average of 10 lbs. more than those in the standard group -you might be able to prevent unwanted weight gain by fine tuning your eating habits. Your dietician will be able to advise you about healthy eating. The new insulin Levemir/detemir may prevent this...at least this is what one manufacturer says.
Keep records of your activities, the food you eat, your blood glucose levels and the amount of insulin you inject. These records will enable you and your diabetes care team to establish a pattern and help you to get the best possible control.
Be honest with yourself and your diabetes care team. For instance, tell your doctor if you know that you won't take exercise, otherwise you will set yourself up for failure from the start.
Be prepared to experiment with your control while you learn what is best for you don't expect to achieve good control from the word go; changes always take time.
Remember that with tight control hypos can happen very fast meaning that you may not always have time to test your blood. Be aware of the warning signs such as sweaty hands, increased heart rate and shakiness. Tell your doctor if you are not experiencing warning signs, especially if your insulin dose has been changed recently.
If you have tightened up your control, remember to test your blood glucose level before you drive - low blood glucose when driving could cause an accident.
Be prepared for hypos by making sure that you always have some glucose with you.
Tell your family and friends what you are doing - they won't be able to support you if they don't understand why you are monitoring, for example, and what the information means.
Expect to have hard days as well as good days - getting through will make success at the end seem even better!
A hypo is defined for patients as a sugar less than 3.6 mmol/l. However, technically you do not get symptoms with a sugar below 3.5mmol/l, and you may not need to take corrective action unless your sugar is <3.5mmol/l, but particularly <3.0mmol/l.
- too much insulin
- inappropriate insulin regimens (incorrect doses and insulin types)
- injection site problems
- too little food
- more exercise than usual
- this may cause a hypo in the night or the next morning after exercise the day before
- consider having a complex carbhoydrate if going out drinking (eg crisps or a snack)
- it delays gluconeogenesis
- less commonly, other illness such as coeliac disease, thyroid, addisons, gastroparesis (digestion problems), psychological problems
- changes in insulin sensitivity (including drugs affecting the renin-angiotensin system and renal failure)
- they are much commoner if patients have renal problems having had diabetes for many years.
Hypoglycaemia (low blood glucose) occurs whenever there is more insulin in the body than is needed. It is usually uncomfortable rather than dangerous, but occasionally blood glucose goes so low that the brain runs out of fuel and ceases to work properly. Confusion, irritability, even unconsciousness, can result.
A severe hypo leaves the person with diabetes unable to help him or herself and needing help from someone else. This unpleasant, embarrassing and potentially dangerous complication of insulin treatment is not very common. However, those people on intensive insulin treatment are at greater risk. Why?
Hypo warning symptoms
Usually, your body recognises a small fall in blood glucose and tells you about it long before you have any confusion or inability to cope. Early warning symptoms of hypos include feeling sweaty, shaky, hot, cold, anxious, very hungry or drowsy. You may also lose your concentration, have difficulty speaking and become irritable.
When you feel these symptoms, you should (ideally!) check your blood glucose and if it is low, correct it by eating something rich in carbohydrate immediately. You are only at risk of greater confusion and perhaps loss of consciousness if your blood glucose continues to fall.
Some people lose their early warning symptoms of hypoglycaemia. About a quarter of all people who have had diabetes for a long duration (say more than 15 years), find their hypo symptoms have changed so much that they may miss them altogether. But loss of warning of a hypo does also seem to be more common in people using intensive insulin treatment and may contribute to the increased risk of severe hypos.
This is partly because there is less leeway with tight diabetes control; if your background blood glucose is nearly normal, a small drop in blood glucose, perhaps from unexpected exertion or a late snack, may take you really low. As a result, you may be too confused by the time the symptoms arrive to recognise them for what they are. See case
A common reason for having too many hypos that you are not aware of is that you are simply having too many, and your body cannot cope, wearing out (temporarily) the body's warning system. The repeated undetected periods of hypos (<3.5 mmol/l) often for extended periods, commonly at night.
When hypos are serious are frequent, review possible contributory causes (NICE 2004):
- inappropriate insulin regimens (incorrect dose distributions and insulin types)
- meal and activity patterns, including alcohol
- injection technique and skills, including insulin resuspension
- injection site problems
- possible organic causes including gastroparesis
- psychological problems
- previous physical activity
- lack of appropriate knowledge and skills for self management
- changes in insulin sensitivity (including blood pressure drugs and renal failure)
This review needs to be carried out with the help of your diabetes nurse /doctor. If the cause is unclear, and glucose monitor may help. These can monitor glucose levels overnight, and l can tell your nurses when your hypos are coming.
