Table 4. Univariate and multivariate analyses on factors associated with occurrences of drug interactions in the drug therapy prescribed for 255 older adults at hospital discharge.
| Description | Interactions | Univariate analysis | Multivariate analysis | |||
|---|---|---|---|---|---|---|
| Variable | Frequency | |||||
|
|
Odds ratio (95% CI) | P-value | Odds ratio (95% CI) | P-value | |
| Sociodemographic characteristics | ||||||
| Gender | ||||||
| Female | 103 (59.5%) | 43 (52.4%) | 1.33 (0.79-2.26) | 0.28 | ||
| Male | 70 (40.5%) | 39 (45.6%) | 1 | |||
| Age | ||||||
| ≥75 | 91 (52.6%) | 49 (59.8%) | 0.75 (0.44-1.27) | 0.28 | ||
| <75 | 82 (47.4%) | 33 (40.2 %) | 1 | |||
| Clinical characteristics | ||||||
| Geriatric unit | ||||||
| Yes | 58 (33.5%) | 39 (47.6%) | 0.56 (0.32-0.95) | 0.03* | 0.45 (0.22-0.89) | 0.02 |
| No | 115 (66.5%) | 43 (52.4%) | 1 | 1 | ||
| Stroke | ||||||
| Yes | 26 (15.0%) | 11 (13.4%) | 1.14 (0.53-2.44) | 0.73 | ||
| No | 147 (85.0%) | 71 (86.6%) | 1 | |||
| Heart failure | ||||||
| Yes | 35 (20.2%) | 3 (3.7%) | 6.68 (1.99-22.42) | 0.00* | ||
| No | 138 (79.8%) | 79 (96.3%) | 1 | |||
| COPD | ||||||
| Yes | 25 (14.5%) | 9 (11.0%) | 1.37 (0.61-3.09) | 0.45 | ||
| No | 148 (85.5%) | 73 (89.0%) | 1 | |||
| Cancer | ||||||
| Yes | 18 (10.4%) | 11 (13.4%) | 0.75 (0.34-1.67) | 0.48 | ||
| No | 155 (89.6%) | 71 (86.6%) | 1 | |||
| Diabetes mellitus | ||||||
| Yes | 90 (52.0%) | 20 (24.4%) | 3.36 (1.87-6.04) | 0.00* | 2.16 (1.05-4.44) | 0.04 |
| No | 83 (48.0%) | 62 (75.6%) | 1 | 1 | ||
| Pneumonia | ||||||
| Yes | 32 (18.5%) | 21 (25.6%) | 0.66 (0.35-1.23) | 0.19* | ||
| No | 141 (81.5%) | 61 (74.4%) | 1 | |||
| Dementia | ||||||
| Yes | 50 (28.9%) | 29 (35.4%) | 0.74 (0.42-1.30) | 0.30 | ||
| No | 123 (71.1%) | 53 (64.6%) | 1 | |||
| Hypothyroidism | ||||||
| Yes | 39 (22.5%) | 4 (4.9%) | 5.67 (1.95-16.48) | 0.00* | 7.29 (2.03-26.10) | 0.00 |
| No | 134 (77.5%) | 78 (95.1%) | 1 | 1 | ||
| Chronic kidney disease | ||||||
| Yes | 40 (23.1%) | 5 (6.1%) | 4.63 (1.75-12.23) | 0.00* | 3.41 (1.09-10.64) | 0.03 |
| No | 133 (76.9%) | 77 (93.9%) | 1 | 1 | ||
| Peripheral vascular disease | ||||||
| Yes | 9 (5.2%) | 7 (8.5%) | 0.59 (0.21-1.64) | 0.30 | ||
| No | 164 (94.8%) | 75 (91.5%) | 1 | |||
| Asthma | ||||||
| Yes | 3 (1.7%) | 0 (0.0%) | 1.48 (1.36-1.61) | 0.55** | ||
| No | 170 (98.3%) | 82 (100.0%) | 1 | |||
| Arterial hypertension | ||||||
| Yes | 131 (75.7%) | 50 (61.0%) | 1.99 (1.14-3.51) | 0.01* | ||
| No | 42 (24.3%) | 32 (39.0%) | 1 | |||
| Acute myocardial infarction | ||||||
| Yes | 16 (9.2%) | 3 (3.7%) | 2.68 (0.76-9.48) | 0.11* | ||
| No | 157 (90.8%) | 79 (96.3%) | 1 | |||
| Depression | ||||||
| Yes | 36 (20.8%) | 10 (12.2%) | 1.89 (0.89-4.03) | 0.09 | ||
| No | 137 (79.2%) | 72 (87.8%) | 1 | |||
| Functional characteristics | ||||||
| VES-13 median | ||||||
| ≥ 5 | 90 (52.0%) | 46 (56.1%) | 0.85 (0.50-1.44) | 0.54 | ||
| < 5 | 83 (48.0%) | 36 (43.9%) | 1 | |||
| Drug therapy-related characteristics | ||||||
| Polypharmacy with 5 drugs | ||||||
| Yes | 149 (86.1%) | 25 (30.5%) | 14.15 (7.48-26.79) | 0.00* | 12.62 (6.25-25.50) | 0.00 |
| No | 24 (13.9%) | 57(69.5%) | 1 | 1 | ||
| MRCI index | ||||||
| Yes | 117 (67.6%) | 16 (19.5%) | 8.62 (4.58-16.22) | 0.00* | ||
| No | 56 (32.4%) | 66 (80.5%) | 1 | |||
*P-value < 0.2: variable selected for the multivariate logistic regression; **P-value was calculated using Fisher’s exact test; Hosmer-Lemeshow test: chi-square = 4.958; degrees of freedom = 7; P = 0.665.
CI = confidence interval; COPD = chronic obstructive pulmonary disease; VES-13 = Vulnerable Elders Survey-13; MRCI = Medication Regimen Complexity Index.