Hypothyroid - how to stop weight gain

[Riablo]

My dog Abi is a 3.5 year old miniature poodle who suffers from hypothyroid. My vet tested her thyroid levels in August last year and although still within the normal range he felt it was very low for a dog of her age and given the other symptoms (weight gain, wiry coat, itchy paws) it was likely that she was suffering from hypothyroidism and to try her on soloxine.

Abi is an active agility dog who has been competing successfully a good level. I would not say she is lethargic, but she was definitely tiring more quickly and was slower running (not normal for her brother to beat her to the ball!). She is a very energetic dog so her 'lethargic' is still pretty crazy, but much less crazy than her normal self. Between May 2012 (when we first noticed the symptoms) and August 2013 Abi went from 10kgs to 13kgs. (It is possible that the weight gain is the reason for her tiring easily and slowing up a little).

When she first started the soloxine in September 2013 on 0.3mg a day she had a terrible first couple of weeks displaying arthritis type symptoms and seemed to have a strange autoimmune arthritis reaction. This calmed down after a couple of weeks. She lost 500g in the first month, but after that there was no weight loss and really no change in her condition. She still seemed to be tiring easily.

She had a full blood panel in December and the vet upped her soloxine to 0.5mg. She has been on 0.5mg soloxine since January. She has just been re-blood tested and the vet is pleased, her T4 is upper normal range (36.7 p/mol/l 6 hours after soloxine). She seems to have more stamina, is keeping up with her brother better when they chase each other and her feet have stopped itching (although that may be seasonable...May is the worst time so keeping fingers crossed it will be better this year).  But I am concerned about her weight gain, we have restricted her diet for sometime but really cracked down on this since starting the increased soloxine in January. She has been on a restricted intake of food, limited treats and increased exercise, yet in the 7 weeks since increasing the meds she has put on 1kg. She is now 13.4kg and at her biggest ever.

I'm not sure if this is normal?

I would also be very grateful for ideas of how to control her weight as she is quite over weight and I am worried about the implications this will have on her health as well as her quality of life.

I had some wonderful advice from this forum when she was first diagnosed and thank you for the help that you gave me then. 

[Jo CIMDA]

Hi

It does seem very odd that your girl is putting on weight when she is having the correct amount of Soloxine. I can't imagine she needs more than 0.5mg and if the dose was too high she would lose weight because her metabolism would quicken up and she would become hyperthyroid!   Soloxine is better absorbed on an empty stomach so perhaps (if you don't already) you could give her the tablet 1 hour before food and perhaps you will get more from the dose this way.   Also what might help (again if you don't already do it) is to split the dose and give it twice a day because this give a more even distribution of hormone throughout a 24 hour period. 

I did a quick search to see what may cause a dog to gain weight and you can check out this link, but to be honest I doubt any of the medical conditions apply to your girl.  I'm sure if there was something else medically wrong it would have shown up on the full blood panel.

http://www.petmd.com/dog/nutrition/evr_multi_medical_causes_behind_weight_gain

Perhaps now she is on a higher dose of Soloxine the weight will gradually reduce.  If you feed dried food you could try putting some of it in a Kong so she eats it a bit slower and uses just a little more energy trying to get the food out. I can only suggest you exercise her a bit more and do as you are doing and reduce her food.  Have you tried a reduced calorie food or perhaps you could cut out some carbohydrate.

Please let us know how she gets on.

Jo

[patp]

She is not finding/stealing food is she? Someone else is not giving her treats and titbits?

The lethargy could well be the weight gain causing it. If you imagine carrying a sack of potatoes around it would be similar. We took on a grossly overweight rescue, once, and his energy levels picked up tremendously once we reduced his weight.

[Riablo]

Thank you for the tips on administering the soloxine, I will try splitting it giving half before work and half after work. She normally has it on an empty stomach before breakfast so I will try to delay giving breakfast a bit, although this might be difficult!

Thank you also for the link to other causes of weight gain - it is useful to look at other possibilities and even to rule out some things. In fact the only thing that fits from that list is hypothyroidism. She is also defintiely 'fat' rather then pot bellied, she has a layer of fat across her back, abdomen, all over really and it is sad to see her waddling along a little, compared to her previous lean build, especially as she is still a young dog. My massage therapist says that although she is carrying an excess of weight she is very well muscled so at least some of the weight is from muscle and she is pretty fit, not just carrying a lot of weight and unfit.

My other dog has stomach problems so changing food is a last resort for us as he couldn't eat the new food and we would have to completely segregate them. We feed Fish4dogs salmon and use either ham or chicken for training treats and carrots for chews. We feed very few manufactured treats. We also supplement with a small packet of quick release high energy food on the day of a show, although my understanding is that this is burnt off very quickly. We found that without this 'on the day' help she was struggling to focus and becoming tired. My other concern is that I want to make sure she has enough energy for doing agility so I don't know if a traditional low-cal food would be the right way to go?

