Brain functional connectivity and morphology changes in medication-overuse headache: Clue for dependence-related processes?

Abstract

Background: Several imaging studies have identified localized anatomical and functional brain changes in medicationoveruse headache (MOH). Objective: The objective of this article is to evaluate whole-brain functional connectivity at rest together with voxel-based morphometry in MOH patients, in comparison with episodic migraine (EM) patients and healthy controls (HCs). Methods: Anatomical MRI and resting-state functional MRI scans were obtained in MOH patients (n ¼ 17 and 9, respectively), EM patients (n ¼ 18 and 15, respectively) and HCs (n ¼ 17 and 17). SPM8 was used to analyze voxel-based morphometry and seed (left precuneus) to voxel connectivity data in the whole brain. Results: Functional connectivity at rest was altered in MOH patients. Connectivity was decreased between precuneus and regions of the default-mode network (frontal and parietal cortices), but increased between precuneus and hippocampal/ temporal areas. These functional modifications were not accompanied by significant gross morphological changes. Furthermore, connectivity between precuneus and frontal areas in MOH was negatively correlated with migraine duration and positively correlated with self-evaluation of medication dependence. Gray matter volumes of frontal regions, precuneus and hippocampus were also negatively related to migraine duration. Functional connectivity within the defaultmode network appeared to predict anxiety scores of MOH patients while gray matter volumes in this network predicted their depression scores. Conclusions: Our data suggest that MOH is associated with functional alterations within intrinsic brain networks rather than with macrostructural changes. They also support the view that dependence-related processes might play a prominent role in its development and maintenance.

Resting-state fMRI functional connectivity: a new perspective to evaluate pain modulation in migraine?

“…This particular group of patients showed an altered RS FC in the DMN as well as an increased connectivity between the precuneus and hippocampal temporal areas, which did not have corresponding structural abnormalities. The authors stated that alterations in pain-processing networks might be due to long-lasting pain processes, whereas alterations in DMN could be related to addiction processes [34]. The impaired FC might precede alteration in brain areas morphology.…”

Diagnosis, pathophysiology and management of chronic migraine: a proposal of the Belgian Headache Society

“…metabolism/activation of lateral pain system [50,135] %% cortical sensitivity depending on drug overused [49] precuneus connectivity: ! with DMN, % with hippocampus [51] % tissue density in PAG [48] Acta Neurol Belg…”

“…In MOH, sensory cortices become markedly sensitized depending on the drugs overused [49], the orbitofrontal cortex is hypometabolic [50] and atrophic [48], and connectivity of the precuneus is decreased with the default mode network, but increased with the hippocampus [51].…”

Pain modulation is affected differently in medication-overuse headache and chronic myofascial pain – A multimodal MRI study

“…spatially distinct areas of the brain that show synchronous BOLD signal fluctuations at rest, have been consistently identified using various methodological approaches (14,15), including the default-mode network (DMN), fronto-parietal attention network (FPN), sensorimotor network (SMN), or saliency network (SN), which comprises the bilateral insulae and dorsal anterior cingulate cortex (ACC). One study has examined RS FC in MOH and reported decreased FC between the precuneus and fronto-parietal regions within the DMN and increased FC between precuneus and hippocampal/temporal areas (16). Increased FC between the PAG and both nociceptive and somatosensory regions was found in patients with episodic migraine between the attacks (17).…”