ArticleCureus2025
Polypharmacy and Its Spatial Clustering in Japan: An Ecological Study of the Standardized Polypharmacy Ratio.
Article in Cureus, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
0 citing papers in PubMed.
No citing paper in PubMed yet.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
3 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundPolypharmacy, defined as the concurrent use of multiple medications, poses significant health risks, particularly among aging populations. While polypharmacy is a recognized concern, limited research has examined its spatial distribution or its association with demographic and socioeconomic factors. This study aimed to examine the spatial patterns of polypharmacy across Japan and identify regional characteristics associated with higher polypharmacy rates. This study could contribute to evaluating the effectiveness of current local and national policies and may also inform future policy initiatives.
methodsAn ecological study was conducted across 335 local health units in Japan using data from national health, demographic, and geographic databases. Polypharmacy was defined as prescriptions containing seven or more drugs, and the standardized polypharmacy ratio (SPR) was calculated by age-group population. Spatial autocorrelation of SPR was assessed using Moran's I statistic. Clustering analysis incorporating SPR and regional variables identified distinct high-risk areas.
resultsThe prediction model for polypharmacy prescriptions achieved an R² of 0.98, indicating high accuracy, though SPR remained heterogeneous. Significant spatial autocorrelation was observed for both polypharmacy prescriptions (Moran's I = 0.4; P < 0.001) and SPR (Moran's I = 0.24; P < 0.001), highlighting regional clustering. Clustering analysis identified four groups by polypharmacy risk (critical, high, moderate, and low). High-SPR areas were associated with higher population density, a greater proportion of younger adults (ages 20 to 60), and increased levels of education, income, and tertiary industry workers.
conclusionPolypharmacy in Japan exhibits significant spatial clustering, with higher rates in urbanized regions driven by demographic and socioeconomic factors. Region-specific interventions addressing these unique characteristics are essential for improving polypharmacy management.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.