Pharmacologically inappropriate prescriptions for elderly patients in general practice: How common?

Figures & data

Table I.  The Prescription Peer Academic Detailing (Rx-PAD) study: Characteristics of participating general practitioners (n = 454).

	Males (n = 312)	Females (n = 141)
Age, mean (SD)	50.3 (8.0)	45.4 (7.4)*
Years licensed, mean (SD)	20.4 (8.7)	14.9 (8.0)*
Patients ≥70 years, mean (SD)	212.7 (89.4)	137.5 (67.6)*
Group practice,%	90.7	94.3
Specialist GP,%	89.7	76.6**

*p < 0.01 (two samples t-test); **p < 0.01 (chi-squared test).

Table II.  Prevalence of inappropriate drug prescriptions (Rx) issued for patients ≥70 years by 454 Norwegian general practitioners.

Drugs or combinations of drugs to be avoided for elderly patients for reasons of safety	Mean (95% CI) Rx/100 patients ≥70 years
Tricyclic antidepressants	2.2 (2.0–2.3)
(amitryptiline, doxepin, trimipramine, clomipramine)
Anticholinergic effects, better alternatives exist
First-generation (low potency) antipsychotics	2.6 (2.4–2.8)
(chlorpromazine, chlorprotixene, levoprometazine, prochlorperazine)
Anticholinergic effects, extrapyramidal effects, risk of falls and cognitive impairment
Long-acting benzodiazepines	4.6 (4.3–4.9)
(nitrazepam, flunitrazepam)
Risk of accumulation, prolonged sedation, falls and fractures
Strong analgesics	1.1 (1.0–1.2)
(propoxyphene, pethidine, opioids with spasmolytics)
Poorly tolerated by elderly, propoxyphene has narrow therapeutic width
Risk of sedation, confusion, falls and fractures
First-generation antihistamines	2.5 (2.3–2.6)
(dexchlorphenamine, promethazine, alimemazine, hydroxycin)
Anticholinergic effects, risk of “hangover”
Long time oral use of theophylline	0.5 (0.5–0.6)
Risk of cardiac arrhythmias
No documented effect on COPD or asthma in the elderly, better alternatives exist
Carisoprodol (muscle relaxant)	1.0 (0.9–1.1)
Anticholinergic effects, poorly tolerated by elderly, risk of muscle weakness, falls and fractures
Beta blocking agent + unselective calcium channel blocker	0.6 (0.5–0.6)
May lead to AV block and myocardial depression
NSAID + warfarin (any concomitant use)	0.3 (0.3–0.4)
Risk of gastrointestinal bleeding due to impaired platelet function
NSAID + ACE inhibitor or A2-blocker (any concomitant use)	3.4 (3.2–3.6)
Risk of drug induced renal failure
NSAID + SSRI (any concomitant use)	0.8 (0.7–0.9)
Increased risk of gastrointestinal bleeding
NSAID + diuretic (any concomitant use)	2.4 (2.2–2.5)
Reduced effect of diuretics
Three or more psychotropic drugs (analgesics containing opioids, psycholeptics, hypnotics, antidepressants) for ≥3 months	2.8 (2.6–3.0)
Total	24.7 (23.7–25.6)

Table III.  Determinants for level of inappropriate drug prescription to patients ≥70 years among 454 Norwegian general practitioners.¹

	Prescriptions per 100 patients ≥70 years Mean (SD)		p-value
Doctor's sex (male/female)	25.7 (10.3)	22.3 (10.4)	0.001
Group practice (no/yes)	31.1 (11.0)	24.1 (10.2)	< 0.001
Specialist general practitioner (yes/no)	25.8 (9.9)	17.8 (11.0)	< 0.001

Note: ¹Bivariate analyses, categorical variables: Two samples t-test.

Table IV.  Determinants for level of inappropriate drug prescription to patients ≥70 years among 454 Norwegian general practitioners.¹

	Prescriptions per 100 patients ≥70 years Pearson's correlation coefficient	p-value
Years since licence	0.344	0.001
Patients ≥70 years	0.272	<0.001

Note: ¹Bivariate analyses, continuous variables: Pearson correlation.

Table V.  Determinants for level of inappropriate drug prescription to patients ≥70 years among 454 Norwegian general practitioners.¹

	Unstandardized B (SE)	p-value
(Constant)	13.91 (3.46)	<0.001
Doctor's sex	0.23 (1.1)	0.83
Years licensed	0.26 (0.06)	<0.001
Group practice	5.62 (1.64)	0.001
Specialist GP	−3.75 (1.48)	0.01
Patients ≥70 years	0.02 (0.006)	<0.001

Note: ¹Multiple linear regression, dependent variable is number of inappropriate prescriptions per 100 patients ≥70 years.