Medication Adherence and Its Associated Factors Among Outpatients with Heart Failure

Figures & data

Table 1 Demographic Characteristics of the Participants

Variables		Total Population (n=427)	The 4-Item Morisky Medication Adherence Scale			P-value**
			High Adherence (n= 32)	Moderate Adherence (n= 358)	Low Adherence (n= 38)
		Mean (±SD) or n (%)^a	Mean (±SD) or n (%)^a	Mean (±SD) or n (%)^a	Mean (±SD) or n (%)^a
Age		63 (±12)	60 (±9)	63 (±12)	63 (±12)	0.41
Gender	Male	272 (63.7)	22 (68.8)	227 (63.6)	23 (60.5)	0.77
	Female	155 (36.2)	10 (31.3)	130 (36.3)	15 (39.5)
Body mass index (kg/m2)	Normal (≤24.9)	90 (21.8)	7 (21.9)	77 (22.4)	6 (16.2)	0.74
	Overweight (25–29.9)	161 (39)	14 (43.8)	134 (39)	13 (35.1)
	Obese (≥30)	162 (39.2)	11 (34.4)	133 (38.7)	18 (48.6)
Marital status	Married	404 (94.4)	30 (93.8)	337 (94.1)	37 (97.4)	0.7
	Single/ Divorced/ Widowed	24 (5.6)	2 (6.3)	21 (5.9)	1 (2.6)
Living conditions	Living alone	23 (5.4)	1 (3.1)	20 (5.6)	2 (5.3)	0.84
	Living with family/ other	405 (94.6)	31 (96.9)	338 (94.4)	36 (94.7)
Residency*	Countryside	142 (33.2)	16 (50)	116 (32.4)	10 (26.3)	0.08
	City	286 (66.8)	16 (50)	242 (67.6)	28 (73.7)
Education*	Less than college	297 (69.4)	22 (68.8)	242 (67.6)	33 (86.8)	0.05
	College/ University	131 (30.6)	10 (31.3)	116 (32.4)	5 (13.2)
Working status	Retired/ Unemployed	332 (77.6)	24 (75)	277 (77.4)	31 (81.6)	0.79
	Employed	96 (22.4)	8 (25)	81 (22.6)	7 (18.4)
Monthly income	Less than 500 JD^b	287 (67.1)	22 (68.8)	235 (65.6)	30 (78.9)	0.25
	500–1000 JD^b	141 (32.9)	10 (31.3)	123 (34.4)	8 (21.1)
Smoking status	Non-smoker	299 (69.9)	21 (65.6)	249 (69.6)	29 (76.3)	0.59
	Current smoker	129 (30.1)	11 (34.4)	109 (30.4)	9 (23.7)
Physical Activities	Not active	377 (88.1)	29 (90.6)	317 (88.5)	31 (81.6)	0.41
	Active	51 (11.9)	3 (9.4)	41 (11.5)	7 (18.4)
Family history of cardiovascular diseases	No	219 (51.2)	18 (56.3)	178 (49.7)	23 (60.5)	0.37
	Yes	209 (48.8)	14 (43.8)	180 (50.3)	15 (39.5)

Notes: **P-value for different variables association with adherence levels; *P-value <0.1; ^aStandard deviation; ^bJordanian dinar.

