Medication and medical diagnosis as risk factors for falls in older hospitalized patients.

OBJECTIVE: To examine the impact of medication and medical conditions on the fall risk in older hospitalized patients.

DESIGN: Matched case-control study.

SETTING: Large regional hospital in a mid-sized German city.

SUBJECTS: Four hundred eighty-one inpatients aged ≥ 65 years who fell during hospitalization ("cases") and a control group of 481 controls, matched for age, gender, and hospital department.

METHODS: Diagnosis, medication, vital parameters, and injuries were compared between cases and controls. Univariate and multivariable odds ratios (ORs) and their corresponding 95% confidence intervals (CIs) were calculated.

MAIN RESULTS: Several drugs were significantly associated with falls in multivariate analyses: long-acting benzodiazepines (adjusted OR = 3.49; 95%-CI = 1.16-10.52), serotonin-noradrenalin reuptake inhibitors (SNRI) (2.57; 1.23-5.12), Z-drugs (2.29; 1.38-3.59), low-potency neuroleptics (1.87; 1.08-3.23), ACE inhibitors/sartans (1.42; 1.07-1.89). Digoxin (0.32; 0.11-0.99) and aldosterone receptor antagonists (0.54; 0.33-0.88) were negatively associated with falls. No significant association in multivariate analyses was found for short- and intermediate-acting benzodiazepines, mirtazapine, and opioids. Hyponatremia (1.52; 1.15-2.03) and leukocytosis (1.39; 1.05-1.87) in blood examination on admission showed significant association with falls. As secondary diagnoses, Parkinson syndrome (2.38; 1.27-4.46) and delirium (3.74; 2.26-6.21) were strongly associated with falls. The use of more than one psychoactive drug was a separate risk factor for falls (p < 0.0001).

CONCLUSION: Several drugs including SNRI, neuroleptics, and Z-drugs showed a significant association with inpatient falls. The frequently prescribed tetracyclic antidepressant mirtazapine did not appear to increase the risk of falls. Psychoactive polypharmacy should be avoided.