Determinants of medication adherence among adults with type 2 diabetes mellitus in three Malaysian public health clinics: a cross-sectional study

Figures & data

Table 1 Patient characteristics according to medication adherence categories

Patient characteristics	Total patients, n (column %)	Medication adherence score, n (row %)		χ^2	P-value*
		Low (MMAS-8 <6)	Medium and high (MMAS-8 6–8)
Health clinic				0.96	0.620
Seri Kembangan	216 (32.3)	94 (43.5)	122 (56.5)
Dengkil	121 (13.1)	47 (38.8)	74 (61.2)
Salak	331 (49.3)	145 (43.8)	186 (56.2)
Age, years				9.18	0.010
≤50	174 (26.1)	88 (50.6)	86 (49.4)
51–60	260 (39.0)	115 (44.2)	145 (55.8)
>60	232 (34.8)	83 (35.8)	149 (64.2)
Diabetes duration, years				2.77	0.251
<5	323 (50.0)	130 (40.2)	193 (59.8)
5–9.9	183 (28.3)	78 (42.6)	105 (57.4)
≥10	140 (21.7)	68 (48.6)	72 (51.4)
Sex				0.24	0.638
Female	359 (54.0)	157 (43.7)	202 (56.3)
Male	306 (46.0)	128 (41.8)	178 (58.2)
Ethnicity				7.58	0.023
Malay	351 (53.0)	158 (45.0)	193 (55.0)
Chinese	155 (23.4)	73 (47.1)	82 (52.9)
Indian	156 (23.6)	52 (33.3)	104 (66.7)
Religion				11.45	0.043
No religion	32 (4.8)	11 (34.4)	21 (65.6)
Moslem	359 (53.9)	161 (44.8)	198 (55.2)
Buddhist	78 (11.7)	43 (55.1)	35 (44.9)
Hinduism/Sikh	141 (21.2)	48 (34.0)	93 (66.0)
Christian/Catholic	21 (3.2)	8 (38.1)	13 (61.9)
Others	35 (5.3)	13 (37.1)	22 (62.9)
Religiosity				0.18	0.912
Religious	567 (85.4)	242 (42.7)	325 (57.3)
Unsure	24 (3.6)	10 (41.7)	14 (58.3)
Not religious	73 (11.0)	33 (45.2)	40 (54.8)
Marital status				2.12	0.547
Married/living with a partner	523 (78.8)	227 (43.4)	296 (56.6)
Widowed	96 (14.5)	36 (37.5)	60 (62.5)
Divorced/separated	19 (2.9)	10 (52.6)	9 (47.4)
Single	26 (3.9)	10 (38.5)	16 (61.5)
Education				9.72	0.008
Never	43 (6.5)	16 (37.2)	27 (62.8)
Primary and secondary	542 (82.5)	222 (41.0)	320 (59.0)
Tertiary	72 (11.0)	43 (59.7)	29 (40.3)
Employment				2.51	0.285
Retired/home manager	356 (53.5)	144 (40.4)	212 (59.6)
Employed	299 (45.0)	134 (44.8)	165 (55.2)
Unemployed	10 (1.5)	6 (60.0)	4 (40.0)
Income (RM)				11.42	0.003
<1,000	310 (47.1)	118 (38.1)	192 (61.9)
1,000–2,999	310 (47.1)	138 (44.5)	172 (55.5)
≥3,000	38 (5.8)	25 (65.8)	13 (34.2)
Exercise				19.42	<0.0001
No	283 (42.6)	114 (40.3)	169 (59.7)
≤3 times in a week	220 (33.1)	119 (54.1)	101 (45.9)
>3 times in a week	161 (24.2)	52 (32.3)	109 (67.7)
Smoking				3.20	0.202
Never	509 (76.5)	209 (41.1)	300 (58.9)
Stopped >5 years	59 (8.9)	27 (45.8)	32 (54.2)
Stopped ≤5 years and active smoker	97 (14.6)	49 (50.5)	48 (49.5)
Hypertension				0.48	0.502
No	140 (21.3)	64 (45.7)	76 (54.3)
Yes	516 (78.7)	219 (42.4)	297 (57.6)
Dyslipidemia				0.18	0.686
No	381 (59.3)	167 (43.8)	214 (56.2)
Yes	261 (40.7)	110 (42.1)	151 (57.9)
Any diabetes complication				0.27	0.635
No	585 (87.7)	253 (43.2)	332 (56.8)
Yes	82 (12.3)	33 (40.2)	49 (59.8)
Any microvascular complication				0.22	0.658
No	617 (92.5)	263 (42.6)	354 (57.4)
Yes	50 (7.5)	23 (46.0)	27 (54.0)
Any macrovascular complication				0.30	0.628
No	622 (93.8)	270 (43.4)	352 (56.6)
Yes	41 (6.2)	16 (39.0)	25 (61.0)
OHA				1.91	0.169
No	58 (8.7)	30 (51.7)	28 (48.3)
Yes	605 (91.3)	256 (42.3)	349 (57.7)
Insulin				0.51	0.777
None	403 (60.9)	170 (42.2)	233 (57.8)
1 type	183 (27.6)	81 (44.3)	102 (55.7)
≥2 types	76 (11.5)	35 (46.1)	41 (53.9)
Number of AHA agents				1.22	0.748
None	80 (12.1)	35 (43.8)	45 (56.3)
1 type	197 (29.8)	90 (45.7)	107 (54.3)
2 types	191 (28.9)	83 (43.5)	108 (56.5)
≥3 types	194 (29.3)	78 (40.2)	116 (59.8)

