Clinical validation of the self-reported Glasgow Antipsychotic Side-effect Scale using the clinician-rated UKU side-effect scale as gold standard reference

Abstract

Background: Antipsychotics are key for the treatment of psychotic and several non-psychotic disorders. Unfortunately, antipsychotic medications are associated with side effects, which may reduce quality of life and treatment adherence. Therefore, regular screening of antipsychotic side effects is essential. The Glasgow Antipsychotic Side-effect Scale is a patient self-report scale developed for this purpose. However, the Glasgow Antipsychotic Side-effect Scale has only been validated against another self-report side effect measure, which is suboptimal. Objective: We aimed to validate the Glasgow Antipsychotic Side-effect Scale using the clinician-rated Udvalg for Kliniske Undersøgelser side-effect rating scale as the gold standard reference. Results: 81 antipsychotic-treated outpatients with schizophrenia-spectrum disorders (age = 42±13 years; males = 43%, schizophrenia = 77%, illness duration: median = 11 years) completed the Glasgow Antipsychotic Side-effect Scale and were subsequently scored on the Udvalg for Kliniske Undersøgelser by trained raters. Sensitivity, specificity, positive predictive value and negative predictive value were calculated for paired Glasgow Antipsychotic Side-effect Scale and Udvalg for Kliniske Undersøgelser items. Sensitivity of Glasgow Antipsychotic Side-effect Scale items ranged from 33–96%, with 19 (86%) having >75% sensitivity. Lowest sensitivity emerged for “nocturnal enuresis” (33%), “galactorrhea” (50%) and “hyperkinesia” 14–99%, with 14 items (64%) having >75% specificity, being lowest for “asthenia” (14%), “polyuria/polydipsia” (35%), “sedation” (41%), “akathisia” (53%), “dystonia” (65%), “hyperkinesia” (68%), “hypokinesia” (70%) and “accommodation” (70%). Positive predictive value ranged from 7–85%, with six items (27%) having a positive predictive value >75%. Negative predictive value ranged from 40–98%, with 21 items (95%) having a negative predictive value >75%. The mean time to complete the Glasgow Antipsychotic Side-effect Scale was 4±2 minutes. Conclusion: The Glasgow Antipsychotic Side-effect Scale demonstrated satisfactory validity as a self-rated tool for antipsychotic side effects and may aid measurement-based care and decision-making.

Reducing risks associated with medicines and lifestyle in a residential care population with intellectual disabilities: evaluation of a pharmacy review initiative in England

“…The pharmacists assessed residents’ antipsychotic medicines using the GASS 19 and two of the residents reported a score of 22–42 (moderate side effects), while 89 residents reported a score under 21 (absent/mild side effects). None of the residents reported a score of 43–63 (severe side effects).…”

Clinical validation of the Aarhus Side effect Assessment Questionnaire(ASAQ)

“…Such a questionnaire would enable frequent and systematic screening for side effects that could be followed up by targeted side effect assessments by clinicians informed by the patients’ self-report and supplemented with relevant paraclinical tests, for example, electrocardiogram to screen for QTc prolongation. This objective, along with its underlying rationale, stems from our findings from the analogue clinical validation study of the GASS (Waddell and Taylor, 2008) among outpatients with psychotic disorders (Schouby Bock et al, 2020). In that study, we found that 48% of the participants had side effects according to the UKU that were not covered by the GASS (Schouby Bock et al, 2020), likely due to the fact that the GASS only covers 26 of the 48 UKU items.…”

“…This objective, along with its underlying rationale, stems from our findings from the analogue clinical validation study of the GASS (Waddell and Taylor, 2008) among outpatients with psychotic disorders (Schouby Bock et al, 2020). In that study, we found that 48% of the participants had side effects according to the UKU that were not covered by the GASS (Schouby Bock et al, 2020), likely due to the fact that the GASS only covers 26 of the 48 UKU items. Consequently, it fails to adequately assess psychiatric/cognitive (depression, concentration difficulties, failing memory, tension, sleep disturbances, emotional indifference, and increased dream activity), autonomic (diarrhea, constipation, and increased tendency to sweating), cutaneous (rash, pruritus, photosensitivity, and increased pigmentation), neurological (rigidity, epileptic seizures, and paresthesia), and other (headache, weight loss, and psychic and physical dependence) side effect domains.…”

“…The ASAQ was developed based on (1) results from our clinical validation of the Glasgow Antipsychotic Side-Effect Scale (GASS) (Schouby Bock et al, 2020), (2) a review of the literature concerning scales assessing side effects of psychotropic medication and electroconvulsive therapy (ECT), (3) information from the Neuroscience-based Nomenclature database regarding frequent and clinically relevant psychotropic side effects (Zohar et al, 2015), and (4) pharmacovigilance reports (https://pro.medicin.dk) for commonly prescribed psychotropic medications. In addition to covering all items from the clinician-rated UKU (except for psychic and physical dependence), the ASAQ contains items assessing urinary incontinence, female gynecomastia, visual disturbances, abdominal pain, flatulence and increased/reduced appetite.…”

Validity of the Aktibipo Self-rating Questionnaire for the Digital Self-assessment of Mood and Relapse Detection in Patients With Bipolar Disorder: Instrument Validation Study

“…The World Health Organization has identified BD as one of the most frequent causes of disability in youth [2]. The existing literature suggests that measurement-based care may be an effective clinical strategy in most psychiatric disorders [3][4][5][6], and monitoring of the clinical course of BD is therefore of high clinical and research interest. Several organizations, such as the International Society for Bipolar Disorders, have recommended the implementation of measurement-based care in the treatment of BD [7].…”