I don't think she can be stealing food from anywhere, we have been monitoring her pretty closely. Because of my other dogs stomach problems we try to monitor feed time and although they share between the bowls Abi usually comes out having had less as she likes to take her food into the lounge to eat it and my other dog has eaten more in the meantime. I provide some small treats for my dog walker so I can see how many she uses, I will check she hasn't been giving anything extra and I will also try reducing her rations again.

I am so surprised though, everything has been the same for a long time now and the more we seem to reduce her food and increase her exercise the fitter she becomes the more weight she seems to put on.

Thank yuo for your helpful comments, it is very much appreciated :-)

[Catherine]

A couple of thoughts and questions:
You say her T4 result was 36.7, what is the normal laboratory range? Was it definitely for the MEDICATED dogs' range? I am not sure where you are but in the UK a result of 50 plus would be a better result. 36.7 would be at the lower end of the MEDICATED dogs' range. Just a thought......
Also if Abi now weighs more she might need more Soloxine.
As regards the food, how do you decide how much to give her? I always think the food manufacturers say too much! I would not give her any treats as these can add up. If "treats" are needed I would take dry bits out of her daily food ration. I would also make sure she only eats a set amount and to gradually reduce it for a while.

[Jo CIMDA]

We also supplement with a small packet of quick release high energy food on the day of a show, although my understanding is that this is burnt off very quickly. We found that without this 'on the day' help she was struggling to focus and becoming tired. My other concern is that I want to make sure she has enough energy for doing agility so I don't know if a traditional low-cal food would be the right way to go?

It is odd that she doesn't burn off the fat when she is so active.  Does she still struggle to focus and get tired, or was that before you treated her with Soloxine?  HypoT can affect brain function but if she is being adequately medicated and having normal meals for an agility dog then she should be behave like a normal 'non-hypoT' dog.

As Catherine mentioned, the level for a medicated dog is usually in the upper limit, or slightly over, of the reference range.  Do you have the results of the original blood test that diagnosed hypoT because sometimes a diagnosis of hypoT is made when in fact the dog has a non-thyroidal illness that is causing the TT4 to be low.  Non-thyroidal illness is caused by another primary cause or drugs etc.  It's just a thought because she should be showing signs of recovery by now.

Jo   

[Riablo]

Thank you so much for your help, we really want to get to the bottom of this as still don't think things are quite where they should be.

We split our time between France and the UK which can make things a little difficult, especially as our French isn't great.

Her most recent blood test was in France. It was just for T4 and was taken 6 hours after her soloxine, as far as I can figure out they class anything more than 5 hours after soloxine as 'free' (I assume free of soloxine?). A normal result would be between 7.7-47.6, but for medicated dogs they look for between 20-35, and if less than 5 hours after medication should be between 25-45. So I think my vets estimation of upper normal seems about right, although this is all new to me. My vet normally discusses his interpretation of the results rather than the exact figures, so for example when she was diagnosed he explained that she was still within normal range but very low for a 2 year old smallish dog, although I never found out the actual reading.

The vet has increased her dosage due to her weight gain, she was originally on 0.3mg based on her target weight but he has now increased this in January to 0.5mg until we can get her weight down.

I based her daily feed amounts on manufacturers guidelines and then discussed with friends who feed the same food and try to feed the low end of what they were feeding similar size dogs. She now receives a double handful a day (can't remember the weight off hand!). She is the first dog that we have had weight problems with so it is a bit of trial and error for us. I will try reducing her rations again and re-weigh, in fact the most recent bag of food we have seems to have bigger kibble so I will need to re-weigh anyway.

The treats are a big part of our positive reinforcement for training, she tends only to get them when we are doing agility or clicker work so I tend to think the energy used to receive the treat is weighed up by having it but maybe that isn't right. She would normally have about 100g of ham a week based on normal training, plus some dry treats if we do clicker work.

The energy food started up at shows as she was struggling to concentrate in the afternoons. Everything sort of happened at once as she was a young dog in her first agility season coping with the show atmosphere, at the same time as starting with her hypothyroid symptoms. We also did it because my other dog with tummy problems was too excited to eat all day and then suffered from excess acid. They find the energy food more exciting than normal kibble and their afternoon runs have been much improved since using it so we just carried on. I will try reducing a bit and see how she goes, but I don't know that two 25g bags of food a month would make a huge difference? My instructor seemed to think she would need something extra on show day so I'm never quite sure how much she needs to have enough energy to enjoy her job but not too much.

