Associations of Medication Regimen Complexity with COPD Medication Adherence and Control

Figures & data

Table 1 Baseline Characteristics of Study Population, N=400

	N (%)
Age, mean years (SD)	68.8 (8.7)
Age Category
50–59	63 (15.8)
60–69	149 (37.3)
70–79	139 (34.8)
80+	49 (12.3)
Male Sex	155 (38.8)
Race and ethnicity
White, non-Hispanic	162 (40.9)
Black, non-Hispanic	139 (35.1)
Hispanic	66 (16.7)
Other	29 (7.3)
Education
High school or less	63 (15.9)
High school graduate	88 (22.2)
Some college	117 (29.5)
College graduate	129 (32.5)
English Proficiency, good-excellent	334 (84.1)
Low health literacy	93 (23.5)
Insurance
Medicare + Medicaid	98 (24.7)
Medicaid or self-pay	51 (13.4)
Medicare	47 (11.8)
Private	199 (50.1)
Comorbidities, by chart documentation
Hypertension	386 (96.7)
Diabetes mellitus	144 (36.2)
Depression (n=363)	61 (16.8)
Impairment of executive function (n=366)	46 (12.6)
Number of prescribed medications, mean (SD)	11.9 (4.9)

Abbreviations: MRCI, medication regimen complexity index; COPD, chronic obstructive pulmonary disease.

Table 2 Association of MRCI Scores and Medication Counts with COPD, Hypertension, and Diabetes Medication Adherence

	COPD Medication (Self-Report)		COPD Medication (Dose Count)		Hypertension Medication (Self-Report)		Diabetes Medication (Self-Report)
	Low	Adequate	Low	Adequate	Low	Adequate	Low	Adequate
N (%)	175 (45.0)	214 (55.0)	172 (52.6)	155 (47.4)	110 (28.9)	270 (71.1)	47 (38.8)	74 (61.2)
MRCI, mean (sd)	33.5 (13.4)	32.0 (14.8)	32.7 (13.6)	31.5 (13.6)	32.6 (13.5)	32.8 (14.8)	39.1 (14.4)	38.3 (15.7)
# Medications, mean (sd)	11.7 (4.5)	12.0 (5.0)	11.8 (4.7)	12.0 (4.7)	11.0 (4.0)	12.3 (5.2)*	13.0 (4.2)	14.9 (5.2)*
MRCI, %
1^st quartile (5–22)	24.0	23.8	19.8	28.4	26.4	24.1	13.0	14.1
2^nd quartile (23–30)	21.1	29.9	29.1	25.2	25.5	25.6	21.7	16.9
3^rd quartile (31–42)	25.1	24.8	25.6	23.9	19.1	25.9	17.4	28.2
4^th quartile (43–82)	29.7	21.5	25.6	22.6	29.1	24.4	47.8	40.9
# Medications, %
1^st quartile (2–8)	28.6	24.3	27.9	21.9	28.2	26.3	15.2	9.9
2^nd quartile (9–11)	23.4	26.6	20.9	31.6	30.0	22.6	21.7	18.3
3^rd quartile (12–15)	28.0	25.7	31.4	25.2	28.2	25.2	37.0	25.4
4^th quartile (16–29)	20.0	23.4	19.8	21.3	13.6	25.9	26.0	46.5

Note: *P <0.05.

Abbreviations: MRCI, medication regimen complexity index; COPD, chronic obstructive pulmonary disease.

Table 3 Univariate Associations of MRCI Scores and Medication Counts with COPD Severity, and Hypertension and Diabetes Control

	COPD Severity Score		MRC Dyspnea Scale		Blood Pressure		Hemoglobin A1c
	≤ 1 SD Above Mean	> 1 SD Above Mean	Levels 1–3	Levels 4–5	At Target	Above Target	<8.0%	≥8.0%
N (%)	313 (78.3)	87 (21.8)	120 (34.1)	232 (65.9)	220 (57.3)	164 (42.7)	96 (74.4)	33 (25.6)
MRCI, mean (sd)	31.2 (13.8)	38.8 (14.6)^§	30.1 (12.6)	35.7 (14.7)^‡	34.5 (14.9)	33.3 (13.6)	38.1 (14.3)	41.4 (16.4)
MRCI, %
1^st quartile	26.2	14.9^§	29.2	16.8^†	21.3	25.5	15.2	10.4
2^nd quartile	28.1	16.1	24.2	27.2	26.8	25.5	9.1	24.0
3^rd quartile	24.6	25.3	28.3	24.1	23.8	25.0	24.2	28.1
4^th quartile	21.1	43.7	18.3	31.9	28.1	24.1	51.5	27.5
Medication count, mean (sd)	14.2 (5.3)	11.6 (4.7) ^‡	12.6 (5.0)	10.9 (4.5)^†	12.0 (5.1)	11.8 (4.5)	13.9 (5.2)	14.5 (4.4)
Medication count, %
1^st quartile (2–8)	12.2	28.2*	22.4	34.2*	26.8	26.2	14.6	9.1
2^nd quartile (9–11)	18.4	25.9	24.6	24.2	23.6	26.8	21.9	15.2
3^rd quartile (12–15)	34.7	25.1	26.7	25.8	25.9	26.8	24.0	39.4
4^th quartile (16–29)	34.7	20.8	26.3	15.8	23.6	20.1	39.6	36.4

Note: *P<0.05, ^†P<0.01, ^‡P<0.001, ^§P<0.0001.

Abbreviations: MRCI, medication regimen complexity index; COPD, chronic obstructive pulmonary disease; MRC, Medical Research Council.

