SLE Patients at Greater Risk for Vocal Disorders, Brazilian Study Reports
Many systemic lupus erythematous (SLE) patients suffer from vocal disorder, or dysphonia, and should get voice therapy to improve the overall quality of their lives.
So argues an article, “Voice disorder in systemic lupus erythematosus,” that recently appeared in the open-access journal PLOS One.
Back in the 1950s, people with SLE had only a 50 percent chance of surviving within five years of diagnosis. Today, survival rates are at 99 percent, yet SLE patients may suffer from dysphonia due to progressive tissue damage, a group of Brazilian researches hypothesized.
Using both objective and subjective measures, the authors tested their hypothesis, selecting 36 SLE women between 17 and 56 years old being treated at two hospitals in the northeastern Brazilian city of Belém. As controls, the study included 32 age- and gender-matched controls with no previous complaints of dysphonia. None of the subjects had any gross abnormalities of the vocal folds, nor were they smokers or heavy drinkers.
After obtaining vocal recordings as a direct physical measurement of vocal quality, they assessed the following objective measures of voice quality: fundamental frequency (F0), intensity, jitter (index of F0 variability), shimmer (index of intensity variability) and harmonics-to-noise ratio (HNR; index of glottal turbulence noise and hoarseness).
Additionally, the researchers used a highly validated tool for perceptual voice quality, the GRBAS (Grade, Roughness, Breathiness, Asthenia, Strain) scale. This tool measures a subject’s general grade of dysphonia (G) by quantifying four subjective parameters: roughness (R), breathiness (B), asthenia, or lack of energy (A), and strain (S).
Control subjects showed standard features. However, vocal signals from patients with SLE showed several deficits, including reduced amplitude and high variability. Additionally, compared to controls, SLE patients had lower vocal intensity and HNR, increased jitter and shimmer, and higher scores for all the components of the GRBAS scales. These results indicate an impaired vocal performance.
Importantly, when asked in a questionnaire about their vocal parameters,29 out of 36 women said they suffered from at least one perceived vocal deficit, such as fatigue (19 of 36) or hoarseness (17of 36). This correlation between objective and subjective perceptions of vocal quality is important. Since patients perceive a reduction in vocal quality, this is a strong indication that SLE-related dysphonia may have direct psychological effects that reduce patients’ quality of life.
Finally, researchers assessed clinical tissue damage using the SLICC/ACR damage scores between specific organ systems and vocal parameters. Their results suggest that SLE-related dysphonia is most likely multifactorial and cannot be attributed to one organ system, although they recorded the highest correlations with pulmonary, gastrointestinal and musculoskeletal systems.
However, the study’s small sample size limits researchers’ ability to fully understand how specific tissue damage relates to vocal quality.
“We tentatively conclude that including vocal evaluations and voice therapy in the guidelines for anamnesis [patient account of medical history] and long-term care of SLE may potentially improve patient life quality and reduce disease burden,” the authors wrote.