Table 2 Disease and Medication Characteristics of the Study Participants

Variables		Total Population (n=427)	The 4-Item Morisky Medication Adherence Scale			P-value**
			High Adherence (n= 32)	Moderate Adherence (n= 358)	Low Adherence (n= 38)
		Mean (±SD) or n (%)^a	Mean (±SD) or n (%)^a	Mean (±SD) or n (%)^a	Mean (±SD) or n (%)^a
Duration of heart failure (years)		6.41 (±6.16)	5.8 (±6.25)	6.58 (±6.3)	5.16 (±5.08)	0.37
Number of other chronic diseases		3 (±1)	2 (±1)	3 (±1)	3 (±1)	0.19
NYHA classification ^≠*	I/II	130 (30.4)	17 (53.1)	251 (70.1)	30 (78.9)	0.06
	III/IV	298 (69.6)	15 (46.9)	107 (29.9)	8 (21.1)
Type of comorbidities
Hypertension	No	98 (22.9)	9 (28.1)	80 (22.3)	9 (23.7)	0.75
	Yes	330 (77.1)	23 (71.9)	278 (77.7)	29 (76.3)
Diabetes Mellitus*	No	166 (38.8)	18 (56.3)	137 (38.3)	11 (28.9)	0.06
	Yes	262 (61.2)	14 (43.8)	221 (61.7)	27 (71.1)
Ischemic heart diseases	No	153 (35.7)	9 (28.1)	125 (34.9)	19 (50)	0.12
	Yes	275 (64.3)	23 (71.9)	233 (65.1)	19 (50)
Dyslipidemia	No	286 (66.8)	22 (68.8)	242 (67.6)	22 (57.9)	0.47
	Yes	142 (33.2)	10 (31.3)	116 (32.4)	16 (42.1)
Chronic kidney disease*	No	372 (86.9)	31 (96.9)	311 (86.9)	30 (78.9)	0.09
	Yes	56 (13.1)	1 (3.1)	47 (13.1)	8 (21.1)
Thyroid dysfunction*	No	392 (91.6)	32 (100)	323 (90.2)	37 (97.4)	0.06
	Yes	36 (8.4)	0 (0.0)	35 (9.8)	1 (2.6)
Total number of medications		8 (±3)	7 (±3)	8 (±3)	7 (±3)	0.43
Number of heart failure medications		3 (±1)	3 (±1)	3 (±1)	3 (±1)	0.11
Medications frequency	Once	78 (18.2)	6 (18.8)	67 (18.7)	5 (13.2)	0.83
	Twice	249 (58.2)	20 (62.5)	207 (57.8)	22 (57.9)
	Thrice or more	101 (23.6)	6 (18.8)	84 (23.5)	11 (28.9)
Fear of medication side effects *	No	305 (71.3)	21 (65.6)	267 (74.6)	17 (44.7)	<0.001
	Yes	123 (28.7)	11 (34.4)	91 (25.4)	21 (55.3)
Medications satisfaction	No	97 (22.7)	7 (21.9)	78 (21.8)	12 (31.6)	0.39
	Yes	331 (77.3)	25 (78.1)	280 (78.2)	26 (68.4)
Experiencing side effects*	No	291 (68)	19 (59.4)	257 (71.8)	15 (39.5)	<0.001
	Yes	137 (32)	13 (40.6)	101 (28.2)	23 (60.5)
Heart failure medications
Aldosterone antagonist	No	347 (81.0)	29 (90.6)	286 (79.9)	32 (84.2)	0.29
	Yes	81 (18.9)	3 (9.4)	72 (20.1)	6 (15.8)
Digoxin	No	382 (89.3)	31 (96.9)	318 (88.8)	33 (86.8)	0.33
	Yes	46 (10.7)	1 (3.1)	40 (11.2)	5 (13.2)
ACE inhibitor^≠/ ARB^≠*	No	142 (33.2)	7 (21.9)	117 (32.7)	18 (47.4)	0.07
	Yes	286 (66.8)	25 (78.1)	241 (67.3)	20 (52.6)
Beta blocker	No	49 (11.4)	6 (18.8)	36 (10.1)	7 (18.4)	0.12
	Yes	379 (88.6)	26 (81.3)	322 (89.9)	31 (81.6)
Loop diuretic	No	139 (32.5)	13 (40.6)	113 (31.6)	13 (34.2)	0.56
	Yes	289 (67.5)	19 (59.4)	245 (68.4)	25 (65.8)
Vasodilator	No	349 (81.5)	26 (81.3)	292 (81.6)	31 (81.6)	0.99
	Yes	79 (18.5)	6 (18.8)	66 (18.4)	7 (18.4)
Ivabradine	No	408 (95.3)	29 (90.6)	344 (96.1)	35 (92.1)	0.23
	Yes	20 (4.7)	3 (9.4)	14 (3.9)	3 (7.9)
Sacubitril/ Valsartan	No	397 (92.8)	28 (87.5)	331 (92.5)	38 (100)	0.11
	Yes	31 (7.2)	4 (12.5)	27 (7.5)	0 (0.0)
Other medications
Anticoagulant*	No	280 (65.4)	22 (68.8)	240 (67)	18 (47.4)	0.05
	Yes	148 (34.6)	10 (31.3)	118 (33)	20 (52.6)
Statin*	No	125 (29.2)	2 (6.3)	109 (30.4)	14 (36.8)	0.01
	Yes	303 (70.8)	30 (93.8)	249 (69.6)	24 (63.2)
Calcium channel blocker	No	347 (81.1)	28 (87.5)	289 (80.7)	30 (78.9)	0.61
	Yes	81 (18.9)	4 (12.5)	69 (19.3)	8 (21.1)

