Extent and reasons for nonadherence to antihypertensive, cholesterol, and diabetes medications: the association with depressive symptom burden in a sample of American veterans

Figures & data

Table 1 Comparison of survey responders and non-responders

	Completed survey				P-value
	Yes (n=1,026)		No (n=974)
	N	%	N	%
Age in years (mean, SD)	70.0	9.7	69.0	10.7	0.036
Age (n, %)
>65 years	303	29.5	341	35.0	0.010
40–64 years	723	70.5	633	65.0
Sex (n, %)
Male	969	94.4	934	95.9	0.145
Female	57	5.56	40	4.1
Race (n, %)
White	687	67.0	569	58.4	<0.001
Black	290	28.3	369	37.9
Other	21	2.1	22	2.3
Unknown	28	2.7	14	1.4
Marital status (n, %)
Married	679	66.2	570	58.5	0.001
Divorced/widowed	216	21.0	241	24.7
Single/never married	95	9.3	101	10.4
Unknown	36	3.5	62	6.4
Pays health care copay (n, %)
Yes	287	28.0	227	23.3	0.019
No	739	72.0	746	76.6
Missing	0	0.0	1	0.1
Pays prescription copay (n, %)
Yes	711	69.3	605	62.1	0.001
No	315	30.7	368	37.8
Missing	0	0.0	1	0.1
Gagne comorbidity score (median, IQR)	0.3	1.5	0.0	1.3	0.012
Number of conditions (mean, SD)	6.39	5.0	6.50	5.0	0.613
Number of VA prescribers (n, %)
0	52	5.1	63	6.5	0.025
1	628	61.2	540	55.4
2	232	23.6	226	23.2
3	70	6.8	80	8.2
4	44	4.3	64	6.7

Notes: P-values were estimated with two- sample t-test for age and number of conditions; with Wilcoxon rank sums for the Gagne Score; and with Fisher’s exact test for all others.

Abbreviations: IQR, interquartile range; SD, standard deviation; VA, veterans’ affairs.

Table 2 Unadjusted percent self-reported adherence and nonadherence by condition

Covariate	Hypertension		P-value	Dyslipidemia		P-value	Type 2 diabetes		P-value
	Adherent n=578	Nonadherent n=338		Adherent n=518	Nonadherent n=330		Adherent n=279	Nonadherent n=168
Depressive symptoms
MHI >65 (yes)	59.9	40.1	0.059	54.1	45.9	0.001	58.6	41.4	0.102
MHI <65 (no)	65.2	34.8		65.6	34.4		64.9	35.1
Age (years)
40–64	59.2	40.8	0.034	54.3	45.7	0.001	58.2	41.8	0.092
65+	65.3	34.5		65.3	34.7		65.0	35.0
Sex
Male	63.8	36.2	0.068	61.4	38.6	0.264	63.9	36.1	0.009
Female	52.7	42.3		55.6	44.4		38.5	61.5
Race
White	65.1	34.9	0.139	66.0	34.0	<0.001	65.8	34.2	0.145
Black	58.2	41.8		51.2	48.3		56.2	43.8
Other	66.7	33.3		53.1	46.9		62.5	37.5
Marital
Married	63.9	36.1	0.390	64.5	35.6	0.013	64.7	35.3	0.389
Divorced/widowed	61.7	38.3		52.5	47.5		58.1	41.9
Never married	58.8	41.2		55.8	44.2		56.9	43.1
Unknown	100	0.0		40.0	60.0		100.0	0.0
Pays health care copay
Yes	61.3	38.7	0.797	67.1	32.9	0.058	66.4	33.6	0.528
No	63.6	36.4		58.8	41.2		61.3	38.7
Unknown	66.7	36.9
Pays prescription copay
Yes	60.9	39.1	0.118	62.0	38.0	0.759	62.9	37.1	0.924
No	68.2	31.8		59.0	41.0		61.6	38.4
Unknown	66.7	33.3
Number of conditions
1	85.7	14.3	0.458			0.792			0.879
2	62.2	37.8		62.4	37.6		65.8	34.2
3	64.2	35.8		60.1	39.9		61.6	38.4
4	55.6	44.4		58.8	41.2		60.7	39.3
Number of VA prescribers
0	62.6	37.4	0.278			0.433			0.157
1	63.7	36.3		60.6	39.4		65.5	34.5
2	63.2	36.8		57.5	42.5		63.9	36.1
3	53.9	46.2		61.8	38.2		43.6	56.4
4	72.7	27.3		60.4	39.6		63.4	36.6

Note: Percentages and P-values estimated using Fisher’s exact test.

