Anton Glans1,2, Jonna Wilén2, Lenita Lindgren1, Isabella M. Björkman-Burtscher3,4, and Boel Hansson5,6
1Department of Nursing, Umeå University, Umeå, Sweden, 2Department of Radiation Sciences, Radiation Physics, Umeå University, Umeå, Sweden, 3Department of Radiology, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden, 4Department of Radiology, Sahlgrenska University Hospital, Gothenburg, Sweden, 5Department of Medical Imaging and Physiology, Skåne University Hospital, Lund, Sweden, 6Department of Diagnostic Radiology, Clinical Sciences, Lund University, Lund, Sweden
Synopsis
Our aim was
to explore the prevalence of
health complaints subjectively associated with static magnetic field and
acoustic noise exposure among MR personnel in Sweden, using CT personnel as a
control group. Utilizing a cross-sectional survey, 529 respondents answered
items regarding symptom prevalence and its attribution, acoustic noise at work,
health factors and work-environmental details including stress. Respondents
were categorized into three groups (MR personnel, CT personnel, and mixed
personnel (both MR and CT)) and data were tested with logistic regression to
evaluate risk associations with symptoms.
Introduction
MR personnel encounter both strong static magnetic fields (SMFs) and loud acoustic noise at work. Exposure to these sources is associated with adverse health effects, and transient symptoms such as vertigo, tiredness, metallic taste, headache, nystagmus, head ringing, visual light flashes, nausea, and having difficulties concentrating have been reported (1-6). However, these symptoms could be influenced by other work-environmental factors, such as stress (7, 8).
We propose to compare symptom prevalence and attribution among MR personnel with a similar group working without exposure to strong SMFs – i.e., CT personnel, and adjust for work-related confounders to better understand the contributing factors in the working environment that can cause harm.Methods
To assess health complaints, a cross-sectional survey was sent to the hospitals with MR units in Sweden between September 2015 and April 2016. Personnel working at any degree with MR and/or CT at the sites were considered eligible for participation. Out of 543 respondents, 529 were included in the study.
In addition to demographic data, related medical history, and work-environmental details (e.g., psychosocial workload and stress), the survey asked respondents to rate prevalence of symptoms subjectively associated with SMF and acoustic noise during the last year. Outcomes were dichotomized into never/seldom (<1 time/week) or often (≥1 time(s)/week). Moreover, respondents were asked whether they attributed symptoms to being in the MR and/or CT scanner room, and if so, did symptoms occur in relation to the position in the room or any body movement. Survey items also covered environmental noise factors and self-rated hearing function.
Survey data was looked at in either of two ways. In one test series, all 529 eligible subjects were included to test the association between the amount of weekly working MR hours and symptom prevalence. All other data analysis was based on subjects (n = 342) categorized into three separate groups by setting a cut-off value of 20 working hours/week within the respective image modalities, or a combination thereof: MR personnel not working with CT (n = 121), CT personnel not working with MR (n = 75), or mixed personnel working with both MR and CT (n = 146).
We used descriptive statistics to explore demographic data. Logistic regression was used to test associations between sex, age, stress, SMF strength, MR working hours, and symptom prevalence. Outcomes are described in 95% confidence intervals (CI) and odds ratios (OR), where values >1 denote the increased risk factored. A p-value of ≤0.05 was considered statistically significant in all tests.Results
No significant differences in symptom prevalence were seen between CT, MR or mixed personnel. However, working at ≥3 T increased SMF-associated symptoms (vertigo, nausea, metallic taste, and/or illusion of movement) as compared with working at ≤1.5 T (OR: 2.03, 95%CI: 1.05-3.93, p = 0.04). The CT group showed 2.6 times higher odds of experiencing acoustic noise at work in general as troublesome to “a great deal” than the MR group (p <0.01) but no significant differences were seen between self-rated hearing function (p >0.05) or established hearing loss (p >0.05).
The amount of MR working hours/week showed no significant differences (all p > 0.05) in symptom prevalence among all 529 eligible participants. However, stress had a significant positive association with all symptom variables individually (all p <0.05) except for metallic taste (p = 0.18). Additionally, for each year of age, the odds of experiencing ringing sensations (tinnitus) one or more times a week increased by 3% (OR: 1.03; 95%CI: 1.00-1.06, p = 0.04). For unusual drowsiness, each year of life decreased the odds by 2.8% (OR: 0.97; 95%CI: 0.95-0.99, p = 0.01). Female sex increased the odds of headache 3.5-fold (OR: 3.47; 95%CI: 1.32-9.08, p = 0.01), while each year of life decreased odds of headache by 3.7% (OR: 0.96; 95%CI: 0.94-0.99, p <0.01). For sleeping difficulties, each year of life increased the odds by 3.1% (OR: 1.03; 95%CI: 1.01-1.05, p <0.01).Conclusion
No differences in adverse symptom prevalence were seen between MR and CT personnel. Notably, associated symptoms were more influenced by stress than by actually working with MRI. Acoustic noise at work was rated as more troublesome by CT than MR personnel. Our findings might reflect a positive effect of MR environmental safety advancements, such as stray field shielding and sound proofing, whereas CT environments might have been foreshadowed in similar related aspects outside of radiation safety.Acknowledgements
No acknowledgement found.References
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