Medication-overuse headache (MOH) is a chronic disorder associated with overuse of
analgesic drugs,
triptans, non-steroidal anti-inflammatory drugs (
NSAIDs) or other acute
headache compounds. Various epidemiologic investigations proved that different drug types could cause nephrotoxicity, particularly in chronic patients. The aim of the present work was to analyze, by a proteomic approach, the urinary
protein profiles of MOH patients focusing on daily use of
NSAIDs, mixtures and
triptans that could reasonably be related to potential renal damage. We selected 43 MOH patients overusing
triptans (n = 18),
NSAIDs (n = 11), and mixtures (n = 14), for 2-30 years with a mean daily
analgesic intake of 1.5 ± 0.9 doses, and a control group composed of 16 healthy volunteers. Urine
proteins were analyzed by mono-dimensional gel electrophoresis and identified by mass spectrometry analysis. Comparing the proteomic profiles of patients and controls, we found a significantly different
protein expression, especially in the
NSAIDs group, in which seven
proteins resulted over-secreted from kidney (OR = 49, 95% CI 2.53-948.67 vs. controls; OR = 11.6, 95% CI 0.92-147.57 vs.
triptans and mixtures groups). Six of these
proteins (
uromodulin, α-1-microglobulin,
zinc-α-2-
glycoprotein,
cystatin C, Ig-kappa-chain, and inter-α-
trypsin heavy chain H4) were strongly correlated with various forms of kidney disorders. Otherwise, in mixtures and in
triptans abusers, only three
proteins were potentially associated to pathological conditions (OR = 4.2, 95% CI 0.33-53.12, vs. controls). In conclusion, this preliminary proteomic study allowed us to define the urinary
protein pattern of MOH patients that is related to the abused drug. According with the obtained results, we believe that the risk of nephrotoxicity should be considered particularly in MOH patients who abuse of
NSAIDs.