Pain is not a purely biological phenomenon: discrimination, anxiety around work, and general mental strain have all been shown to contribute to the experience of chronic pain. Many researchers therefore take a biopsychosocial approach, exploring the multifarious factors that impact on and are impacted by pain.
A new study in Stress & Health explores the long term consequences of social factors on pain. The team, from the universities of Georgia and South California, Los Angeles, specifically focus on families involved in the 1980s “farm crisis” in the US Midwest, a period where many lost their jobs, land value crashed, and businesses failed — and finds that this financial stress is related to the experience of pain nearly 30 years later.
Data was taken from a longitudinal study, which took place over 27 years and involved 508 married couples, who were all in early midlife at the start of the study in 1991.
The team tracked a number of measures for the study. A four-item scale measured family financial strain in 1991, 1994 and 2001, and participants also answered items related to financial stress (e.g. “we have enough money to afford the kind of clothing we need”) at the same points. Sense of control was measured ten years apart, in 1991 and 2001, with participants indicating how much they agreed with statements such as “sometimes I feel that I am being pushed around in life”.
Pain was assessed at two points later on in the study, with participants indicating how much pain they had experienced in the previous month, how severe that pain was, and how much it interfered with life and work. Participants were also presented with a list of nearly 50 physical health conditions and asked to indicate which they had experienced in the last year; these ranged from common colds to cancer.
The team found a correlation between family financial strain and a sense of control at all points — that is, those who experienced financial strain also felt a lack of control over their lives. Financial strain and a feeling of a lack of control at early points of the study were also directly linked to physical pain at later points, indicating that physical pain can be a consequence of stress not just concurrently but many years later. Those with higher family income were less likely to experience physical pain overall.
The trajectories of financial stress over the course of the study were also relevant to the experience of pain. Those who experienced increasing levels of financial strain over the years of the study also experienced a corresponding decline in their sense of control throughout the same period. This was the case even when controlling for other factors, such as age and physical illness, and was also linked to pain at the later points of the study.
It is unclear what is actually driving the link between loss of control and physical pain, however. The team has numerous suggestions: for instance, feeling out of control could lead people to make bad decisions that in turn lead to pain or physical ill health. Chronic stress can also cause long-lasting changes in brain circuits involved in our stress response, so neurological processes could also be involved in producing experiences of pain many years after stress was experienced. Future research could explore these possibilities, as well as other drivers of loss of control.
There are limitations to the findings though. For instance, those with higher family income may have been able to afford better healthcare and make healthier lifestyle choices when it came to diet, exercise, and non-gruelling work practices, which could in turn have made them less likely to experience pain.
Nevertheless, the study does suggest that there is a direct link between loss of control and negative physical and emotional factors. Interventions that increase people’s sense of control may not ameliorate those structural or social factors that cannot be changed, like a poor economy or unemployment, but could go some way to mitigating their physical and emotional impacts.