Inappropriate prescribing of antithrombotic therapy in Ethiopian elderly population using updated 2015 STOPP/START criteria: a cross-sectional study

Figures & data

Table 1 Characteristics and clinical data of the study population in Gondar University Hospital, Gondar, Ethiopia, between May 1, 2013 and April 30, 2015

Patient characteristics and clinical data	N (%)
Total number of study population, N	156
Age in years, mean (SD)	72.3 (±7.0)
Sex, n (%)
Male	57 (36.5)
Female	99 (63.5)
Hospital stay in days (median)	13 (range 1–55)
Reason of admission, n (%)
CHF	41 (26.3)
VTE	9 (5.8)
Stroke	59 (37.8)
AF	15 (9.6)
ACS	19 (12.2)
PVD	2 (1.3)
Other	11 (7.1)
Number of medications prescribed, mean ± SD	4.92±1.86
Charlson comorbidity index (median)	2 (range 0–7)
Past history of peptic ulcer disease, n (%)
Yes	19 (12.2)
No	37 (87.8)
History of recent bleeding, n (%)
Yes	11 (7)
No	145 (93)
History of coronary disease, cerebrovascular disease, or PVD, n (%)
Yes	63 (40.4)
No	93 (59.6)
Types of antithrombotic therapy, n (%)
No therapy	16 (10.2)
Anticoagulant only	34 (21.8)
Antiplatelet only	68 (43.6)
Both	38 (24.4)

Notes: Others in “reason of admission” refers to hospitalization due to any medical condition other than listed cardiovascular disease, but have either a known comorbidity of cardiovascular disease or a history of coronary disease, cerebrovascular disease, or PVD; anticoagulants identified are warfarin, unfractionated heparin, and low-molecular-weight heparin (enoxaparin); antiplatelets prescribed are aspirin and clopidogrel.

Abbreviations: ACS, acute coronary syndrome; AF, atrial fibrillation; CHF, congestive heart failure; PVD, peripheral vascular disease; VTE, venous thromboembolism; SD, standard deviation.

Table 2 PIMs of antithrombotic therapy identified by the STOPP criteria version 2 at Gondar University Hospital, Gondar, Ethiopia, between May 1, 2013 and April 30, 2015

STOPP criteria version 2	Number (%)
Any drug prescribed without an evidence-based clinical indication	5 (13.9)
Any drug prescribed beyond the recommended duration, where treatment duration is well defined	1 (2.8)
Any duplicate drug class prescription	–
Long-term aspirin at doses >160 mg/day	–
Aspirin with a past history of peptic ulcer disease without concomitant PPI	2 (5.6)
Aspirin, clopidogrel, dipyridamole, vitamin K antagonists, direct TIs, or factor Xa inhibitors with concurrent significant bleeding risk (uncontrolled severe hypertension, bleeding diathesis, recent nontrivial spontaneous bleeding)	7 (19.4)
Aspirin plus clopidogrel as secondary stroke prevention, unless the patient has a coronary stent(s) inserted in the previous 12 months or concurrent acute coronary syndrome or has a high-grade symptomatic carotid arterial stenosis	–
Aspirin in combination with vitamin K antagonist, direct TI, or factor Xa inhibitors in patients with chronic atrial fibrillation	10 (27.8)
Antiplatelet agents with vitamin K antagonist, direct TI, or factor Xa inhibitors in patients with stable coronary disease, cerebrovascular disease, or PAD	6 (16.7)
Ticlopidine in any circumstances	–
Vitamin K antagonist, direct TI, or factor Xa inhibitors for first deep venous thrombosis without continuing provoking risk factors (eg, thrombophilia) for >6 months	1 (2.8)
Vitamin K antagonist, direct TI, or factor Xa inhibitors for first pulmonary embolus without continuing provoking risk factors for >12 months	–
NSAID and vitamin K antagonist, direct TI, or factor Xa inhibitors in combination	1 (2.8)
NSAID with concurrent antiplatelet agent(s) without PPI prophylaxis	3 (8.3)
Total number of antithrombotic-related PIMs	36

Notes: This table consists of antithrombotic-specific STOPP criteria extracted from STOPP/START criteria version 2. “-” indicates no PIMs observed.

Abbreviations: NSAID, nonsteroidal anti-inflammatory drugs; PAD, peripheral arterial disease; PIMs, potentially inappropriate medicines; PPI, proton pump inhibitor; START, Screening Tool to Alert doctors to Right Treatment; STOPP, Screening Tool for Older Person’s Prescription; TI, thrombin inhibitor.

Table 3 PPOs of antithrombotic therapy identified by the START criteria version 2 at Gondar University Hospital, Gondar, Ethiopia, between May 1, 2013 and April 30, 2015

START criteria version 2	Number (%)
Vitamin K antagonists, direct TIs, or factor Xa inhibitors in the presence of chronic AF	14 (41.2)
Aspirin (75 mg–160 mg once daily) in the presence of chronic AF, where vitamin K antagonists, direct TIs, or factor Xa inhibitors are contraindicated	1 (2.9)
Antiplatelet therapy (aspirin, clopidogrel, prasugrel, or ticagrelor) with a documented history of coronary disease, cerebrovascular disease, or PVD	19 (55.9)
Total number of antithrombotic-related PPOs	34

Note: This table consists of antithrombotic-specific START criteria extracted from STOPP/START criteria version 2.

