Medical experts are calling on doctors across the UK to routinely offer thyroid tests to patients struggling with anxiety and depression. They told The Mail on Sunday that psychological disturbances are a massively under-recognised and misdiagnosed symptom of hypothyroidism, an underactive thyroid condition affecting around 1.4 million people in the UK.
Jim Harwood, a 73-year-old computer programmer from Pinner in north-west London, found himself intensely stressed and angry about trivial things completely out of character. Someone pushing a trolley in front of him in the supermarket or a minor error by a work colleague would trigger a harshly worded outburst that he immediately regretted.
At the same time, the razor-sharp focus and intense concentration he had always relied on as a programmer began deserting him. He struggled to keep his mind on the job, remember names, and control his words and actions. "I just didn't know what was happening to me. I had a level of irritability - of stress and anxiety - that I just couldn't explain," Harwood said. He considered possibilities ranging from the onset of dementia to mad cow disease, but never suspected his thyroid. "It just wasn't something I suspected," he said.
Expert calls for routine thyroid tests
Kristien Boelaert, professor of endocrinology at the University of Birmingham and a trustee of the British Thyroid Foundation, said hypothyroidism often goes undiagnosed. "So if people go to their GP with anxiety or depression - especially if they are showing any of the other more commonly recognised physical symptoms - then doctors should be prepared to suggest tests for thyroid function," Boelaert said.
The thyroid gland is a small butterfly-shaped organ in the neck located just in front of the voice box that produces crucial hormones needed to keep the body healthy. In hypothyroidism, levels of these hormones are too low, leading to physical symptoms including tiredness, weight gain, feeling cold, constipation, dry or thinning hair, muscle weakness, aches, a hoarse voice, and slowed speech and movement.
Because receptors for thyroid hormones are also found in the brain, research shows that hypothyroidism can affect how people think and feel. Lyn Mynott, chief executive of the charity Thyroid UK, said psychological issues caused by low hormone levels are not as widely recognised. "A lot of people can suffer these symptoms for a long time without realising they're suffering from a thyroid disorder," Mynott said.
Risks of misdiagnosis and health complications
Hypothyroidism affects around 2 per cent of the population and is more common in women and older people, affecting around 5 per cent of 60-year-olds and 10 per cent of the over-80s. Mynott said thyroid-related psychological issues are often misdiagnosed, especially in middle-aged women who might think problems stem from busy, stressful lives, or older people who believe it is the start of dementia.
"But even when they do seek help, doctors often miss the real cause, as they don't think to do thyroid tests," Mynott said. "As a result, patients might be prescribed an antidepressant or told to reduce their stress. But if the cause is actually hypothyroidism, these won't help or address the root of the problem."
Experts say undiagnosed hypothyroidism can cause severe heart problems, as insufficient thyroid hormone can slow the heart rate, raise blood pressure, and increase cholesterol in the blood. For women, the condition can disrupt ovulation, alter menstrual cycles, and increase the risk of miscarriage.
Physical symptoms and recovery
In the most severe cases, long-term untreated hypothyroidism can cause a myxoedema coma, a rare but life-threatening condition that causes vital organs to shut down.
For Harwood, doctors only realised his psychological problems were linked to his thyroid when he later developed physical symptoms. "I put on weight - an extra 9kg [20lb] - and found myself becoming profoundly cold," Harwood said. "Even in a heated office I needed to wear a thermal vest under a shirt and sweater. The fatigue was crippling. I could barely function." He also developed a swollen neck.
Harwood was eventually prescribed daily tablets of artificial thyroid hormones, which have almost entirely eradicated his symptoms. "It was only after the physical symptoms appeared that it become clear that hypothyroidism was the cause," he said. "Once I started on the drugs, my mood completely lifted. It was really something. I just wish it hadn't taken so long."