Focus has been a particular problem this year since re-starting our training in January, she has been more distracted than normal at training, so the increased soloxine doesn't seem to have had a positive impact there, although hopefully she will settle as we get a few more shows under our belt.

I am wondering if there are other things going on other than hypothyroid, or if another medication would suit her better as her symptoms did seem fairly typical of hypothyroid (itchy feet, wiry coat...some tiredness although never what you would call lethargic!).

Thanks again for your help :-)

[Jo CIMDA]

Hi

It is so frustrating when you are trying everything you can and still not getting the desired result. 

Blood should be taken 6 hours post pill because this is the time of peak hormone concentration and after this time the circulating Total T4 (TT4)declines.  The only 'free' term I know is when the T4 is measured without bound proteins and this is termed as Free T4 or FT4.  FT4 actually tells a lot more about the true thyroid status than the Total T4 because it is less affected by outside influences.

I must be honest and say that I am suspicious about the diagnosis given that Abi's initial result was within normal range (albeit on the low end of the range) and she showed no sign of lethargy.  I wonder if the vet only did a TT4 measurement and not an additional FT4 and a TSH.  If this is the case then the TT4 can be low for many reasons other than a primary hypoT.  The TT4 can fluctuate from being on the low side to mid/top range in a well dog.  This is because there are so many non-thyroid  influences that can effect the TT4.   It may be if you tested a few months after the first test it would have been much higher without supplementation with thyroid hormone - who knows?   

A dog with hypothyroidism (a low TT4, low FreeT4 and a high TSH, with clinical signs of hypoT) will usually respond very well to Soloxine. Perhaps within a few days the level of lethargy will improve considerably and the dog will feel much better, but certainly great improvement is seen within one month of starting treatment. The fact that Abi wasn't lethargic etc., and didn't respond  to treatment as you expected, would give rise to wondering if the initial diagnosis was correct.

The three tests listed above should be the minimum diagnostic test and it gives an overall picture of what the thyroid is doing and the result should reflect the clinical signs.  If she was becoming hypoT then it is likely that the FT4 would be on the low side as well as the TT4 and the TSH would be on the rise. The three tests should show if her thryoid was starting to struggle and indicate that she could be heading in that direction.

Sometimes when the response is not as one would expect the Soloxine has to be gradually lowered and eventually stopped over a period of weeks to evaluate the dog again without the influence of Soloxine. Some clinicians use TT4 supplementation as a therapeutic trial but supplementation suppresses any present thyroid function  A dog that is not hypoT but is being treated with hormone supplementation can take a few months to get back to normal because it no longer needs to make its own thyroid hormone and it feeds back to the pituitary not to produce the stimulating hormone, so in effect the thyroid stops working (even though technically it is able to) until the supplementation is reduced or withdrawn.  It maybe that she cannot efficiently metabolise TT4 but that is usually because of an underlying cause.  Does your vet have any other ideas?  Is there any chance you can get a referral to an Endocrinologist?

Here's some info about hypoT.

Jo

Hypothyroidism – An underactive thyroid gland
'More than 95% of cases of canine hypothyroidism are believed to be due to acquired primary hypothyroidism. Destruction of the thyroid gland can result from lymphocytic thyroiditis, idiopathic thyroid atrophy or rarely neoplastic invasion.'  Canine Medicine and Therapeutics by Neil Gorman.
Hypothyroidism or under-active thyroid glands, is the most common autoimmune disease in the dog and is probably evident in most breeds, although the incidence appears to be higher in some breeds than others. This disease is usually a slow process resulting in the destruction of the thyroid glands by antibodies directed against the thyroid (lymphocytic thyroiditis).  As the body only needs less than 20% thyroid production to function, clinical signs of this disease often develop over a lengthy period of time and are so gradual that the owner is not always aware that the dog is slowing down.  The body will cope very well with diminishing thyroid glands, but when the glands have been more than 80% destroyed then clinical signs become more obvious. 
The thyroid is essential to life; thyroid hormones are circulated to all parts of the body. If replacement therapy is not given to a hypothyroid dog it will die.  Usually the clinical signs show well before this time and a thyroid blood test should confirm a diagnosis. Thyroid disease is not always simple to diagnose but usually a low TT4 (total thyroid hormone) confirmed by a low FreeT4 (thyroid hormone measurement without protein) and a high TSH (Thyroid Stimulating Hormone) is considered to be diagnostic of hypothyroidism.  (In addition, tests to assess thyroid dysfunction may include: TT3, FT3, autoantibody, TSH and TRH response tests).
Measuring TT4 alone is not enough to make a definitive diagnosis as the dog could be suffering from a non-thyroidal illness (NTI), that is an illness affecting the amount of thyroid hormone within the circulation, rather than a primary autoimmune destruction of the glands.  Non-thyroidal illness should be suspected if the dog has a low TT4 and a low TSH. Whippets and other sighthounds have a naturally lower TT4 than many other breeds but the FT4 is within normal limits.
Note: Several drugs, including prednisolone, and diseases such as Cushing's syndrome, will lower the circulating TT4 levels and this should be taken into account when evaluating the results.  Hypothyroidism is both over and under diagnosed.

