Table 1.

Demographic characteristics in 827 hospitalized patients

	Group 1: ≥ 5 drugs on admission, No. of patients =391	Group 2: <5 drugs on admission, No. of patients =436	Difference between groups
			95% CI*	P-values†
Gender, no. female (%)	246 (62.9)	239 (54.8)	(1, 15)	0.02
	Mean (SD)	Mean (SD)
	[range]	[range]
Age, years	75.4 (12.76)	66.7 (19.41)	(−11.0, −6.5)	<0.01
	[21–98]	[15–98]
No. of drugs per patient used on admission	7.3 (2.35)	2.1 (1.42)	(−5.4, −4.9)	<0.01
	[5–16]	[0–4]
No. of clinical/pharmacological risk factors per patient	2.45 (1.18)	0.88 (0.96)	(−1.7, −1.4)	<0.01
	[1–6]	[1–5]
Clinical/pharmacological risk factors for having a DRP‡	% of 391 patients	% of 436 patients
	(no. of patients)	(no. of patients)
Diabetes mellitus	15.9 (62)	7.1 (31)	(4, 13)	<0.01
Cardiac failure	25.6 (100)	11.2 (49)	(9, 20)	<0.01
Reduced renal function	26.3 (103)	12.2 (53)	(9, 20)	<0.01
Reduced liver function	1.8 (7)	2.1 (9)	(−2, 2)	0.80
History of allergy or adverse reactions to drugs	16.1 (62)	14.7 (64)	(−4, 6)	0.65
Non-adherence	3.6 (14)	3.4 (15)	(−2, 3)	0.91
Use of drugs with narrow therapeutic index	39.6 (155)	22.2 (97)	(11, 24)	<0.01
Others	16.1 (63)	14.7 (64)	(−3, 6)	0.58

^*95% confidence interval for the difference between groups, given in percentage for categorical variables and mean difference for continuous variables.

^†Significant when P< 0.05.

^‡DRP, Drug-related problem.