Busier Pharmacies Become Hubs for the Sickest Homebound Patients, Study Finds

As populations around the world age at an unprecedented pace, the quiet backbone of home-based medical care is increasingly made up of professionals who do not wear white coats in hospitals at all: pharmacists who travel to their patients. Visiting pharmacist services, now reported in eleven countries, send medication experts directly into the homes of older adults who can no longer easily reach a community pharmacy. A new population-based study from Japan, published in BMC Health Services Research, offers one of the most detailed looks yet at how these services actually operate, and its findings carry a message with implications far beyond the Tokyo suburb where the data were collected.

The research team, led by Reina Taguchi of the Institute for Health Economics and Policy in Tokyo along with colleagues at the University of Tokyo and other Japanese institutions, asked a deceptively simple question: does the size of a pharmacy’s visiting practice shape the kind of patients it serves, the resources it deploys, and the medication outcomes those patients experience? To answer it, the investigators turned to an unusually rich data source — linked medical and long-term care insurance claims from a single city in Tokyo, allowing them to track both health care use and care needs for the same individuals over time.

The study population consisted of adults aged 65 and older who began using visiting pharmacist services between fiscal years 2015 and 2018. In total, 2,699 older adults were identified. Rather than treating all pharmacies as interchangeable, the researchers grouped them into tertiles according to their annual patient volume, creating low-, medium-, and high-volume categories. This design allowed the team to compare patient characteristics, medication profiles, and pharmacy attributes across the spectrum of practice scale, and then to follow medication counts over time using sophisticated statistical modeling.

The first striking finding concerns who ends up on the caseloads of busy pharmacies. High-volume pharmacies were not simply scaled-up versions of their smaller counterparts; they served a categorically different patient population. Their patients were younger but clinically far more complex, and the proportion of patients with terminal cancer was dramatically higher — 21.2 percent at high-volume pharmacies compared with just 6.3 percent at low-volume ones, a difference that was highly statistically significant. In other words, the largest visiting pharmacy practices have become de facto hubs for patients at the most fragile and medically demanding end of the home care spectrum.

That concentration of complexity is mirrored, and quite plausibly enabled, by the pharmacies’ staffing. High-volume pharmacies employed a median of nine full-time pharmacists, compared with a median of just three at low-volume practices — again a difference that reached statistical significance at p less than 0.001. This is not a trivial distinction in a field where round-the-clock availability, rapid response to symptom changes, and coordination with physicians and home nurses all demand substantial personnel. The pattern suggests a structural division of labor: larger practices, with deeper staffing reserves, absorb the patients whose conditions change fastest and whose medication regimens are most demanding to manage.

The longitudinal heart of the study focused on a subset of 2,005 participants for whom complete medication trajectory data were available. The researchers modeled the number of medications each patient was taking over time using linear mixed-effects models — a statistical framework well suited to repeated measures nested within individuals, who are themselves nested within pharmacies. The models included random intercepts at both levels and adjusted for recent hospitalization, a critical control because hospital discharges are precisely the moments when medication lists balloon. Potentially inappropriate medications were assessed with tools including the Japanese Anticholinergic Risk Scale, reflecting the particular risks of anticholinergic burden in older adults.

What the trajectories revealed is perhaps the study’s most consequential result. Before visiting pharmacist services began, patients’ medication counts were climbing steadily, at a rate of roughly 0.16 additional drugs per month — a familiar and worrying pattern of prescribing cascade in deteriorating patients. After service initiation, that climb all but stopped: medication counts rose by only about 0.03 drugs per month. The change in slope, a reduction of 0.13 drugs per month with a 95 percent confidence interval of −0.16 to −0.10, was statistically robust. In plain terms, the introduction of a visiting pharmacist marked a turning point at which runaway polypharmacy was brought under control.

Equally important is what did not differ. This stabilization effect held consistently across all three pharmacy volume groups, from the smallest practices to the largest hubs. Whatever advantages scale confers in staffing and patient mix, the fundamental benefit of a pharmacist regularly entering the home — reconciling medication lists, deprescribing where appropriate, coordinating with prescribers after hospitalizations — appears to operate regardless of practice size. The authors interpret this as evidence that visiting pharmacists engage at key care-transition points, the moments when patients are most vulnerable to medication errors and accumulation.

The findings arrive at a moment when health systems worldwide are scrambling to design sustainable home care workforces. Japan, one of the fastest-aging societies on Earth, has built an elaborate architecture of home medical care including home care support clinics and hospitals, and visiting pharmacist services are an explicit pillar of that system. By showing that patient volume is strongly associated with case complexity and staffing depth, the study provides empirical input for workforce planning: reimbursement models that assume all visiting pharmacies are interchangeable may systematically undervalue the high-volume hubs that shoulder the most complex, end-of-life cases.

There are limits worth keeping in mind. The study is retrospective and draws on claims data from a single Japanese city, Hachioji, whose data infrastructure made the analysis possible; generalization to other health systems requires care. Claims data also capture what was dispensed rather than every nuance of clinical decision-making. Yet the core message stands on solid ground: in aging societies, the pharmacies that visit the most patients tend to care for the sickest, and they do it with proportionally larger full-time teams — while the act of bringing a pharmacist into the home reliably halts the relentless growth of medication burden. As other nations expand home-based care, that combination of structural insight and clinical reassurance is exactly the kind of evidence policy will need.

Subject of Research: Visiting pharmacist services and medication management among older adults receiving home-based care in Japan

Article Title: Pharmacy patient volume and visiting Pharmacist services: variation in patient characteristics, pharmacy attributes, and medication changes

Article References: Taguchi, R., Okada, A., Tsuchiya-Ito, R., Kitamura, S., Ishikawa, T., & Hamada, S. (2026). Pharmacy patient volume and visiting Pharmacist services: variation in patient characteristics, pharmacy attributes, and medication changes. BMC Health Services Research. https://doi.org/10.1186/s12913-026-15673-x

Image Credits: AI Generated

DOI: 10.1186/s12913-026-15673-x

Keywords: visiting pharmacist services, polypharmacy, home-based care, aging population, long-term care, potentially inappropriate medications, pharmacy patient volume, claims data, care transitions, Japan, health services research, medication management