EFFECTS OF WATER RESISTANCE THERAPY ON VOCAL ECONOMY IN INDIVIDUALS WITH PARKINSON’S DISEASE – PRELIMINARY RESULTS

Objective: Analyze the effects of vocal therapy with resonance tubes immersed in water phonation technique on the vocal economy of individuals with Parkinson’s Disease (PD).

Methods: This study involved 5 individuals with PD (4 men and 1 woman), aged between 59 and 68 years (mean: 63.2 years). Participants included individuals who were maintaining a stable condition with medication, aged over 50 years old, and scoring above 21 on the Montreal Cognitive Assessment. The water resistance therapy was performed using a resonance tube (glass, 27cm x 9mm), with the tube depth in water ranging from 2cm to 9cm, increasing in difficulty as the exercises progressed. Participants underwent eight 45-minute sessions of voice therapy, twice a week, across a four-week period. The Quasi Output Cost Ratio (QOCR) formula was applied to calculate vocal economy, defined as QOCR = (NPS/CCegg) x (T/T0), where NPS = sound pressure level (dB); CCegg = glottic contact coefficient, calculated as the ratio of the closed phase over the entire waveform cycle (%); T is the value equivalent to the duration of a glottic cycle, and T0 corresponds to the average duration of the glottic cycle, a value inversely related to the average fundamental frequency (f0) during speech, established for women (0.005 seconds) and men (0.001 seconds). A higher QOCR value indicates greater vocal economy.

Results: The variables NPS, Fo, CCegg, and QOCR exhibited a parametric distribution. The statistical analysis was performed using the Statistica software, applying the paired T-test (significance level=0.05). It was observed that for the QOCR measures (p=0.032) and CCegg (p=0.010), there was a statistically significant difference after the intervention.

Conclusions: In conclusion, it can be inferred that vocal therapy with water resistance resulted in an increase in vocal economy in individuals with Parkinson’s Disease, primarily by reducing the glottic contact coefficient, which is associated with glottic impact stress. It is suggested to expand the sample size to further complement the analysis.