Self-reported adherence to oral cancer therapy: relationships with symptom distress, depression, and personal characteristics

Figures & data

Table 1 Patient characteristics for all (N=70) and for those with self-reported low/medium adherence and high adherence to oral cancer medications

Patient characteristic	Overall N (%)	Low/medium adherence	High adherence
		N (%)	N (%)
N	70	21	49
Age, median (range), years	61 (34–80)	56 (34–75)	62 (39–80)
Minority	9 (14)	3 (14)	6 (12)
Sex
Male	42 (60)	8 (38)	34 (69)
Female	28 (40)	13 (62)	15 (31)
Study group
Control	39 (56)	15 (71)	24 (49)
Intervention	31 (44)	6 (29)	25 (51)
Cancer type
Breast	19 (27)	6 (29)	13 (27)
Colorectal	1 (1)	1 (5)	0 (0)
Other GI	6 (9)	2 (10)	4 (8)
Prostate	31 (44)	6 (29)	25 (51)
Renal cell	6 (9)	3 (14)	3 (6)
Sarcoma	5 (7)	2 (10)	3 (6)
Other	2 (3)	1 (5)	1 (2)
Therapy type
Chemotherapy	29 (41)	13 (62)	16 (33)
Hormonal therapy	41 (59)	8 (38)	33 (67)
Months on oral agents, median (range)	2.27 (0.39–14.01)	2.10 (0.46–14.01)	2.34 (0.39–4.70)
Stage
0	2 (3)	2 (10)	0 (0)
1	8 (11)	2 (10)	6 (12)
2	27 (39)	3 (14)	24 (49)
3	10 (14)	4 (19)	6 (12)
4	22 (31)	9 (43)	13 (27)
True missing*	1 (1)	1 (5)	0 (0)
Working (N=62)	40 (65)	8 (47)	32 (71)
Education (N=69)
≤HS	12 (17)	4 (20)	8 (16)
>HS	57 (83)	16 (80)	41 (84)
Married/partnered	61 (87)	14 (67)	47 (96)

Note:

* indicates a non-solid tumor.

Abbreviations: GI, gastrointestinal; HS, high school.

Table 2 Item response frequencies of nonadherent behavior on the MMAS-8 adapted to the cancer setting

Item	Total	Control	Intervention
	N (%)	N (%)	N (%)
	70	39	31
Sometimes forget to take OCM?	9 (13)	8 (21)	1 (3)
Over past 2 weeks, any days OCM not taken?	7 (10)	3 (8)	4 (13)
Ever cut back or stopped OCM without telling the doctor because you felt worse when taking it?	1 (1)	0 (0)	1 (3)
When traveling, do you forget to bring OCM?	2 (3)	2 (5)	0 (0)
Did you take your OCM yesterday?	7 (10)	4 (10)	3 (10)
When you feel cancer is under control, do you stop taking OCM?	1 (1)	0 (0)	1 (3)
Do you feel hassled about sticking to cancer plan?	6 (9)	4 (10)	2 (6)
How often do you have difficulty remembering to take OCM?	1 (1): sometimes	1 (1)	0 (0)
	5 (7): once in a while	5 (13)	0 (0)
Have you taken more than regular dose?	1 (1)	1 (3)	0 (0)

Note: N=70.

Abbreviations: MMAS, Morisky Medication Adherence Scale; OCM, oral chemotherapy medicine.

Table 3 Univariate odds of low/medium adherence

Variable	Univariate
	OR (95% CI)	P-value
SDS-15+1 vs SDS-15a	1.1 (1.0–1.2)	0.09
PHQ9C+1 vs PHQ9Ca	1.2 (1.0–1.4)	0.05
Chemotherapy vs hormonal therapy	3.4 (1.2–9.7)	0.03
Female vs male	3.7 (1.3–10.7)	0.02
Stage 4 vs stages 0–3	2.3 (0.8–6.7)	0.14
Control vs treatment	2.6 (0.9–7.8)	0.09
Working vs not working	0.4 (0.1–1.1)	0.08
≤HS vs >HS	1.3 (0.3–4.9)	0.72
Minority vs nonminority	1.3 (0.3–5.9)	0.73
Age +1 vs age	0.9 (0.9–1.0)	0.02
Married/partnered vs not	0.09 (0.02–0.5)	0.004
1-Month increase in time on therapya	1.2 (0.8–1.5)	0.29

Notes:

a Indicates a one-unit increase in the respective continuous scale; N=70.

Abbreviations: CI, confidence interval; HS, high school; OR, odds ratio; PHQ9C, Patient Health Questionnaire 9 continuous; SDS-15, 15-item Symptom Distress Scale.

Figure 1 Classification tree: significant partitioning predictive of adherence.

Note: N=70.
Abbreviations: CR, classification rate; med, medium; SDS-15, 15-item Symptom Distress Scale.