Clinical signs of hypothyroidism are:
Lethargy, mental dullness, unwillingness to exercise,  stiffness in gait – limping, weight gain (obesity), dry scaly skin, dandruff and/or greasy skin, excessive pigmentation (hyperpigmentation),  skin lesions, on-going ear problems, coat texture and colour changes, loss of hair particularly on the tail and bilateral, symmetrical  hair loss, signs of premature ageing, irregular seasons - poor infertility and libido, depression (tragic expression), irritability or aggression, intolerance to cold, seizures, voice change (pitch of bark),  muscle weakness, megaoesophagus (weakness of muscles in the throat causing difficulty in swallowing).
On examination your vet may also find that a hypothyroid dog has a slow heart beat (bradycardia), eye abnormalities such as corneal lipid deposits or ulceration: dysfunction of the central nervous system (CNS), such as tilting of head, circling, unsteady gait (ataxia):  Blood analysis may also reveal anaemia and high cholesterol.
The prognosis for dogs with hypothyroidism is excellent, although life-long daily treatment with hormone replacement, Levothyroxine, is required. Giving half the daily hormone replacement dose every twelve hours provides a more balanced level of thyroid hormone throughout a 24 hour period and avoids peaks and troughs. (BSAVA Small Animal Endocrinology)  "Levothyroxine is better absorbed on an empty stomach".  Canine Medicine & Therapeutics by Neil Gorman
Note: Sometimes dogs with hypothyroidism are prone to other autoimmune diseases.

[Riablo]

I am sorry for the slow reply, we had a busy weekend at a show and then a busy week at work (me not the dogs!).

I am a wondering if the diagnosis of hypothyroid is correct or whether there is something else going on as well. Definitely need to have another chat with my vet and will try to push for a referral. In fact it might even be easier to go to see an endocrinologist here in France and we also live fairly close to a good veterinary university who may have a specialist we see.

There is another possible symptom (although it may not be related at all), Abi has urinated in the house 3 times in the last month. This is very unusual for her. Twice she has done it on our bed and we haven't noticed until later and once she did it right in front of our eyes in the lounge. She was lying on the floor happily and then suddenly huddled and did a massive wee. She looked mortified and embarrassed. Didn't seem like incontinence so much as she had no warning that it was coming. The weeing on the bed could be more of a territorial thing, we only let the dogs on our bed when we are there and each time she has wet on it has been when we have accidentally left the door open. Has anyone experienced these kind of changes with hypothyroid?

Unfortunately have had problems getting her medication shipped from the UK so eventually, after 2 hours of trying, managed to get hold of some generic thyroxine. Not sure if there is a link but she has been being sick daily since starting the new drug. Hoping the soloxine prescription arrives in the next few days and we can get her back on track. In the meantime we have further reduced feed rations. She is on Fish4Dogs. The feeding guidelines are really vague dogs 1-15kg should have between 35-200g food per day. Abi is 13.4kg and should be about 11kg so we were feeding 130g a day and have now reduced to about 110g. Not sure if that still sounds too much? Never sure how much is the right amount. Sometimes they finish it in one go and other days they leave some, it varies.



From an activity point of view at the show she was very full of beans. First show of the season so a bit excited to begin with but settled well for her second class and a good quick round, had a few energy biscuits at lunch and then won her after lunch class and did a fast round in her final class. So speed and stamina looking good and her focus was good as well.

Thanks again for all of the information it is much appreciated.

[Clover]

Hypothyroidism can cause incontinence, if she's not getting correct levels of her medication it could certainly cause the bed wetting.

It sounds like the new drug really does not agree with her, the coincidence would point in it's direction for sure.

Here's a link for you that has some in-depth information, from a pioneer in the research field: http://drjeandoddspethealthresource.tumblr.com/tagged/thyroid#.UyD2eYVoHDc

[Jo CIMDA]

Hi

Has Abi been spayed?  This can cause incontinence.

Is she drinking more than usual?

Jo

[Riablo]

Hi

She has been speyed, she was speyed at 6 months and she is nearly 4 now so not sure if incontinence normally comes on all of a sudden like this. Also would it normally be a little leakage of urine or huddling down to do a full wee?

She isn't drinking anymore than normal.

[Penel CIMDA moderator]

She could have a low grade urine infection.  Perhaps take a sample in to the vets?