Depression affects nearly 280 million people globally, according to the World Health Organization, and it is approximately 50% more common among women than men. Unfortunately, part of the reason for its prevalence could be due to misdiagnosis. According to an article in Current Psychiatry, 26%-45% of patients referred for depression do not meet the diagnostic criteria for the illness. In another analysis of 118 studies, researchers found that general practitioners correctly identified depression in only 47% of cases and they often diagnose it in people who don’t have it.

The difficulty in correctly diagnosing clinical depression is that it often overlaps with other psychiatric and physical conditions. There isn’t any definitive test that can diagnose depression — providers diagnose it when a patient has five of nine specific symptoms that last longer than two weeks — so a true diagnosis should require the elimination of other potential causes. 

The unfortunate truth of our medical system is that many doctors don’t have the time or ability to really work through what could be causing the symptoms, so it’s important that you have some of the facts before simply accepting a depression diagnosis for you or a loved one.

Depression Symptoms

The diagnostic criteria for depression require a patient to have at least five of the following symptoms for two weeks or longer:

  1. Feeling sad or having a depressed mood
  2. Loss of interest or pleasure in activities once enjoyed
  3. Changes in appetite/weight loss or gain unrelated to dieting
  4. Trouble sleeping or sleeping too much
  5. Loss of energy or increased fatigue
  6. Increase of purposeless physical activity (inability to sit still, pacing, hand-wringing) or slowed movements or speech (these actions must be severe enough to be observable by others)
  7. Feeling worthless or guilty
  8. Difficulty thinking, concentrating or making decisions 
  9. Thoughts of death or suicide

Possible Depression Mimics

While it’s certainly true that people over 50 can experience depression, it’s especially important to consider other possible diagnoses in older adults. Chronic medical conditions, early dementia, hearing and vision loss, and medication side effects can all mimic the symptoms of depression. Here are a few of the common culprits:

  • Anemia

Anemia is a condition in which there aren’t enough healthy red blood cells to deliver oxygen to body tissues. This leads to weakness, fatigue and difficulty concentrating, which are also telltale signs of depression. 

Your risk of anemia increases with age, and it is especially prevalent in people over 65, according to the CDC. And to make things even more confusing, untreated anemia can lead to depression. 

• Cancer

Some of the symptoms associated with early stages of cancer — loss of appetite, weight loss and fatigue — can be mistakenly attributed to depression. In 2016, a Swedish study of 300,000 cancer patients and more than 3 million cancer-free patients found that the cancer patients were more likely to be diagnosed with psychiatric disorders in the 10 months before their cancer diagnosis. This suggests that depression could be a possible early signal that a disease process is at work in the body. (Or, conversely, that it could be a common premature misdiagnosis).

Another study has found that the link between depression and cancer is particularly strong with pancreatic cancer. Two review studies have found that between 33%-45% of pancreatic cancer patients reported psychiatric symptoms before their medical symptoms.

• Diabetes

According to the CDC, 1 in 5 people with diabetes don’t know that they have the condition. 

Both diabetes and depression can cause patients to experience weakness, fatigue, irritability and unexplained weight loss. Studies also show a strong link between depression and diabetes, but the connection is not fully understood. The stress of living with diabetes could lead to depression, but it’s also possible that diabetes leads to other health problems that worsen depression symptoms. Either way, if you are experiencing depression symptoms along with excessive thirst or hunger or other symptoms, be sure to test for diabetes.

• Vitamin Deficiency

About 35% of U.S. adults don’t get enough vitamin D, according to the Cleveland Clinic. Lack of this vital nutrient, usually obtained by spending time in the sun, can cause low energy, difficulty sleeping, mood changes and weakness. A vitamin B12 deficiency can similarly lead to symptoms that look like depression or dementia.

• Thyroid or Parathyroid Problems

The thyroid is the gland responsible for producing hormones that regulate almost all of your metabolic processes, affecting heart rate, appetite and energy levels. An under-active thyroid can cause fatigue, feelings of sadness and irritability, insomnia and weight changes. Similarly, if you have an overactive parathyroid it can lead to an excess of calcium in your blood (hypercalcemia), which can also cause depression-like symptoms. 

• Medication Side Effects

As we get older, it seems like we need to take more and more medications to stay healthy. This could be a problem, though. According to one study, about a third of Americans are taking a prescription medication that could potentially cause depression or symptoms of depression. Common culprits include steroids, anxiety and seizure drugs, and opioid pain medications.

If You Are Concerned

If you are experiencing symptoms of depression, speak with your medical provider. However, think about asking for tests to rule out these common depression mimics. Something like a vitamin D deficiency is easily remedied, whereas clinical depression can be a debilitating condition and one that isn’t always easy to treat successfully.

Top image by LightFieldStudios from Getty Images, via

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