Hypos are slightly more common at night. About half of the daytime episodes apparently occurred without proper warning symptoms. Severe hypos are more common with intensive insulin treatment....for every 1% lowering of glycated haemoglobin (HbAlc), there is a 36% increase in risk (DCCT).
A hypo can occur at high glucose levels. If a person normally has a glucose level of 15mmol/l, then even a drop to 10 can cause a hypo. Commonly, if the glucose is normally 9, then a level of 5 may cuase a hypo.
However, the most serious hypos occur at much lower glcuose levels. So if a peson is very well controlled, with normal glucose levels of 5-6mmol/l, the such a patients will occur is levels drop to2 or less (and at this level the hypos may be severe with unoncsiousness) .
Generally the risk of hypos should not stop you trying to improve your control. We have learnt a lot about hypos and what contributes to the risk of having severe ones. In the DCCT itself, the frequency of severe hypos declined as time went on and people started to understand the causes of severe hypos.
People on tight control in the DCCT who experienced more hypos said that hypos did not affect their quality of life. But there are some groups of people who should be wary of keeping their blood glucose levels too tightly controlled because of potential hazards should severe hypos occur. They include:
There is no proven advantage either for people who already have advanced complications such as severe visual loss or kidney failure (though there were no such people in the DCCT).
Including a lower limit in definitions of 'good' diabetes control is very
The DCCT researchers decided that very low blood glucose levels (around 3-4 mmol/l) were something to be avoided and that blood glucose should be kept above 3.6 mmol/l in the middle of the night. Research studies have shown that eliminating hypoglycaemia from daily life may even restore warning symptoms of the occasional hypo that may creep in!
Think about (and check) your blood glucose readings when you think you might be most at risk.
- Hypos at night may not produce symptoms but may be enough to cause loss of awareness to day time hypos too.
- Vigorous exercise in the day may increase the risk of hypoglycaemia during the night.
- The time between meals is another thing to watch. If your glucose levels are normal immediately after a meal, you may well hypo before the next meal if you exercise or miss your snack.
- Remember too that blood glucose levels of less than 3.5 mmol/l do not occur in people who do not have diabetes. If you see several of these low values when you check your blood glucose at home, try and adjust your regimen so that they don't happen in the future. Your clinic will help you. See also testing your sugar
Alcohol increases susceptibility to hypos as it affects glucose metabolism and reduces the warning signs. Binge drinking is dangerous in diabetes, but if you 'have to' binge drink, maintain higher than usual glucose levels, and test your glucose levels more often, especially in the night after the binge.
Discussed in more detail here. If you play a round of golf for instance, to prevent a hypo you should reduce the dose of the previous insulin injection, both short and long acting types. If you forgot to do this, or did not have chance to plan ahead, expect a hypo: test your sugar before and half way round if you get the chance, but if not have something extra to eat before you start, and half way round. Test when you finish, as you may need something to eat then as well.
If you have a lot of vigorous exercise during the day, you need a lot less insulin (a 30-50% reduction may be needed). If you do not have chance to reduce your insulin both in advance and after the exercise, you may get a hypo in the evening or even in the night. So reduce your insulin, and eat more, and test often. (Even in the evening after the vigorous exercise.)
Eventually you will learn how to make the adjustments and have very few hypos, but it takes a lot of practice and testing, and advice from you diabetic nurse. Try and increase your exercise gradually to avoid this. If you exercise at weekends only, and have a desk job during the week,remember you will need vastly different insulin doses at the weekends. With planning, testing, and adjusting doses, good control is still achievable.
As mentioned, when you have an infection your sugar goes up and you need more insulin. When the infection goes you will have to reduce your insulin, so be prepared, test, adjust, and look out for a hypo.
If you are driving, always have a few cartons of orange juice with you. A salad sandwich or fruit would be useful as well, reserving sweets as a last resort. If you are changing your insulin regime, have taken more exercise than usual, or feel sick, a hypos may be more likely. Generally insulin users should test their sugar level before starting to drive and every 90 minutes.
Hypo treatment.... lucozade, carton orange juice, dextrose tablet, followed by complex carbohydrate such a a bananan or sandwich. Naturally this depends on the hypo, and it is better to try and predict one and take preventative action. In practice many people with diabetes do notice occasional hypos, even if they try really hard to avoid them. If you think you are getting hypos regularly YOU MUST TEST YOUR SUGAR to confirm they are hypos if you are to have any chance of controlling your diabetes properly.
if you think you might be getting one, test your sugar if you can. If you cannot test, and particularly if you are driving, you will need to drink or eat
a small carton of orange juice has enough sugar in to make your sugar rise; this might be enough for a mild hypo. Dextrosol tablets in the car can be helful. Chocolates or sweets will get eaten before the hypo!
after the orange juice has caused the immediate rise, a salad sandwich or banana will help to produce a more sustained rise in sugar
in unusual situations, such as taking far more insulin than you needed, or having a lot more exercise than you are accosted to, even this will not be enough, and you may need more food
in an emergency sweets help, as does Glucostop. This can be given my carers, especially if the patient is not completely unconscious.
