Table 4.
Prevalence of pDDIs in the patients with MS.
| Total Polypharmacy | Rx Polypharmacy | ||||||
|---|---|---|---|---|---|---|---|
| All Patients | PwP | Pw/oP | p Fi | PwP | Pw/oP | p Fi | |
| N | 627 | 334 (53.3%) | 293 (46.7%) | 242 (38.6%) | 385 (61.4%) | ||
| Severity level | |||||||
| Mild | 363 (57.9%) | 297 (88.9%) | 66 (22.5%) | <0.001 | 225 (93.0%) | 138 (35.8%) | <0.001 |
| Mildly moderate | 195 (31.1%) | 175 (52.4%) | 20 (6.8%) | <0.001 | 157 (64.9%) | 38 (9.9%) | <0.001 |
| Moderate | 174 (27.8%) | 155 (46.4%) | 19 (6.5%) | <0.001 | 140 (57.9%) | 34 (8.8%) | <0.001 |
| Moderately severe | 69 (11.0%) | 64 (19.2%) | 5 (1.7%) | <0.001 | 61 (25.2%) | 8 (2.1%) | <0.001 |
| Severe | 7 (1.1%) | 6 (1.8%) | 1 (0.3%) | 0.129 | 5 (2.1%) | 2 (0.5%) | 0.114 |
| No pDDI at all | 227 (36.2%) | 22 (6.6%) | 205 (70.0%) | <0.001 | 7 (2.9%) | 220 (57.1%) | <0.001 |
Each patient who had at least one pDDI of a given category was counted. Note that the patients could have several pDDIs of different severities at the same time. The level of severity of pDDIs was assessed based on MediQ and Stockley’s drug interaction checker. Total polypharmacy = intake of at least five drugs (of any kind). Rx polypharmacy = intake of at least five drugs that were prescribed (neglecting OTC drugs). Chi—chi-squared test; Fi—Fisher’s exact test; MS—multiple sclerosis; N— number of patients; p—p-value for comparing patients with and without polypharmacy; pDDI—potential drug–drug interaction; PwP—patients with polypharmacy; Pw/oP—patients without polypharmacy; Rx—prescription.