Table 4 Multivariate Associations of MRCI Count with COPD Severity, and Hypertension and Diabetes Control

	High COPD Severity Score*		High MRC Dyspnea Scale Score^†		Blood Pressure Not at Target		Hemoglobin A1c ≥8.0%
	OR (95% CI)	P	OR (95% CI)	P	OR (95% CI)	P	OR (95% CI)	P
MCRI
1^st quartile	Ref.		Ref.		Ref.		Ref.
2^nd quartile	1.33 (0.33–5.41)	0.69	1.86 (0.89–3.89)	0.10	0.78 (0.41–1.50)	0.46	0.35 (0.05–2.71)	0.31
3^rd quartile	2.58 (0.70–9.43)	0.15	1.35 (0.64–2.85)	0.44	1.02 (0.52–2.00)	0.95	1.25 (0.18–8.82)	0.82
4^th quartile	5.00 (1.46–17.1)	0.01	2.27 (1.03–5.03)	0.04	0.67 (0.34–1.35)	0.26	1.50 (0.22–10.2)	0.68
Age Category
50-59	Ref.		Ref.		Ref.		Ref.
60-69	1.67 (0.57-4.92)	0.35	0.78 (0.35-1.83)	0.57	2.49 (1.23-5.03)	0.01	1.17 (0.29-4.76)	0.82
70-79	1.43 (0.44-4.70)	0.55	0.85 (0.35-2.05)	0.72	1.40 (0.68-2.89)	0.36	0.09 (0.01-0.75)	0.03
80+	1.42 (0.33-8.94)	0.52	2.19 (0.74-6.46)	0.16	0.67 (0.26-1.72)	0.41	1.69 (0.19-15.1)	0.64
Male Sex	1.48 (0.66–3.33)	0.34	1.24 (0.71–2.16)	0.46	0.81 (0.50–1.33)	0.41	0.64 (0.18–2.33)	0.51
Race and ethnicity
White, non-Hispanic	Ref.		Ref.		Ref.		Ref.
Black, non-Hispanic	1.63 (0.55–4.87)	0.38	2.71 (1.27–5.82)	0.01	0.75 (0.39–1.45)	0.39	1.19 (0.20–7.18)	0.85
Hispanic	1.42 (0.36–5.66)	0.62	3.02 (0.98–9.33)	0.05	1.49 (0.59–3.73)	0.40	1.54 (0.23–10.5)	0.66
Education
College graduate	Ref.		Ref.		Ref.		Ref.
Some college	1.35 (0.45–4.06)	0.60	1.05 (0.54–2.05)	0.88	0.92 (0.49–1.73)	0.80	1.81 (0.30–11.1)	0.52
High school graduate	2.66 (0.85–8.30)	0.09	1.22 (0.56–2.66)	0.62	0.49 (0.29–1.17)	0.13	1.11 (0.14–8.63)	0.92
Did not graduate high school	0.17 (0.02–1.70)	0.13	1.44 (0.44–4.76)	0.55	0.80 (0.32–2.05)	0.65	4.62 (0.46–46.0)	0.19
English proficiency, low	0.78 (0.07–8.76)	0.84	-		0.30 (0.07–1.28)	0.10	1.62 (0.13–20.8)	0.71
Low health literacy	0.88 (0.32–2.41)	0.81	1.46 (0.64–3.33)	0.36	0.97 (0.50–1.89)	0.92	1.23 (0.29–5.25)	0.78
Insurance
Private	Ref.		Ref.		Ref.		Ref.
Any Medicaid	3.44 (1.19–9.94)	0.02	1.87 (0.83–4.22)	0.13	1.08 (0.54–2.15)	0.83	1.05 (0.20–5.48)	0.95
Medicare	0.80 (0.18–3.52)	0.77	1.73 (0.72–4.17)	0.22	1.63 (0.75–3.55)	0.22	1.90 (0.23–15.7)	0.55
Depression	2.61 (1.05–6.47)	0.04	2.36 (1.04–5.31)	0.04	0.59 (0.30–1.17)	0.13	0.50 (0.10–2.39)	0.38
Executive function impairment	0.67 (0.17–2.68)	0.57	0.96 (0.35–2.66)	0.94	0.77 (0.35–1.69)	0.51	2.99 (0.46–19.4)	0.25

Notes: *COPD severity score >1 standard deviation above the mean value for the study sample. ^†MRC Dyspnea Scale score >3.

Abbreviations: COPD, chronic obstructive pulmonary disease; MRC, Medical Research Council; MRCI, medication regimen complexity index.

Table 5 Multivariate Associations of Medication Count with COPD Severity and Hypertension Control

	High COPD Severity Score*		High MRC Dyspnea Scale Score^†		Blood Pressure Not at Target
	OR (95% CI)	P	OR (95% CI)	P	OR (95% CI)	P
Medication count
1^st quartile	Ref.		Ref.		Ref.
2^nd quartile	1.80 (0.53–6.14)	0.35	1.40 (0.67–2.93)	0.73	0.92 (0.48–1.77)	0.81
3^rd quartile	2.38 (0.74–7.73)	0.15	1.65 (0.80–3.40)	0.17	0.97 (0.51–1.83)	0.92
4^th quartile	3.22 (0.94–11.0)	0.06	2.90 (1.31–6.37)	0.009	1.43 (0.71–2.89)	0.32

Notes: Analyses adjusted for age, sex, race and ethnicity, education, English language proficiency, level of health literacy, insurance, depression and cognitive impairment. Model for hemoglobin A1c did not converge. *COPD severity score >1 standard deviation above the mean value for the study sample. ^†MRC Dyspnea Scale score >3

Abbreviations: COPD, chronic obstructive pulmonary disease; MRC, Medical Research Council; MRCI, medication regimen complexity index.