Fibromyalgia (FM) is a chronic pain condition that affects many people. Scientists have been trialing the link between FM and dysautonomia, an imbalance in the autonomic nervous system. They conducted a clinical trial using heart rate variability (HRV) analysis to understand this connection better.
In the trial, researchers compared 51 female FM patients aged 18 to 65 years with 31 healthy female participants of the same age. The participants underwent a 20-minute experiment that involved alternating relaxation and cognitive stress tasks, like solving math problems. The scientists recorded their heart rates and measured their heart's electrical activity using electrocardiograms.
The researchers analyzed several HRV measures to find out how FM and dysautonomia are related. These measures included heart rate (HR), the average time between heartbeats, the difference between successive heartbeats, and the variation in intervals between normal heartbeats.
The trial revealed some important differences between FM patients and healthy participants. The FM patients had higher baseline heart rates than the healthy group, meaning their hearts beat faster even at rest. Additionally, their average time between heartbeats was shorter compared to the healthy participants.
When the participants faced cognitive stress (doing math problems), the FM patients showed a smaller increase in heart rate compared to the healthy participants. They also had a smaller decrease in the average time between heartbeats during stressful tasks.
Different Types of FM Patients
To understand the connection between dysautonomia and FM symptoms, the researchers divided the FM patients into three groups based on their HRV reactivity.