Researchers report that a marker of biological aging in blood is linked to some depression symptoms but not all. The tests measured aging in certain white blood cells and were better at predicting mood and thinking problems than physical symptoms such as tiredness or poor appetite.
The study used data from 440 women in a long-term study: 261 women had HIV and 179 did not. Depression was measured with the CES-D, a 20-item questionnaire that asks about both somatic and non-somatic symptoms.
The analysis found that aging in a specific white blood cell type, the monocyte, was related to feelings like anhedonia and hopelessness. The researchers say more study is needed before using these tests for diagnosis or treatment.
Difficult words
- marker — a sign in blood that shows change
- somatic — relating to the body and physical symptomsnon-somatic
- monocyte — a type of white blood cell in the immune system
- anhedonia — not feeling pleasure or interest in activities
- questionnaire — a set of written questions to collect information
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Discussion questions
- Do you think a blood test could help doctors diagnose depression? Why or why not?
- Which symptoms do you notice more when you feel low: physical or mood symptoms?
- Why do you think researchers say more study is needed before using these tests?
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