Glucose as an adjuvant of exposure treatment in participants with public speaking anxiety (PSA)

Status

Recruiting

Phases

Unknown

Study type

Interventional

Source

DRKS

Registry ID

DRKS00039069

Enrollment

Registered

2026-01-23

Start date

2025-04-01

Completion date

Unknown

Last updated

2026-02-02

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Participants with Public Speaking Anxiety, with or without Social Anxiety Disorder

Interventions

Group 1: 25g of glucose in 300 ml of water, administered once on each experimental day Group 2: Placebo: 30 mg saccharin in 300 ml of water, administered once on each experimental day

Eligibility

Sex/Gender

All

Age

18 Years to No maximum

Inclusion criteria

Inclusion criteria: - Fluent in German - Affected by public speaking anxiety (as measured by screening questions) - Currently healthy - Body-Mass-Index (BMI) between 18.5-26 for women and 19-27 for men

Exclusion criteria

Exclusion criteria: - Diabetes and other chronic diseases (only selfreport) - Drug or medication intake within the last 6 months, except for occasional use of pain killers and hormonal contraceptives - Individuals with a history of mental illness are excluded from participating in the study. Individuals who meet the criteria for social anxiety disorder are eligible to participate - Heart or respiratory diseases - Neurological problems - Current pregnancy

Design outcomes

Primary

Measure	Time frame
To assess PSA severity, participants are required to complete the 34-item Personal Report of Public Speaking Anxiety (PRPSA; McCroskey, 1970) on each experimental day. To assess fear during the experiment, the single-item Subjective Units of Distress Scale (SUDS) is used. Participants with a history of psychological disorders will be excluded from the study. However, individuals meeting criteria for social anxiety disorder (SAD) will be eligible for inclusion. SAD will be measured using the self-report Social Phobia Inventory (SPIN), Social Phobia Scale (SPS) and Social Interaction Anxiety Scale (SIAS) subtests from the Scales for Social Anxiety Disorder (SOZAS) (von Consbruch et al., 2016). Physiological activity during the experiment will be recorded using a wireless BioSignalsPlux Explorer portable device at a sampling rate of 1000 Hz. Skin conductance (SC) and heart rate (HR) are recorded throughout all sessions as measures of fear arousal. SC is measured using two electrodes attached to the proximal area of the subject’s non-dominant palm. HR is recorded by electrocardiography (ECG) acquired with a single-lead differential bipolar ECG sensor connected to three 24 mm disposable Ag–AgCl electrodes. Electrode placement is equivalent to standard medical-grade V6 lead.	—

Measure

Time frame

To assess PSA severity, participants are required to complete the 34-item Personal Report of Public Speaking Anxiety (PRPSA; McCroskey, 1970) on each experimental day. To assess fear during the experiment, the single-item Subjective Units of Distress Scale (SUDS) is used. Participants with a history of psychological disorders will be excluded from the study. However, individuals meeting criteria for social anxiety disorder (SAD) will be eligible for inclusion. SAD will be measured using the self-report Social Phobia Inventory (SPIN), Social Phobia Scale (SPS) and Social Interaction Anxiety Scale (SIAS) subtests from the Scales for Social Anxiety Disorder (SOZAS) (von Consbruch et al., 2016). Physiological activity during the experiment will be recorded using a wireless BioSignalsPlux Explorer portable device at a sampling rate of 1000 Hz. Skin conductance (SC) and heart rate (HR) are recorded throughout all sessions as measures of fear arousal. SC is measured using two electrodes attached to the proximal area of the subject’s non-dominant palm. HR is recorded by electrocardiography (ECG) acquired with a single-lead differential bipolar ECG sensor connected to three 24 mm disposable Ag–AgCl electrodes. Electrode placement is equivalent to standard medical-grade V6 lead.

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Secondary

Measure	Time frame
Secondary dependent variables (Since this project involves contributions from students participating in coursework and writing Bachelor’s and Master’s theses, some additional measures have been included to meet these educational requirements. These are not part of the study's primary objectives): • A measure of threat expectancy change will be added at different points of the experiment following Pittig and colleagues (2022): Definition of individual threat at Session 1; threat expectancy rating before exposure (sessions 1 and 2); threat occurrence; maximum of fear and adjusted threat expectancy after exposure (sessions 1 and 2). • Based on evidence that cortisol levels influence exposure effects (Lass-Hennemann & Michael, 2014) and the close connection between cortisol and glucose in metabolism regulation and the stress response (Ferreira de Sá et al., 2014; Glenn et al., 2014; Von Dawans et al., 2021), saliva cortisol samples will be collected at the beginning of each session (Sessions 1-3), immediately after each BAT, and at the end of each exposure. • Following Cheng and colleagues (2017) on the discrepancy between self-rated and objective ratings of speech performance and its decline throughout exposure, speech performance will be collected as well. A German translation of the Experimenter’s Perception of Speech Performance (ESPS) and the Modified Perception of Speech Performance (MPSP; Cody & Teachman, 2011), which were adapted from the speech performance Rating from Rapee & Lim (1992), will be used. Speech performance will be assessed both through self-ratings, and observer ratings provided by the confederates, measured at the end of sessions 1 and 2.	—

Measure

Time frame

Secondary dependent variables (Since this project involves contributions from students participating in coursework and writing Bachelor’s and Master’s theses, some additional measures have been included to meet these educational requirements. These are not part of the study's primary objectives): • A measure of threat expectancy change will be added at different points of the experiment following Pittig and colleagues (2022): Definition of individual threat at Session 1; threat expectancy rating before exposure (sessions 1 and 2); threat occurrence; maximum of fear and adjusted threat expectancy after exposure (sessions 1 and 2). • Based on evidence that cortisol levels influence exposure effects (Lass-Hennemann & Michael, 2014) and the close connection between cortisol and glucose in metabolism regulation and the stress response (Ferreira de Sá et al., 2014; Glenn et al., 2014; Von Dawans et al., 2021), saliva cortisol samples will be collected at the beginning of each session (Sessions 1-3), immediately after each BAT, and at the end of each exposure. • Following Cheng and colleagues (2017) on the discrepancy between self-rated and objective ratings of speech performance and its decline throughout exposure, speech performance will be collected as well. A German translation of the Experimenter’s Perception of Speech Performance (ESPS) and the Modified Perception of Speech Performance (MPSP; Cody & Teachman, 2011), which were adapted from the speech performance Rating from Rapee & Lim (1992), will be used. Speech performance will be assessed both through self-ratings, and observer ratings provided by the confederates, measured at the end of sessions 1 and 2.

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Countries

Germany

Contacts

Public ContactDiana S. Ferreira de Sá

Universität des Saarlandes Klinische Psychologie und Psychotherapie

diana.ferreira@uni-saarland.de+49 68130271209

Outcome results

None listed

Source: DRKS (via WHO ICTRP) · Data processed: Feb 7, 2026