The common symptom of fatigue experienced by multiple sclerosis (MS) patients may be caused by regional damage in the brain, according to research conducted at the Vita-Salute San Raffaele University in Italy and published in the journal Radiology. Scientists analyzed atrophies and lesions in the white matter and grey matter of 65 MS patients to conclude that both parameters were linked.
“Damage to strategic brain white matter and grey matter regions, in terms of micro structural abnormalities and atrophy, contributes to pathogenesis of fatigue in MS, whereas global lesional, white matter, and grey matter damage does not seem to have a role,” explained the researchers, as quoted in an article on HCPLive by Rachel Lutz, entitled, “Fatigue in Multiple Sclerosis Could be Pinpointed to Brain Region.” “This study supports the use of multimodal magnetic resonance imaging and regional analysis to assess fatigue in patients with MS.”
The study included 31 MS patients who experienced fatigue and 32 who didn’t experience it, as well as 35 other patients who functioned as a control group. All participants were examined through dual-echo, double inversion recovery, high-resolution T1-weighted and diffusion-tensor magnetic resonance imaging (MRI), and researchers were able to measure the degree of atrophy, as well as compare the damage, the normal-appearing white matter, and they grey matter of the different groups.
The group of fatigued patients presented greater differences in specific regions of the brain, in comparison with the non-fatigued group. However, all of the patients with MS showed more brain damage in both the grey and the white matter compared to the control group.
Researchers analyzed the right nucleus accumbens, right inferior temporal gyrus, and left frontal gyrus of the fatigued patients using a Fatigue Severity Scale, and discovered that those were the regions connected to fatigue, since those were the locations were fatigued patients had more lesions. Scientists were also able to predict fatigue in the patients by using the right inferior temporal gyrus and the right anterior thalamic radiation damage.
“Lesional, atrophy, and DT MR measures of global damage to brain, white matter, and GM did not differ between fatigued and nonfatigued patients. Compared with nonfatigued patients and control subjects, fatigued patients experienced atrophy of the right side of the accumbens, right inferior temporal gyrus, left superior frontal gyrus, and forceps major. They also had lower fractional anisotropy of forceps major, left inferior fronto-occipital fasciculus, and right anterior thalamic radiation,” said the authors.
The research team is now planning to continue the trials with a longitudinal study to assess the limitations of their conclusions, while using MRIs to define a pathogenetic link between atrophy and fatigue severity. This study may have an impact on the treatment of fatigue in MS patients, which occurs in about 80% of the patients, according to the National MS Society.
Fatigue as a symptom of MS can be severe, as it happens daily and regardless the level of rest or sleep, a symptom known as lassitude. It is worsened by factors such as heat or humidity, and inhibits MS patients from performing daily activities. Some people even have difficulties with simple tasks like dressing, bathing, or cooking.