Table 3.
Studies investigating risk factors for ADR-related hospital admission in older patients
| Study | Country Year conducted | Design | Duration | Settings | Mean/median age (years) | Main outcome measures | Predictors/risk factors |
|---|---|---|---|---|---|---|---|
| Onder et al5 | Italy 1988–1997 | Multicenter pharmacoepidemiology survey | 10 years | Academic hospitals | 70 | ADR severity, potentially responsible drugs, predictors | Female sex (OR 1.30, 95% CI 1.10–1.54) Alcohol use (OR 1.39, 95% CI 1.20–1.60) Number of drugs (OR 1.24, 95% CI 1.20–1.27 for each drug increase) Severe ADRs Age (OR 1.50, 95% CI 1.01–2.23 for age 65–79 years and OR 1.53, 95% CI 1.00–2.33 for age ≥80 years) Comorbidity (OR 1.12, 95% CI 1.05–1.20 for each point in the CCI) Number of drugs (OR 1.18, 95% CI 1.11–1.25 for each drug increase) |
| Marcum et al12 | USA 2004–2006 | Retrospective cohort | 3 years | All admissions (veterans) | 76.4 | ADR causality, preventability, predictors | Polypharmacy (≥9 and 5–8 medications) (AOR 3.90, 95% CI 1.43–10.61 and AOR 2.85, 95% CI 1.0–7.85, respectively) |
| Mannesse et al17 | The Netherlands 1994 | Observational cross-sectional | 3 months | University hospital | 78 | Risk indicators for severe ADRs | Fall before admission (OR 51.3, P=0.006) Gastrointestinal bleeding or hematuria (OR 19.8, P<0.00l) Use of three or more drugs (OR 9.8, P=0.04) |
| Franceschi et al18 | Italy 2004–200S | Prospective cross-sectional | 1 year | Geriatric | 76.5 | ADR prevalence, avoidability | Drug-drug interactions (32.3%) Inappropriate prescription (21.8%) |
| Wawruch et al19 | Slovakia 2003–2005 | Retrospective cross-sectional | 1.4 years | Internal medicine | 76.6 | ADR predictors | Ischemic heart disease (OR 4.50, 95% CI 1.36–14.88) Depression (OR 2.49, 95% CI 1.08–5.77) Heart failure (OR 2.08, 95% CI 1.13–3.81) |
| Wu et al21 | Canada 2003–2008 | Retrospective cohort | 5 years | Emergency department | 77 | Incidence, cost, risk factors | Sex (for females, AOR 0.81, 95% CI 0.72–0.92) Age (AOR 1.03, 95% CI 1.02–1.04) CCI score >3 (AOR 1.86, 95% CI 1.48–2.33) Number of drugs (AOR 1.48, 95% CI 1.13–1.93 for 6–10 drugs and AOR 1.93, 95% CI 1.49–2.51 for > 1 1 drugs) Multiple pharmacies (AOR 1.13, 95% CI 1.00–1.27) Newly prescribed drugs (AOR 1.17, 95% CI 0.93–1.47) Recent hospital admission (AOR 1.47, 95% CI 1.23–1.76) Long-term care residence (AOR 2.08, 95% CI 1.62–2.67) |
| Pedros et al23 | Spain 2009–2010 | Cross-sectional | 120 days | Teaching hospital | 75 | ADR predictors | Age ≥65 years (OR 1.59, 95% CI 1.10–2.29) Number of drugs taken 3–5 (OR 5.07, 95% CI 2.71–9.50), 6–9 (OR 5.90, 95% CI 3.16–1 1.01), and ≥ 10 (OR 8.94, 95% CI 4.73–16.89) |
| Alexopoulou et al24 | Greece 2005 | Prospective cross-sectional | 6 months | University hospital | 65 | Frequency of ADRs, causality, severity, preventability, predictors | Number of drugs (OR 1.064, 95% CI 1.019–1.109) |
| Olivier et al35 | France 2002–2003 | Prospective cross-sectional | 4 weeks | Emergency department | 80.2 | ADR incidence, risk factors | Number of drugs (OR 1.18, 95% CI 1.08–1.29) Self-medication (OR 2.34, 95% CI 1.18–4.66) Use of antithrombotics (OR 2.26, 95% CI 1.33–3.88) Use of antibacterial drugs (OR 4.04, 95% CI 1.50–10.83) |
| Malhotra et al37 | India 2000 | Prospective cross-sectional | 7 months | Emergency department | 72.5 | Risk factors | Number of drugs ≥3 (OR 4.3) Consulting >3 physicians (OR 5.7) Living alone (OR 4.3) |
| Chen et al38 | Taiwan 2009–2010 | Prospective case-control | 1 year | Emergency department | 65 | Risk factors | Number of drugs (AOR 4.1, 95% CI 2.4–6.9 for 3–7 drugs; AOR 6.4, 95% CI 3.7–11.0 for eight or more drugs) and increased concentration of serum creatinine (AOR 1.5, 95% CI 1.1–2.2) |
| Zhang et al41 | Australia 2005 | Retrospective cohort | Records of ADR admission from 1980 to 2000 and followed for 3 years | All public and private hospitals | Mean age not reported, study in patients aged ≥60 years | ADR predictors | Sex(HR 1.08, 95% CI 1.02–1.15, for men) First admission in 1995–1999 (HR 2.34, 95% CI 2.00–2.73) Length of hospital stay (HR 1.1 1, 95% CI 1.05–1.18, for stays ≥ 14 days) CCI (HR 1.71, 95% CI 1.46–1.99, for score ≥7) Comorbid congestive cardiac failure (HR 1.56, 95% CI 1.43–1.71), peripheral vascular disease (HR 1.27, 95% CI 1.09–1.48), chronic pulmonary disease (HR 1.61, 95% CI 1.45–1.79), rheumatological disease (HR 1.65, 95% CI 1.41–1.92), mild liver disease (HR 1.48, 95% CI 1.05–2.07), moderate to severe liver disease (HR 1.85, 95% CI 1.18–2.92), moderate diabetes (HR 1.18, 95% CI 1.07–1.30), diabetes with chronic complications (HR 1.91, 95% CI 1.65–2.22), renal disease (HR 1.93, 95% CI 1.71–2.17), any malignancy including lymphoma and leukemia (HR 1.87, 95% CI 1.68–2.09), and metastatic solid tumors (HR 2.25, 95% CI 1.92–2.64) |
Abbreviations: ADR, adverse drug reaction; OR, odds ratio; CI, confidence interval; CCI, Charlson Comorbidity Index; AOR, adjusted odds ratio; HR, hazard ratio.