Many other health conditions (and some medications used to treat other health conditions) can cause mood symptoms. The list of medical problems that can mimic or look like depression is very long, but most things on that list are rare. We don’t recommend testing for every one of those possible medical problems before getting help for depression. Depression is common, and hypoparathyroidism (that’s a mouthful!) is rare. The old medical saying goes: “If you hear hoofbeats, don’t look for zebras.”
Thyroid disease can cause symptoms of depression. And thyroid disease is relatively common, especially in women or people with a family history of thyroid problems. So testing for thyroid problems is one of the few medical tests we often recommend before diagnosing or treating depression.
Looking for a medical problem that lies behind depression makes more sense if symptoms of depression show up in an unexpected or unusual way—like depression for the first time late in life or depression along with other symptoms that point to a specific medical problem. On the other hand, looking for a medical problem causing depression makes less sense if depression shows up in the usual way—like a return of depression following the same pattern it has shown in the past.
If you are concerned about medical problems causing symptoms of depression, the best test is a discussion with your primary care doctor. S/he can ask you about symptoms that might point to some specific medical problem and follow up with a physical examination. If you don’t have a primary care doctor, you should get one!
It’s important to remember that the relationship between mood disorders and other medical problems is not “either/or”. Often it’s “both/and”. People who live with mood disorders are more likely to experience a wide range of medical problems (heart disease, diabetes, arthritis, chronic pain). In those situations, we would say that diabetes or arthritis can cause or increase depression. But that doesn’t mean the depression isn’t real or shouldn’t be treated. In fact, we know that treatment for depression can have side benefits such as reducing pain from arthritis and helping people manage diabetes or heart disease.