Notes: **P-value for different variables association with adherence levels; *P-value <0.1; aStandard deviation; ^≠New York Heart Association; ^≠Angiotensin-converting enzyme inhibitor; ^≠Angiotensin-receptor blocker.

Table 3 Biomedical Variables of the Participants

Variable	Total Population (n=427)	The 4-Item Morisky Medication Adherence Scale			P-value**
		High Adherence (n=32)	Moderate Adherence (n=358)	Low Adherence (n=38)
	Mean (±SD)^a	Mean (±SD)^a	Mean (±SD)^a	Mean (±SD)^a
HbA1c (%)	7.28 (±1.97)	7.31 (±2.26)	7.21 (±1.93)	7.9 (±2)	0.1
Triglycerides (mmol/L)	1.96 (±1.169)	2.13 (±1.3)	1.91 (±1.13)	2.3 (±1.35)	0.17
Total cholesterol (mmol/L)*	4.18 (±1.288)	4.74 (±1.96)	4.09 (±1.2)	4.6 (±1.27)	0.03
Low-density lipoprotein (mmol/L)*	2.47 (±1.12)	2.97 (±1.78)	2.39 (±1.04)	2.83 (±1.07)	0.02
High-density lipoprotein (mmol/L)	0.993 (±0.316)	1.03 (±0.28)	0.993 (±0.33)	0.963 (±0.189)	0.71
Serum creatinine (micmol/L)	108.15 (±78.43)	100.36 (±45)	106.17 (±76.4)	131.3 (±107.44)	0.7
Hemoglobin (g/dL)	12.95 (±2.23)	13.31 (±2.2)	12.91 (±2.27)	13.05 (±1.91)	0.63
White blood cells count (109/L)*	8.62 (±2.89)	8.62 (±2.77)	8.61 (±2.86)	8.74 (±3.39)	0.99
Red blood cells count (109/L)*	4.68 (±0.92)	4.78 (±0.77)	4.68 (0.96)	4.61 (±0.71)	0.43
Ejection fraction (%)	42 (±10)	42 (±10)	42 (±10)	43 (±10)	0.76
Systolic blood pressure (mmHg)	129 (±22)	126 (±21)	129 (±21)	134 (±22)	0.2
Diastolic blood pressure (mmHg)	76 (±12)	75 (±8)	76 (±12)	78 (±12)	0.42

Notes: **P-value for different variables association with adherence levels; *P-value <0.1; ^aStandard deviation.

Table 4 Variables Associated with Medication Non-Adherence*

Level of Adherence		OR (95% CI)^ab	P-value
High adherence
Taking ACEIs/ ARBs^cd	No	Reference	0.04
	Yes	3.95 (1.01–15.41)
Taking anticoagulants	Yes	Reference	0.02
	No	4.11 (1.27–13.36)
Taking statins	No	Reference	0.01
	Yes	16.59 (1.79–153.98)
Moderate Adherence
Educational level	High^≠	Reference	0.04
	Low^≠	0.3 (0.1–0.92)
Having medication side effects	Yes	Reference	0.001
	No	4.7 (1.91–11.5)
Taking anticoagulants	Yes	Reference	0.02
	No	2.77 (1.2–6.46)

Notes: *The independent variables that were included in the regression model: total cholesterol, LDL, residency, educational level, NYHA classification, having DM, having CKD, having thyroid dysfunction, having fears of medication side effects, experiencing medication side effects, taking ACEIs/ARBs, taking anticoagulants, and taking statins; ^aOdd ratio; ^bConfidence interval; ^cAngiotensin-converting enzyme inhibitors; ^dAngiotensin-receptor blockers, ^≠High education was defined as a degree from college or more while low education was defined as a degree obtained from primary, secondary or high school.