Note:

* Chi-square P-value.

Abbreviations: MMAS-8, 8-item Morisky Medication Adherence Scale; OHA, oral hypoglycemic agent; AHA, antihypertensive agent; RM, Ringgit Malaysia.

Figure 1 Distribution of MMAS-8 total score.

Abbreviations: MMAS-8, 8-item Medication Morisky Adherence Scale; SD, standard deviation.

Table 2 Determinants of medication adherence

Parameter	Crude Exp (B)	95% CI for crude Exp (B)		Significance	Adjusted Exp (B), n=597	95% CI for adjusted Exp (B)		Significance
		Lower	Upper			Lower	Upper
Intercept	NA	NA	NA	NA	4.67	3.519	6.190	<0.0001
Age, n=665	1.004	1.002	1.006	<0.0001	1.003	1.001	1.006	0.019
Ethnicity, n=661
Indian	1.08	1.017	1.139	0.011	1.05	0.988	1.110	0.118
Chinese	1.004	0.948	1.062	0.900	0.98	0.923	1.046	0.589
Malay	1	NA	NA	NA	1	NA	NA	NA
Income, n=657
≥3,000	0.83	0.747	0.913	<0.0001	0.90	0.803	0.999	0.048
1,000–2,999	0.95	0.910	0.999	0.046	0.988	0.947	1.051	0.937
<1,000	1	NA	NA	NA	1	NA	NA	NA
Education, n=656
Tertiary	0.85	0.76	0.95	0.004	0.91	0.804	1.028	0.128
Primary and secondary	0.96	0.879	1.057	0.437	0.99	0.895	1.084	0.759
Never	1	NA	NA	NA	1	NA	NA	NA
Exercise, n=663
No	0.97	0.916	1.028	0.309	0.99	0.932	1.049	0.705
≤3 times in a week	0.92	0.870	0.982	0.011	0.98	0.915	1.040	0.452
>3 times in a week	1	NA	NA	NA	1	NA	NA	NA
OQOL, n=597	1.004	1.002	1.007	0.001	1.002	0.999	1.004	0.211
DDS, n=639	0.997	0.996	0.999	<0.0001	0.999	0.998	1.001	0.546
PHQ, n=654	0.98	0.978	0.988	<0.0001	0.988	0.981	0.994	<0.0001

Abbreviations: Exp (B), odds ratio; CI, confidence interval; OQOL, overall score for the World Health Organization Quality of Life-Brief 26 items; DDS, Diabetes Distress Scale 17 items; PHQ, Patient Health Questionnaire 9 items; NA, not applicable.