Pain comes in two flavors.
The acute version tells us to snatch a hand away from a hot flame. On the same hand, chronic pain would last interminably; our neurochemical pathways perceive that heat long after the fire dies.
Chronic pain is frustratingly difficult to treat. Pain and perception of pain are actively managed in what is called neuroplasticity. Our microbes are involved. Gut bacteria regulate multiple neurochemical and neuro-metabolic pathways via the gut-brain axis.
When they are disturbed as in dysbiosis, pain management may suffer. Pathogenic bacteria may affect pain perception in a maladaptive way.
A new way to look at constipation
Some studies showed that stool consistency and constipation are associated with gut microbiome composition and dysbiosis.
Compared with controls, the subjects with constipation in one study showed reduced abundance in Prevotella and increased in several genera of Firmicutes, compared with controls. Another revealed fewer Lactobacillus and Bifidobacteria species in the stool of adults with chronic constipation.
Constipation and chronic pain
One new study looked at the relationship between constipation or usual stool form and pain severity of patients with chronic pain. The Association Between Constipation or Stool Consistency and Pain Severity in Patients With Chronic Pain appeared in Anesthesiology and Pain Medicine journal.
The study at Aichi Medical University in Japan was conducted on 365 patients presenting with chronic pain of the entire body or at various locations.
Results
Constipation was linked with the pain severity of all the patients and also patients with low back and/or lower limb pain, whole body.
Mechanism of action
Gut microbes manage pain perception pathways via hypypothalamic-pituitary-adrenal axis, chemokines and cytokines, and autonomic nervous and enteric nervous systems, what is called the aforementioned gut-brain axis.
These microbes can also release neuroactive molecules and increase gut-blood barrier and blood-brain barrier permeability. One of these in particular called 5-HT assists in regulation of pain perception.
Takeaway
The dysbiosis of constipation may disrupt pain management systems, thereby aggravating pain intensity of patients with chronic pain.
Eat more fiber!