How does Hypothyroidism relate to bipolar disorder

I,ve been married for 12 years to a woman who I have always thought to be bipolar.  Major mood swings, verbal abuse, contolling and manipulative behavior, lying and an overall sense of unhappiness. I have just learned that she is being treated for thyroid disorder (hypothyroidism) and is taking Synthroid for treatment. She still acts the same as above but now even more amplified. She is so irritable and depressed that I think she might be crazy. Does Hypothyroidism relate to Bipolar Disorder ?

[ILADVOCATE]

An abnormally low thyroid level can bring on depression. Thyroxine is being used experimentally to treat the depressive aspect of bipolar:
http://home.comcast.net/~pmbrig/BP_pharm.html#thyroxine

[Venora Moonwind]

Hi there I am bi polar as well as throidless. Illadvocate is right that hypothyroidism will cause depression. There is also hyperthyroidism which  the symptoms are much like a manic episode. For example I lost weight and My synthroid scrip sent me hyper and I wasnt sure if  my zyprexa had stopped working or what be cause it was an awfully like being manic( and I do mean awful!!) I suspected my synthroid so I went and had labs drawn and sure enough my TSH was like .01. sending hyper. As soon as I was on the lower dose I started to come down but it took about 3 weeks to begin to feel like my stable self
TSH should be between 3  to 3.4 but every one is different. I feel the best at around 2 and that may be hyper for someonelse
When I researching I found that bi polars are at greater risk for thyroid problems. google thyroid/ bipolar. It was a big eye opener for me.
There is a thyroid disorder forum here and doctor and a patient to patient forum and It is wonderful support for thyroid people. Just click on forums at the top of this page and scroll down
I do know I have been able to reduce my bipolar meds to the lowest dose since I  got my synthroid tweaked just right. so maybe when she gets her levels right some of the depression will be alleviated.
Is she on meds and in any kind of therapy.Bi polars have a really hard time coming to terms with being bi polar and some never do. I pray this isnt the case for your wife.I know how difficult is was me to accept my bi polar diagnosis
Educating yourself is the best thing you can do for her tight now. Try out the thyroid forum and post all you like You can pm me too if I can be of further help I try to come on line in the evening  here in Oklahoma
Blessed be
Venora