Abbreviations: MHI, Mental Health Inventory; VA, veterans’ affairs.

Table 3 Adjusted self-reported nonadherence by condition

Condition	Hypertension n=917		Dyslipidemia n=849		Type 2 diabetes n=437
Covariate	OR	P-value	OR	P-value	OR	P-value
High depressive symptom burden	1.24	0.149	1.42	0.025	1.15	0.512
Age ≥65 years	0.77	0.087	0.74	0.058	0.84	0.450
Female	1.55	0.139	0.88	0.706	2.55	0.041
Race
Black	1.38	0.045	1.59	0.005	1.39	0.139
Other	0.87	0.727	1.65	0.196	0.83	0.75
Marital status
Divorced/widowed	1.03	0.875	1.55	0.016	1.23	0.401
Single/never married	1.03	0.265	1.21	0.325	1.01	0.969
Pays health care copay	1.19	0.347	0.94	0.723	0.98	0.938
Pays prescription copay	1.45	0.038	1.17	0.381	1.09	0.72
Number of conditions
3	0.90	0.464	0.99	0.944	1.04	0.877
4	1.51	0.254	1.11	0.792	1.25	0.633
Number of VA prescribers
1	0.88	0.523	1.34	0.199	0.82	0.496
2	0.87	0.562	1.40	0.187	0.73	0.355
3	1.33	0.341	1.05	0.338	1.81	0.162
4	0.63	0.199	1.16	0.683	0.83	0.674

Abbreviations: OR, odds ratio; VA, veterans’ affairs.

Table 4 Frequency and percent of reported reasons for nonadherence by depressive symptom burden and condition

Condition		Hypertension					Dyslipidemia					Type 2 diabetes
No	Item	Low (n=192)		High (n=146)		FDR-p	Low (n=175)		High (n=155)		FDR-p	Low (n=87)		High (n=80)		FDR-p
		Freq	%	Freq	%		Freq	%	Freq	%		Freq	%	Freq	%
	Negative expectations or worry
4	I worried about taking them for the rest of my life	22	12.64	38	29.92	<0.001	15	9.87	36	26.47	<0.001	7	8.97	18	26.87	0.070
10	I was afraid of becoming dependent on them	10	5.88	15	15.20	0.018	14	9.21	24	17.52	0.012	5	6.49	6	9.09	0.692
11	I was afraid they may affect my sexual performance	22	12.64	39	29.77	<0.001	19	12.18	33	23.24	<0.001	10	12.82	16	25.53	0.070
19	I was afraid the medication would interact with other medication I take	17	9.94	21	17.21	0.038	10	6.58	21	15.11	0.030	5	6.49	9	13.85	0.070
	Poor memory
2	I forgot	78	43.33	70	51.85	0.095	59	37.82	76	52.78	0.011	41	5.62	31	41.89	0.787
18	I ran out of medication	44	25.73	41	31.78	0.117	31	20.0	39	27.66	0.044	22	28.21	16	24.24	0.436
	Complex medication regimen
15	I was supposed to take them too many times a day	4	2.35	14	11.38	0.013	7	4.64	16	11.68	0.012	4	5.19	8	12.12	0.070
16	I had other medications to take	17	10.06	30	24.39	0.015	15	9.87	24	17.65	0.013	8	10.39	7	10.94	0.692
	Concerns about drug effects
3	The medication caused some side effects	23	13.07	25	19.84	0.046	22	14.47	33	24.09	0.012	10	12.82	19	27.94	0.070
17	They make me need to urinate too often	30	17.34	35	28.23	<0.001	20	13.16	28	20.44	0.012	12	15.38	13	19.70	0.184
20	My (lab measure) was too low	32	18.29	19	15.57	0.623	13	8.44	13	9.42	0.716	20	25.64	22	33.33	0.428
21	I was feeling too ill to take them	18	1.47	22	18.18	0.044	11	7.19	24	17.78	0.012	10	12.82	9	13.85	0.353
	Does not take condition seriously
13	I felt I did not need them	24	14.20	20	16.53	0.407	18	11.92	23	16.55	0.081	10	12.99	13	19.70	0.184
7	I did not have any symptoms of (condition)	33	19.19	27	22.50	0.033	21	13.82	24	18.05	0.081	18	22.78	17	25.37	0.977
	Financial burden
5	They cost a lot of money	27	15.61	32	25.20	<0.001	14	9.40	25	18.25	<0.001	10	12.82	11	16.18	0.153
	Interferes with lifestyle
1	I was busy	26	14.86	33	25.78	0.015	21	13.82	26	18.71	0.025	14	18.18	13	19.12	0.692
6	I came home late	32	18.5	28	23.14	0.414	28	18.79	25	18.25	0.559	19	25.33	16	23.19	0.738
8	I was with friends or family members	31	17.92	26	21.49	0.117	20	13.25	24	17.52	0.116	13	16.88	9	13.24	0.911
9	I was in a public place	20	11.83	18	14.88	0.300	16	10.67	16	11.85	0.523	11	14.29	6	8.96	0.869
12	The time to take them was between my meals	18	10.47	18	14.52	0.06	17	11.04	18	12.86	0.287	7	8.97	15	22.39	0.070
14	I was traveling	40	22.99	26	2.63	0.843	32	21.05	23	16.91	0.716	27	34.62	13	19.40	0.911