Abbreviations: AF, atrial fibrillation; PPO, potential prescribing omissions; PVD, peripheral vascular disease; START, Screening Tool to Alert doctors to Right Treatment; STOPP, Screening Tool for Older Person’s Prescription; TI, thrombin inhibitor.

Figure 1 Proportion of IP exposure across different types of antithrombotic therapy per patient at Gondar University Hospital, Gondar, Ethiopia, between May 1, 2013 and April 30, 2015.

Notes: In this study, anticoagulants identified are warfarin, unfractionated heparin, and low-molecular-weight heparin (enoxaparin); antiplatelets prescribed are aspirin and clopidogrel.

Abbreviation: IP, inappropriate prescribing.

Figure 2 Prevalence of IP by the primary diagnosis of the patient at Gondar University Hospital, Gondar, Ethiopia, between May 1, 2013 and April 30, 2015.

Notes: Others in “reason of admission” refer to hospitalization due to any medical condition other than listed cardiovascular disease, but have either a known comorbidity of cardiovascular disease or a history of coronary disease, cerebrovascular disease, or PVD.
Abbreviations: ACS, acute coronary syndrome; AF, atrial fibrillation; CHF, congestive heart failure; IP, inappropriate prescribing; PVD, peripheral vascular disease; VTE, venous thromboembolism.

Table 4 Relationship between predictive variables and inappropriate prescribing exposure at Gondar University Hospital, Gondar, Ethiopia, between May 1, 2013 and April 30, 2015

Variables	IP per patient		OR (95% CI)		P-value
	Absent	Present	COR	AOR
Age
≥85	9	4	1	1	–
65–74	59	33	0.795 (0.23–2.78)	0.50 (0.12, 2.49)	0.397
75–84	30	21	0.64 (0.17–2.34)	0.35 (0.08–1.78)	0.204
Sex
Female	60	39	1	1	–
Male	38	19	0.769 (0.39–1.52)	0.83 (0.35, 1.97)	0.671
Days of hospital stay (mean)	14.2	14.69	0.99 (0.97–1.027)	1.02 (0.97, 1.06)	0.451
Reason of admission					0.33
Other	6	5	1	1	–
CHF	19	22	0.72 (0.19–2.74)	1.71 (0.30, 9.66)	0.545
VTE	8	1	6.67 (0.61–73.03)	29.87 (1.26, 708.6)*	0.035
Stroke	43	16	2.24 (0.59–8.37)	7.74 (1.27, 47.29)*	0.027
AF	5	10	0.42 (0.08–2.06)	1.55 (0.18, 13.09)	0.687
ACS	15	4	3.13 (0.618–15.79)	13.48 (1.41, 129.13)*	0.024
PVD	2	0	134 (0.00– NA)	425 (0.00– NA)	0.999
Number of medications prescribed (mean)	4.4	5.45	0.78 (0.64, 0.934)*	0.85 (0.65, 1.11)	0.22
Charlson comorbidity index (mean)	2.02	2.34	0.76 (0.55, 1.03)	0.60 (0.39, 0.945)*	0.027
Past history of PUD
No	87	50	1	1	–
Yes	11	8	0.79 (0.298, 2.095)	1.55 (0.42, 5.72)	0.51
History of recent bleeding
No	91	54	1	1	–
Yes	7	4	1.04 (0.29–3.71)	2.71 (0.48, 15.52)	0.26
History of coronary disease, cerebrovascular disease, or PVD
No	64	29	1	1	–
Yes	34	29	0.53 (0.27–1.03)	0.49 (0.18, 1.36)	0.173
Types of antithrombotic therapy					0.001
Both	21	17	1	1	–
No therapy	4	12	3.80 (1.02–14.21)	0.34 (0.05, 2.46)	0.283
Anticoagulant only	19	15	11.57 (3.23–41.42)*	1.26 (0.304, 5.22)	0.750
Antiplatelet only	54	14	3.71 (1.01–13.59)**	6.23 (1.90, 20.37)**	0.002

Notes:

* P<0.05,

** P<0.01. “-” indicates reference variable. Data in bold indicates statistical significance (P<0.05).

Abbreviations: ACS, acute coronary syndrome; AF, atrial fibrillation; AOR, adjusted odds ratio; CHF, congestive heart failure; CI, confidence interval; COR, crude odds ratio; IP, inappropriate prescriptions; OR, odds ratio; PAD, peripheral arterial disease; PPI, proton pump inhibitor; PVD, peripheral vascular disease; PUD, peptic ulcer disease; VTE, venous thromboembolism; NA, not applicable.