Table 1

Selection of studies demonstrating international variation in prevalence of prescribed polypharmacy in community and primary care settings

StudySettingSample sizeAge of participantsNumber of medicationsRates of polypharmacy (%)Notes
Hovstadius et al9Sweden, primary care9 219 637Total population≥5
≥10
11.1
 2.4
Rates of polypharmacy increased with age.
60–69 years≥5
≥10
21.4
 4.1
≥80 years≥5
≥10
52.3
15.5
Qato et al72USA, community300557–85 years≥529Rates of polypharmacy increased with age and female gender.
Dong et al73Rural China, primary healthcare clinics20 125 prescriptionsTotal population≥5 5.8Village doctor workload and government subsidies influenced the rates of polypharmacy. Rates are per prescription rather than per person.
Richardson et al74Ireland, community8093≥50 years≥5
≥10
19
 2
Rates of polypharmacy were greatest in those with self-reported hypertension, hypercholesterolaemia, arthritis, chronic pain and diabetes.
Oliveira et al75Brazil, primary care142≥60 years≥464.5Small study.
Payne et al7Scotland, primary care180 815Total adult population4–9
≥10
16.9
 4.6
Polypharmacy increased with the number of long-term conditions.
60–69 years4–9
≥10
28.6
 7.4
≥80 years4–9
≥10
51.8
18.6