I have had an underactive thyoid for at least 2 years, not as yet been treated with any medication. Went to my Doctors and he has referred me to a psychiatrist to check for depression or dementia (I am 45). I mentioned is there any connection with hypothyroidism but he did not seem to think there was any link. I also suffered an early menopause at 39, think my hormonal system is up the creek. Has anyone any advice ... I am so afraid of being diagnosed with dementia. Am finding it so difficult to concentrate, am forgetting things etc. Any advice hugely appreciated.