Abbreviation: FDR-p, false discovery rate P-value; Freq, response frequency.

Table 5 Adjusted odds of self-reported reasons for nonadherence among participants with high depressive symptom burden

Condition		Hypertension (n=338)		Dyslipidemia (n=330)		Type 2 diabetes (n=167)
No	Item	OR	FDR-p	OR	FDR-p	OR	FDR-p
	Negative expectations/worry
4	I worried about taking them for the rest of my life	3.09	0.011	3.63	0.021	4.96	0.105
10	I was afraid of becoming dependent on them	2.38	0.152	2.13	0.119	1.44	0.818
11	I was afraid they may affect my sexual performance	3.09	0.011	2.34	0.084	3.41	0.205
19	I was afraid the medication would interact with other medications I take	2.27	0.108	2.64	0.105	2.79	0.391
	Poor memory
2	I forgot	1.44	0.263	1.71	0.116	0.70	0.53
18	I ran out of medication Complex medication regimen	1.54	0.252	1.61	0.206	0.94	0.979
15	I was supposed to take them too many times a day	6.52	0.017	2.40	0.185	3.38	0.348
16	I had other medications to take	3.11	0.011	1.70	0.282	0.98	0.979
	Concerns about drug effects
3	The medication caused some side effects	1.42	0.479	2.03	0.116	2.88	0.205
17	They make me need to urinate too often	2.33	0.028	2.04	0.116	3.10	0.252
20	My (lab measure) was too low	1.07	0.854	1.36	0.573	1.57	0.488
21	I was feeling too ill to take them	1.57	0.386	2.76	0.084	1.16	0.922
	Does not take condition seriously
13	I felt I did not need them	1.62	0.252	1.45	0.452	1.78	0.445
7	I did not have any symptoms of (condition)	1.26	0.613	1.38	0.503	2.54	0.348
	Financial burden
5	They cost a lot of money	2.86	0.011	3.17	0.042	1.96	0.445
	Interferes with lifestyle
1	I was busy	1.90	0.126	1.50	0.402	0.86	0.922
6	I came home late	1.22	0.613	0.91	0.85	0.53	0.445
8	I was with friends or family members	1.20	0.621	1.40	0.483	1.02	0.979
9	I was in a public place	1.31	0.613	1.00	0.999	0.64	0.652
12	The time to take them was between my meals	1.31	0.613	1.05	0.951	3.81	0.205

Abbreviations: FDR-p, false discovery rate P-value; OR, odds ratio.