It’s long been thought that depression and chronic pain were tightly connected. Both depression and chronic pain are common disorders in the Western world and both play a big role in the lives of patients, health care, and economics for employers. Many studies have found a connection between the two, leading researchers to believe that one influences the other in many patients.
The authors of this study looked at several studies and reviews. They found that some studies did imply that reducing pain would reduce depression and reducing depression would reduce pain. Therefore, by treating the depression, the pain would be managed successfully.
There are some explanations that could give some truth to the belief of the depression and pain connection. Serotonin and nonadrenaline, hormones, do play a role in depression and also in pain. For many people with certain types of chronic pain, antidepressants do help relieve the pain, specifically tricyclic antidepressants and dual reuptake inhibitors. However, the reverse doesn’t seem to be true – researchers haven’t found that pain relievers ease depression. In fact, they could – in some cases – worsen the depression or increase its risk.
Despite the studies showing that depressants can help relieve some types of chronic pain, other studies haven’t come to the same conclusion. Many studies have found that there could be connections between different life experiences and issues, from genetic to psychosocial to role behavior, and yet just as many studies found the opposite.
In this trial, the authors looked to find the relationship between depression and chronic pain using specific measures that have been recognized as being effective measurement tools by the research community. Researchers recruited 273 patients who had chronic pain and who were participating in a pain rehabilitation program. The patients were asked to assess their pain using the Short Form-36 (SF-36), which is the most frequently used survey used to determine a patient’s overall well-being. The researchers also used the Multidimensional Pain Inventory (MPI) to assess pain and its consequences, and the Hospital Anxiety and Depression Scale (HADS), which looks at depression and anxiety. The MPI and HADS scales were modified by the researchers so they were marked on a scale of zero (no pain, depression, anxiety) to 100 (the worst ever pain, depression, anxiety). The SF-36 pain scale was also zero (no pain at all) to 100 (worst pain ever), as was the SF-36 physical functioning scale.
There was a great range among the patients regarding how they rated their pain and depression with the MPI and HADS. However, there didn’t seem to be any correlation between how they rated their pain and how they rated their depression. Some patients rated their pain to be close to 100 while depression close to zero, and the other way around. There were enough patients who did rate higher pain and depression levels to allow for a weak association between the two, but this wasn’t strong enough to say that the two are definitely related. The researchers did find some relationship between patients who catastrophized their pain, thinking the worst would make the pain worse or bring it back, and pain level.
Pain management programs designed to help people manage their pain can approach management in many different ways. The researchers wrote, though, that all such programs should include interventions that look at and treat, if necessary, other issues, like depression or anxiety. The researchers found that there was a connection between anxiety and function, so if the patients are experiencing outside stressors, such as family issues or marital problems, these need to be addressed in order for pain to be treated.
The researchers concluded that there was not a strong basis behind the theory that depression and chronic pain are related, however if someone is stressed, this could have an impact on pain management.