Chronic Local Pain, Especially Headaches, May Not Be the Only Cause of Depression

Abstract

We read with interest the article by Wang et al. on a study of the longitudinal association between pain and depressive symptoms in Chinese adults using data from the China Health and Retirement Longitudinal Study (CHARLS) [1]. Among 6346 patients without depressive symptoms at the start of the study, pain was more likely to be associated with female gender, low educational level, nonsmoking, and living in rural areas [1]. The presence of physical pain was associated with the development of depression over time [1]. In terms of pain location, only headaches were associated with the development of depression [1]. It was concluded that individuals with chronic physical pain tend to be susceptible to depressive symptoms [1]. The study is noteworthy, but some ambiguities should be clarified.

The first point is that the location and intensity of pain were included in the analysis, but not the type and character of pain [1]. Including the nature of the pain is crucial, as it can reveal that a patient is describing a symptom as pain that is actually something else. Some patients may describe pain as what is actually personal problems, psychological issues, stress, chronic overload, depression, anxiety, nausea, or palpitations.

The second point is that neck pain was not included in the study [1]. Alongside headaches, neck pain is one of the most common causes of pain and should have been included in a study on physical pain and depression. Neck pain has many causes and is often a long-term problem that brings with it a number of secondary conditions. For example, chronic neck pain can affect mood stability and disrupt sleep quality [2].

The third point is that “depression” was not specified in more detail [1]. There is not just one form of depression, but several different types of depression, each with unique symptoms and triggers. These different forms of depression include major depression, persistent depressive disorder, bipolar disorder, seasonal affective disorder, postpartum depression, premenstrual dysphoric disorder, and psychotic depression, which also includes psychoses such as hallucinations [3].

The fourth point is that the development of depression over time may not be due solely to chronic pain, but also to several additional factors. Life events, comorbidities, concomitant medications, and habit changes may have contributed to the development of pain over time. Were these additional factors included in the analysis?

The fifth point is that the development of pain over time was not reported [1]. We should know how many patients developed pain in other regions compared to baseline and how many patients experienced a reduction in pain over time due to adequate treatment or the natural course of the disease.

Overall, before attributing local pain to the development of depression, all other factors that could be responsible for the development of depression must be thoroughly ruled out.

Josef Finsterer was responsible for the design and conception, discussed available data with coauthors, wrote the first draft, and gave final approval.

The author has nothing to report.

The author has nothing to report.

The author declares no conflicts of interest.

Data sharing is not applicable to this article as no datasets were generated or analysed during the current study. All data are available from the corresponding author.