(T0930-01-05) Acceptable Solid Oral Dosage Forms for Older Adults as Prerequisite for Medication Adherence – The Current Situation

Purpose: Older adults are often confronted with multimorbidity and thus are subject to polypharmacy. Adequate patient acceptability is a prerequisite for patients’ adherence to their pharmacotherapy and needs to be considered in the development of patient-centric drug products. Besides the characteristics of the patient, those of the drug product have to be taken into account. The size and shape of solid oral dosage forms play a crucial role for the swallowability, visual perception, as well as any handling that needs to be conducted prior to medication administration. We assessed appropriate sizes and shapes of tablets for older adults and compared them to the most commonly prescribed drug products for this patient population in order to see whether adequate dosage forms are provided to the main group of medication end users.

Methods: A randomized intervention study was conducted which comprised a deglutition part assessing participants’ swallowing capabilities (well, moderately, or not swallowable). Further, the anticipated swallowability according to visual perception was tested by presenting a range of dosage forms in showcases (swallowable or not swallowable). The third study part was focused on the handling assessment (well, moderately, or not to handle). The cut-off value for the evaluation of swallowability, visual perception, and handling was set to 80.0%. Sizes and shapes of the tested tablets are shown in Table 1. In order to create a representative comparison of tablet sizes and shapes used in older adults, we researched the 300 drug products being most frequently prescribed by independent physicians to outpatients, 65 years and older. These drug products were dispensed by public or hospital pharmacies to the account of statutory health insurances in Germany (data source: GKV-Arzneimittelindex im Wissenschaftlichen Institut der AOK, data year 2020). The characteristics of these drug products were researched from ABDA-Datenbank (ABDATA Pharma-Daten-Service; AVOXA/ABDATA Carl-Mannich-Strasse 26, 65760 Eschborn/Ts., Germany; effective 19.02.2022).

Results: Older adults (n = 52, 67.3% female) participating in the randomized intervention study were between 65 and 94 years old (mean: 81.3 years). Tablets ranging between 250 mg and 1000 mg in weight and differing in shape were all swallowable for the participants. However, only the oval 250 mg tablet was well swallowable¹. According to the visual perception data, participants thought being able to swallow tablets of oval, oblong, or round shape up to a weight of 250 mg. In general, a trend towards a preference of elongated shapes compared to a round shape was especially seen for tablet weights of 500 mg and 750 mg². Data of the handling part showed that all tablets were well to handle for older adults with the exception for the elongated shaped 125 mg tablets². 84.3% of the 300 most prescribed drug products accounted for solid oral dosage forms that needed to be swallowed whole. 94.1% thereof were tablets. Tablets were of round (61.0%), oval (23.3%), oblong (12.6%), and other (3.0%) shape. The proportion of tablets included in the 300 most prescribed drug products deceeding or exceeding the limits of appropriate tablet sizes determined in the randomized intervention study are summarized in Table 2. 11.4% of all tablets were exceeding a tablet weight of 500 mg and hereof 23.1% were of round shape.

Conclusion: In terms of swallowability, it seems that up to a quarter of the tablets, being provided to older adults, are exceeding appropriate size limits. 10% of the tablets might be difficult to handle. However, it is a challenge to identify an appropriate tablet size and shape accommodating the different aspects of patient acceptability. The final decision should be based on the characteristics and impairments of the target patient population.

References: 1 Hummler, H.; Stillhart, C.; Meilicke, L.; Grimm, M.; Krause, E.; Mannaa, M.; Gollasch, M.; Weitschies, W.; Page, S. Impact of Tablet Size and Shape on the Swallowability in Older Adults. Pharmaceutics 2023, 15, 1042.
2 Hummler, H.; Page, S.; Stillhart, C.; Meilicke, L.; Grimm, M.; Mannaa, M.; Gollasch, M.; Weitschies, W. Influence of Solid Oral Dosage Form Characteristics on Swallowability, Visual Perception, and Handling in Older Adults. Pharmaceutics 2023, 15, 1315.

Acknowledgements:

Funding: This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 956146. Disclosure: The study was conducted in accordance with the Declaration of Helsinki, and approved by the Ethics Committee of the University Medicine Greifswald (BB 036/22, 07.04.2022).

Table 1: Tablet characteristics and their inclusion in the different parts of the study.

Table 2: Proportion of most commonly prescribed drug products deceeding or exceeding the limits of appropriate tablet sizes and shapes for swallowability, visual perception, and handling according to the randomized intervention study.