11. tbl. 97. árg. 2011
Quality indicators of drug therapy at hospital admission among elderly patients
Vísbendingar um gæði lyfjameðferða aldraðra við innlögn á Landspítala
Objective: Increased morbidity and higher prevalence of medication use commonly coexists among the elderly. When managed appropriately, older patients can benefit from drug therapy. However, drug related problems are more frequent and more serious in the elderly. The aim of the study was to assess the quality of medication use in older people at hospital admission.
Material and methods: A retrospective medical record review was performed for patients 70 years and older who had an unplanned admission to the internal medicine and geriatric units at Landspitali University Hospital in 2007. Among the sampled medical records, 913 met inclusion criteria. Assessment was carried out using 15 drug-specific quality indicators.
Results: Mean age was 80.9 years and 54.5% were women. Mean number of drugs at admission was 7.0 for women and 6.5 for men (p=0.047). The prevalence of having one or more quality indicators on admission was 48.4%. Women were more likely to have a quality indicator than men (women 56.2%, men 39.9%). The probability also increased with increasing age and number of drugs.
Conclusions: The quality of drug therapy among older patients at hospital admission appears to be suboptimal. A more accurate estimate of the problem could be obtained through a prospective study where drug regimens are correlated with symptoms and reason for admission. Additional studies are also needed in the outpatient setting. Such studies could provide more accurate evidence and assist policy making towards improved quality of drug prescribing for a growing number of older patients.
Table I. Drug use quality indicators.
| Quality indicator | Drug and/or ATC code | Concern |
|
Tricyclic antidepressants 4,6,11 |
Amitryptiline (N06AA09), Trimipramine (N06AA06), Doxapin (N06AA12), Chlomipramine (N06AA04) | Strong anticholinergic and sedative properties increase the risk for impaired cognitive functioning, urinary retention (males), constipation, impaired vision, falls and fractures. |
| Amitryptiline 15,24 | N06AA09 | Strong anticholinergic and sedative properties increase the risk for impaired cognitive functioning, urinary retention (males), constipation, impaired vision, falls and fractures. |
| First-generation antipsychotics 4,6 |
Chlorpromazine (N05AA01), Chlorprotixene (N05AF03), Levoprometazine (N05AA02), Prochlorperazine (N05AB04) |
Strong anticholinergic and sedative properties. May cause extrapyramidal and orthostatic hypotension. |
| Long-acting benzodiazepines 4,6,9,11 | Nitrazepam (N05CD02), Flunitrazepam (N05CD03) | Long half-life and risk of accumulation may produce prolonged sedation and increase the risk of falls. |
| Benzodiazepines 4,6,9 | N05BA, N05CD | Risk of accumulation and increase the risk of falls and impaired cognitive function. |
| First-generation anthistamines 4,6,9 | Dexchlorphenamine (R06AB02), Promethazine (R06AD02), Alimemazine (R06AD01), Hydroxycin (N05BB01) |
Strong anticholinergic properties. Especially Promethazine og Alimemazine may cause extrapyramidal symptoms. |
| Beta blocking agent + unselective calcium channel blocker 4,6,9 | Beta blocking agent (C07A), Verapamil (C08DA01) Diltiazem (C08DB01) | A nonselective calcium channel blocker in combination with a beta blocking agent may cause myocardial depression and atrioventricular block. |
| NSAID + warfarin 4,6,9,19 | NSAID (M01AB, M01AC, M01AE), warfarin (B01AA03) | Increased risk of gastrointestinal bleeding. |
| NSAID + ACE inhibitor or A2-blocker 4,6 |
NSAID (M01AB, M01AC, M01AE), ACE inhibitors (C09A, C09B), A2 blockers (C09C, C09D) |
May cause kidney failure in elderly patients, particularly if presence of general arteriosclerosis, dehydration or concurrent use of diuretics. |
| NSAID + SSRI 4,6 |
NSAID (M01AB, M01AC, M01AE), SSRI (N06AB) |
Increased risk of gastrointestinal bleeding. |
| NSAID + diuretic 4,6 | NSAID (M01AB, M01AC, M01AE), diuretics (C03) | May reduce the effect of diuretics and worsen existing heart failure. |
| Aspirin + warfarin 19 | Aspirin (N02BA01, B01AC06), warfarin (B01AA03) | Increased risk of bleeding. |
| Hypnotic 24 | N05C | Increased risk of falls and impaired cognitive function. |
|
Three or more psychotropic drugs 6 |
Opioids (N02A), Psychotropic drugs (N05), Antidepressant drugs (N06A) |
Increased risk of excessive sedation, interactions and central nervous adverse effects. |
|
Three or more psychotropic drugs-2 (excepting opioids)24 |
Psychotropic drugs (N05), Antidepressant drugs (N06A) |
Increased risk of excessive sedation, interactions and central nervous adverse effects. |
Table II. Number and proportion of patients with quality indicators by gender.
