Recent trends in tablet subdivision and factors affecting subdivision in South Korea: A cross-sectional study

Tablet subdivision by physicians or patients frequently occurs in various clinical settings for multiple reasons, including dose adjustment, alleviation of swallowing difficulties, or cost savings. However, not all tablets are suitable for subdivision, and it might cause side effects. It is informative to know which medicines are regularly subdivided, which healthcare institutions prescribe subdivided medicines, and to whom the medicines are prescribed from the perspectives of quality of care and patient safety. In this study, we aimed to examine recent trends in tablet subdivision and to address factors associated with subdivision of tablets both at the patient and healthcare institution levels. The yearly claims data in 2016 retrieved from the National Patients Sample provided by the Health Insurance Review and Assessment (HIRA-NPS). This study used descriptive statistics to examine characteristics of medicines that were frequently prescribed in subdivided forms, and retrieved information regarding the medicines to assess the appropriateness for tablet splitting. Then, we selected five medicines, and performed a multivariate logistic regression analysis to estimate the effect of the variables of interest on tablet subdivision. We presented the top 25 medicines prescribed in subdivided forms in 2016, and confirmed these medicines could be relevantly halved according to their Summary of Product Characteristics. Of the 25 medicines, 14 (56%), 5 (20%), and 3 (12%) medicines belonged to the respiratory system (R), nervous system (N), and systemic hormonal preparations (H), according to the first category of Anatomical Therapeutic Chemical (ATC) classification system, respectively. Being female at the patient level and tertiary healthcare institutions and private owned institutions at the institution level were positively associated with subdivision of medicines. Subdivision of tablets frequently occurred for vulnerable populations with various reasons. Female and geriatric patients are prescribed split medicines for clinical reasons, while low-income patients are prescribed nonsplit medicines for cost savings. It would be better if medicines were not so small, and if they had dividing lines on their surfaces to enable successful splitting of the tablet and to protect the health of vulnerable patients. Furthermore, avoid splitting those pharmacotherapies with a narrow therapeutic range, and provide a pharmacist assistance and a splitting device for unavoidable splitting.