Exposure to anesthetic gases and Parkinson’s disease: a case report

Abstract

BackgroundThe administration of anesthetics determines depression of the central nervous system and general anesthesia by inhalation may cause an environmental pollution of the operating rooms. It may therefore conceive a possible occupational etiology of Parkinson's Disease (PD).Case presentationIn a Caucasian male aged 59 years, PD was diagnosed by brain scans with a presynaptic radioactive tracer of the dopaminergic system. Family history was negative for Parkinson’s disease or essential tremor. He was a smoker, a moderate consumer of coffee and alcohol, and never exposed to pesticides/metals. For 30 years (since the age of 29 until today), he worked as an anesthesiologist in private clinics in the Veneto (Northern Italy), exposed to anesthetic gases. The time elapsed from first exposure to onset of disease is 22 years, fulfilling the requirement of the induction/latency period. A literature search demonstrated unacceptable levels of anesthetic gases in public hospitals of the Veneto region from 1990 to 1999. This exposure was presumably high also in private hospitals of the region until at least 2007, when an overexposure to sevoflurane was repeatedly measured in this patient. The association between occupational exposure to anesthetic gases and risk of Parkinson’s disease was supported by a case-control study (reporting a two-fold increase in the risk of PD associated with a clinical history of general anesthesia) and a cohort study comparing mortality from PD between US anesthesiologists and internists (showing a statistically significant excess (p=0.01) in anesthesiologists compared to internists). Numerous recent mechanistic studies (in vitro essays and in vivo short-term studies) strengthened the association between exposure to anesthetic gases (nitrous oxide, halothane, isoflurane, levoflurane) and PD.ConclusionIn view of the limited evidence of human studies and the sufficient evidence of experimental studies, the high exposure to anesthetic gases could have induced PD in the subject under study.

Inhalational Anesthetics Induce Neuronal Protein Aggregation and Affect ER Trafficking

“…tau hyperphosphorylation) 10 , 11 , 13 , 15 , 16 and induce the aggregation of disease-related proteins (i.e. amyloid and huntington protein) 13 , 15 , 16 , 20 but causal studies in patients have more mixed results 3 , 6 , 7 , 18 , 45 .…”

Neuroprotective Effects against POCD by Photobiomodulation: Evidence from Assembly/Disassembly of the Cytoskeleton

“…86 On the other hand, exposure of presymptomatic AD mice to anesthetics (halothane, isoflurane) did not accelerate the progression of the disease but, on the contrary, appeared to result in the preconditioning against neurodegeneration, due to increased phosphorylation of tau. 87 Despite anecdotal and some epidemiological evidence of a link between anesthetics and AD, 88 PD, [89][90][91] and POCD, 92 clinical evidence does not, on the whole, support the animal studies. Large studies such as the ISPOCD 93 as well as metaanalyses 94,95 have found no link between anesthetics and POCD or AD, including comparisons between general and regional anesthetics.…”

Frequency of previous head trauma and surgery with general anesthesia in parkinson’s disease and essential tremor

“…Halothane and isoflurane increase cytotoxicity by increasing oligomerization of beta-amyloid. The same mechanism presents itself at the nigro-striatal level, producing dopaminergic neurotoxicity (13).…”

“…Occupational exposure to anesthetic gases may cause a two-fold increase in the risk of PD. A study comparing mortality from PD showed a statistically significant predominance in anesthesiologists compared to internists (13).…”