Table 2.
Characteristics of the selected studies
| First author | Year of publication | Country | Definition of polypharmacy | Study design | Participants | Mean age (SD) | Patients with poly pharmacy |
|---|---|---|---|---|---|---|---|
| Bağ Soytaş [19] | 2021 | Turkey | ≥ 5 | Retrospective study | 218 | 75.3 | 108 |
| Bayrak [20] | 2022 | Turkey | ≥ 5 | Prospective study | 122 | 73 | 59 |
| Cantudo-Cuenca [21] | 2021 | Spain | ≥ 5 | observational study | 174 | 67 | 92 |
| Carrillo-Garcia [22] | 2021 | Spain | ≥ 5 | Longitudinal study | 165 | 88.5 | 112 |
| Couderc [23] | 2021 | France | ≥ 5 | Retrospective study | 480 | 88 | 348 |
| Crescioli [17] | 2021 | Italy | > 5 | Case series | 23 | 76.1 (14.40) | 16 |
| De Smet [24] | 2020 | Belgium | ≥ 5 | Retrospective study | 81 | 85 | 52 |
| Gavin et al. [25] | 2020 | America | ≥ 5 | Retrospective chart review | 140 | 60 | NR |
| Kananen et al. [26] | 2021 | Sweden | ≥ 5 | observational study | 1409 | 83(12) | NR |
| Klanidhi [27] | 2022 | India | ≥ 5 | Prospective study | 60 | 68.76 | 23 |
| Laosa [28] | 2020 | Spain | ≥ 5 | Prospective study | 375 | 66.06 | 77 |
| Lim et al. [29] | 2021 | Singapore | ≥ 4 | Observational study | 275 | 59 (54–66) | 73 |
| Lozano-Montoya [30] | 2021 | Spain | ≥ 5 | Longitudinal study | 300 | 86.3 | 213 |
| Manjhi [31] | 2021 | India | ≥ 5 | Retrospective study | 200 | > 40 | 142 |
| Mannucci [18] | 2022 | Italy | ≥ 5 | Observational study | 48,148 | NR | 7464 |
| McKeigue et al. [32] | 2021 | Scotland | ≥ 5 | Matched case control | 4251 | 0–75, ≥ 75 | NR |
| McQueenie et al. 1 [2] | 2020 | England | 4–6 | Retrospective study | 1324 | 48–86 | 298 |
| McQueenie et al. 2 [2] | 2020 | England | 6–9 | Retrospective study | 1324 | 48–86 | 130 |
| McQueenie et al. 3 [2] | 2020 | England | > 10 | Retrospective study | 1324 | 48–86 | 72 |
| Poblador-Plou [33] | 2020 | Spain | ≥ 5 | Retrospective study | 4412 | 67.7 | 1429 |
| Rodriguez-Sanchez [34] | 2021 | Spain | 5_9 | Cohort study | 499 | 86.7 | 200 |
| Rodriguez-Sanchez [34] | 2021 | Spain | > 10 | Cohort study | 499 | 86.7 | 163 |
| Sirois 1 [35] | 2022 | Canada | 5–9 | Population-based study | 32,476 | 79.59 | 9579 |
| Sirois 2 [35] | 2022 | Canada | 10–14 | Population-based study | 32,476 | 79.59 | 8619 |
| Sirois 3 [35] | 2022 | Canada | 15–19 | Population-based study | 32,476 | 79.59 | 5009 |
| Sirois 4 [35] | 2022 | Canada | ≥ 20 | Population-based study | 32,476 | 79.59 | 3746 |
| Sun et al. [36] | 2020 | China | ≥ 5 | Retrospective study | 217 | 45.7 (16.6) | NR |
| Taher [37] | 2020 | Bahrain | ≥ 5 | Retrospective study | 73 | 54 | 43 |