| Quality indicators | Women (n=498) |
Men (n=415) |
Total (n=913) |
p-value
|
| Tricyclic antidepressants | 24 (4.8%) | 7 (1.7%) | 31 (3.4%) | 0.009 |
| Amitryptiline | 14 (2.8%) | 7 (1.7%) | 21 (2.3%) | 0.259 |
| First-generation antipsychotics | 13 (2.6%) | 9 (2.2%) | 22 (2.4%) | 0.665 |
| Long-acting benzodiazepines | 8 (1.6%) | 7 (1.7%) | 15 (1.6%) | 0.924 |
| Benzodiazepines | 115 (23.1%) | 58 (14.0%) | 173 (18.9%) | 0.000 |
| First-generation anthistamines | 21 (4.2%) | 12 (2.9%) | 33 (3.6%) | 0.285 |
| Beta blocking agent + unselective calcium channel blocker | 7 (1.4%) | 6 (1.4%) | 13 (1.4%) | 0.959 |
| NSAID + warfarin | 8 (1.6%) | 4 (1.0%) | 12 (1.3%) | 0.396 |
| NSAID + ACE inhibitor or A2-blocker | 17 (3.4%) | 7 (1.7%) | 24 (2.6%) | 0.104 |
| NSAID + SSRI | 9 (1.8%) | 3 (0.7%) | 12 (1.3%) | 0.152 |
| NSAID + diuretic | 19 (3.8%) | 7 (1.7%) | 26 (2.8%) | 0.054 |
| Aspirin + Warfarin | 15 (3.0%) | 26 (6.3%) | 41 (4.5%) | 0.018 |
| Three or more psychotropic drugs | 84 (16.9%) | 37 (8.9%) | 121 (13.3%) | 0.000 |
| Three or more psychotropic drugs-2 | 69 (13.9%) | 31 (7.5%) | 100 (11.0%) | 0.002 |
| Hypnotic | 204 (41.0%) | 103 (24.8%) | 307 (33.6%) | 0.000 |
Table III. Mean number of drugs according to number of quality indicators. Number of quality indicators are divided into four ranges.
| Number of quality indicators | Mean number of drugs |
Standard deviation |
95% CI |
| 0 | 4.97 | 3.11 | 4.69 – 5.25 |
| 1 | 7.76 | 3.26 | 7.33 – 8.19 |
| 2-3 | 8.46 | 3.78 | 7.81 – 9.11 |
| ≥ 4 | 11.28 | 3.94 | 10.45 – 12.11 |
Table IV. Logistic regression model predicting whether or not a patient has a quality indicator.
| Variables | Coefficient | p - value | OR |
| Age in years | 0.030 | 0.012 | 1.031 |
| Male gender | - 0.699 | 0.000 | 0.497 |
| Number of drugs at admission | 0.325 | 0.000 | 1.384 |
| Constant | -4.366 | 0.000 | 0.013 |
| χ2 (p-value) | 263.522 (p = 0.000) | ||
| N | 913 | ||
| Nagelkerke R square | 0.334 | ||
Figure 1. Proportion of patients distributed according to number of drugs at hospital admission by gender.