A whole mars bar though contains enough sugar to destabilise your diabetes for days. A small sweet or half a mini-mars bar followed by a fruit or sandwich would be better.
if you are unconscious a carer can give you a glucagon injection, and when you wake up, you need a drink and some food. This is a very serious situation, an expert advice is needed, and sometimes an emergency paramedic will be needed.
3 dextrose tablets may suffice, probably followed by more complex carbohydrate such as a sandwich or banana. Chocolate and biscuits are not ideal (but may work in an emergency).
A glucagon injection can be injected by someone else if you have a severe hypo, although you need a sugary drink afterwards. Intramuscular glucagon (0.5-1mg...the higher dose may produce vomiting particularly in children).
It is not effective in alcoholics. After recovery, have some oral carbohydrate,
such as a sugary drink or orange juice, followed by a sandwich or some other
carbohydrate. There should be a response in 10 minutes (otherwise intravenous
glucose is needed.)
This website cannot advise relatives when to call a paramedic, but if you are not sure what is going on, it is best to call for urgent paramedic help.
After recovery from the glucagon you need to contact your nurse/doctor for advice.
You will need expert help from your nurse and doctor
The newer insulin regimes which are based on glargine or detemir are likely to be very helpful, especially in reducing night time hypos.
Night time hypos..make sure you are using the newer glargine or detemir insulins.
If your hypo is related to exercise, clearly you have not adjusted your insulin enough..you needed less insulin before the hypo, see
For frequent hypos that you are not aware of, try and reduce your insulin, all doses, for 4-6 weeks (with expert help). Gradually your hypo symptoms should return, and then you can start to very gradually increase your insulin doses, with expert help.
Some people say they get hypos at higher levels of 6 or 8. Generally expert help is needed, but in practice it is very usual to get a 'hypo' at a level of 8...you may be noticing another problem.
Unconscious patients, see NICE pdf document page 90
Whilst seeking help for your doctor and nurse, if you think insulin is the cause:
reduce most of your insulin doses 2-4 units
test frequently, 6 times a day
your tests should then reveal no hypos, otherwise you may have to reduce your insulin more
when your body adjusts to the higher sugar levels, perhaps in a 2 weeks or so, you should start to recognise hypos again. You need to keep testing your sugar levels.
Gradually increase your insulin levels so that your sugar reaches reasonably low levels, but not the very low hypo levels you had before.
Primary care teams are not expert enough at tackling such problems BMJ 2011
If the diabests is well controlled, then hypos might be more severe as the glucose level will be lower (affecting the brain more). Poorer controlled patients get hypos at a higher glucose level.
Hypo unawareness may be reduced with a islet cell transplant. Hypo unawareness after 30y of diabetes might be impossible to remedy.
Hypos occur often at night. They seem particularly common post-pregnancy, when a women wants good control, but the control may be too 'good'.
Hypos at night may be noticed by patients or detected by implantable monitors (available for a few days from hospital diabetic clinics) should be managed by:
- reviewing current insulin regimes, evening eating habits, and previous physical activity
- choosing an insulin type and regimen less likely to cause a low glucose
levels in at night, such as:
- rapid-acting analogue with the evening meal
- long-acting insulin analogues Lantus/glargine & Levemir/detemir
- insulin pumps
What if you have had bad hypos recently and are afraid of trying to lower your average blood glucose level? Suppose you've dealt with the problem by relaxing your diabetes control until your blood glucoses are always high (say over 9 mmol/l) and you've stopped the hypos but now have a high HbAlc with its increased risk of long term diabetes complications.
Remember that the risk of diabetes complications is almost directly related to the value of the glycated haemoglobin (HbAlc) and almost any reduction In average blood glucose and HbAlc will now be useful.
Don't give up just because you despair of perfection - it is worth lowering your HbAlc as much as you can without starting to hypo again. And look very carefully at the spread of your home blood glucose readings -getting rid of those under 4 mmol/l readings may be all you have to do!
We now know that the better your blood glucose control over the years, the better your chances of avoiding diabetic complications. And we also know that really good control means avoiding hypos too --both the severe and mild ones. Visit the AIDA computer model of insulin/sugar levels.
No driving if more than 1 severe hypos in one year (must notify the DVLA).
If using drugs that can cause hypos (insulin particularly), test glucose before driving and every 2 hours driving, keep the results on a meter. The meter and its results will be examined by the police if there is an accident. The meter must keep results for the weeks before also (for the police if needed).