Chronic pain conditions are characterized by significant individual variability complicating the identification of pathophysiological markers. New research suggests that a biological measurement of premature aging may be linked to fibromyalgia pain.
Fibromyalgia means widespread pain in the muscles, but this syndrome causes many other symptoms. Whether you are experiencing painful tender points, deep muscle pain, chronic headaches, unending back pain, or neck pain, you know how fibromyalgia feels.
The cause of the disease is still unknown, and many researchers have postulated many causes, ranging from genetics to environmental factors. Intriguing new evidence suggests that fibromyalgia may be associated with a marker for biological aging, known as telomere length.
Telomeres are considered an index of cell age and are like a clock of the cell’s lifespan. Telomeres play an important role in a variety of age-related illnesses, including cardiovascular disease (e.g., stroke, heart attacks), diabetes, osteoporosis and several forms of cancer. Shorter telomeres have also been associated with cognitive function, dementia, and arthritis. Sex, race, socioeconomic status and even level of education appear to affect the length of a person’s telomeres, as do behaviors and physical characteristics such as smoking, body mass index, stress and depression. On the flip-side, long telomeres are related to healthy aging and overall longevity.
To determine the relationship, between telomere length and pain, researchers at the University of Michigan performed a study comparing the telomeres length in 66 women with fibromyalgia with 22 healthy female controls. Subjects completed psychosocial questionnaires including the Brief Pain Inventory (BPI; 0-10 scale) and the Center for Epidemiologic Studies Depression Scale (CESD). Blood samples were collected and telomere length was measured. Although patients had shorter telomere length than controls, the difference was not statistically significant. However, higher levels of pain within fibromyalgia were associated with shorter telomere length.
In quantitative sensory testing, the researchers found a “very high correlation” between telomere length and sensitivity to pain that was statistically significant. “People with the shortest telomere lengths were by far the most sensitive to pain,” Dr. Hassett said.
Clinical pain, depression, and telomere length
To assess the associations between telomere length and clinical pain and depression, partial correlations controlling for age were conducted for all ﬁbromyalgia patients with data available.
The difference in telomere length between higher pain and lower pain groups was estimated at 193 base pairs (age adjusted). However, the combined effects of depressive symptoms and pain severity revealed a signiﬁcant relationship with telomere length. Analysis of the effects of the 4 pain/depression subgroups, controlling for age, showed a signiﬁcant difference between the low-pain/low-depression and the high-pain/high-depression groups.
When pain and depression were combined, patients categorized as high-pain/high-depression had an age-adjusted telomere length 265 base pairs shorter than those with low-pain/low-depression, a difference consistent with approximately 6 years of chronological aging.
Chronic pain, stress, and telomere length
Researchers at the University of Florida found that shortened telomere length was related to chronic pain and stress. They analyzed blood samples in 36 older adults, half of whom reported no chronic pain and the other half had chronic knee osteoarthritis pain. Subjects completed a physical exam, radiographs, health history, and psychosocial questionnaires.
Four groups were identified characterized by pain status and the Perceived Stress Scale scores: 1) no pain/low stress, 2) no pain/high stress, chronic pain/low stress, and 4) chronic pain/high stress.
Specifically, the chronic pain/high stress group had significantly shorter telomere length compared to the no pain/low stress group. Age was negatively correlated with telomere length, particularly in the chronic pain/high stress group.
These findings provide evidence that chronic pain and psychosocial stress may impose a “burden on the system,” accelerating cellular aging.