<abstract xmlns="http://www.w3.org/1999/xhtml"><sec><h3>Introduction</h3><p>Adherence to treatment recommendations in patients with chronic disease is complex and is influenced by numerous factors. Haemophilia is a chronic disease with reported levels of adherence ranging from 17–82%.</p></sec><sec><h3>Aim</h3><p>Based on the theoretical foundation of the World Health Organization Multidimensional Adherence Model, the objective of this study was to identify the best combination of the variables infusion frequency, annualised bleed rate, age, distance to haemophilia treatment centre (HTC) and Haemophilia Joint Health Score (HJHS), to predict adherence to treatment recommendations in patients with haemophilia A and B on home infusion prophylaxis in Canada.</p></sec><sec><h3>Methods</h3><p>A one-year retrospective cohort study investigated adherence to treatment recommendations using two measures: 1) subjective report via home infusion diaries, and 2) objective report of inventory ordered from Canadian Blood Services. Stepwise regression was performed for both measures.</p></sec><sec><h3>Results</h3><p>Eighty-seven patients with haemophilia A and B, median age 21 years, were included. Adherence for both measures was 81% and 93% respectively. The sample consisted largely of patients performing an infusion frequency of every other day (34%). Median scores on the HJHS was 10.5; annualised bleed rate was two. Distance to the HTC was 51km. Analysis of the objective measure weakly supported greater infusion frequency as a treatment-related factor for the prediction of lower adherence, however the strength of this relationship was not clinically relevant (R2=0.048). For the subjective measure, none of the explanatory variables were significant.</p></sec><sec><h3>Conclusion</h3><p>Adherence is a multifaceted construct. Despite the use of theory, most of the variance in adherence to treatment recommendations in this sample of patients with haemophilia remains unknown. Further research on other potential predictors of adherence, and possible variables and relationships within factors of the MAM is required.</p></sec></abstract>

IntroductionAdherence to treatment recommendations in patients with chronic disease is complex and is influenced by numerous factors. Haemophilia is a chronic disease with reported levels of adherence ranging from 17–82%.AimBased on the theoretical foundation of the World Health Organization Multidimensional Adherence Model, the objective of this study was to identify the best combination of the variables infusion frequency, annualised bleed rate, age, distance to haemophilia treatment centre (HTC) and Haemophilia Joint Health Score (HJHS), to predict adherence to treatment recommendations in patients with haemophilia A and B on home infusion prophylaxis in Canada.MethodsA one-year retrospective cohort study investigated adherence to treatment recommendations using two measures: 1) subjective report via home infusion diaries, and 2) objective report of inventory ordered from Canadian Blood Services. Stepwise regression was performed for both measures.ResultsEighty-seven patients with haemophilia A and B, median age 21 years, were included. Adherence for both measures was 81% and 93% respectively. The sample consisted largely of patients performing an infusion frequency of every other day (34%). Median scores on the HJHS was 10.5; annualised bleed rate was two. Distance to the HTC was 51km. Analysis of the objective measure weakly supported greater infusion frequency as a treatment-related factor for the prediction of lower adherence, however the strength of this relationship was not clinically relevant (R2=0.048). For the subjective measure, none of the explanatory variables were significant.ConclusionAdherence is a multifaceted construct. Despite the use of theory, most of the variance in adherence to treatment recommendations in this sample of patients with haemophilia remains unknown. Further research on other potential predictors of adherence, and possible variables and relationships within factors of the MAM is required.

Predictors of treatment adherence in patients with chronic disease using the Multidimensional Adherence Model: unique considerations for patients with haemophilia

School of Rehabilitation Science, Faculty of Health Science

Department of Health Research Methods, Evidence, and Impact (HEI)

Department of Kenesiology, Faculty of Applied Health Sciences

The Journal of Haemophilia Practice

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

IntroductionAdherence to treatment recommendations in patients with chronic disease is complex and is influenced by numerous factors. Haemophilia is a chronic...

VARIABLE	N	MEAN/SD	MIN/MAX (%)

Objective measure of adherence^†	87	93.55/24.75	0/154%

	N	MEDIAN	1ST & 3RD QUARTILES

Subjective measure of adherence^‡	87	81	51, 98

ABR^§	87	2	0, 4

Age^¶	87	21	10, 36

Distance from HTC^††	87	51	26, 71

HJHS^‡‡	76	10.5	1, 23.5

	CATEGORIES	COUNTS	PERCENTAGE OF SAMPLE

Infusion frequency^§§	1	8	9%
	2	20	23%
	3	21	24%
	4	30	34%
	5	2	2%
	6	1	1%
	7	5	6%

	SUBJECTIVE	OBJECTIVE	HJHS	AGE	FREQUENCY	ABR	DISTANCE
Subjective^‡	1.0000
Objective^†	0.4568	1.0000
HJHS^‡‡	−0.0228	0.0651	1.0000
Age^¶	0.0128	0.0375	0.8573	1.0000
Frequency^§§	0.0402	−0.1959	−0.0250	−0.0351	1.0000
ABR^§	−0.0861	0.0310	0.3438	0.2597	−0.0236	1.0000
Distance^††	0.0977	−0.0307	0.0442	0.0690	−0.0346	0.2038	1.0000

VARIABLE	β-COEFFICIENT	STD ERROR	P-VALUE	95%CI
Frequency	−672.394	324.506	0.041	−1317.599, −27.189
_cons^†	11536.88	1147.566	0.000	9255.207, 13818.54

Predictors of treatment adherence in patients with chronic disease using the Multidimensional Adherence Model: unique considerations for patients with haemophilia

Article Category: Clinical Research

Online veröffentlicht: 25. Juli 2020

Seitenbereich: 92 - 101

DOI: https://doi.org/10.17225/jhp00152

Schlüsselwörter
Treatment adherence and compliance, chronic disease, haemophilia A, haemophilia B, model, theoretical, prophylaxis

© 2020 Karen Strike et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Figure 1

Characteristics of outcome and explanatory variables

Correlation matrixCorrelation co-efficient of the explanatory variables with both measures of adherence

Full model stepwise regression for the objective measure of adherence

Predictors of treatment adherence in patients with chronic disease using the Multidimensional Adherence Model: unique considerations for patients with haemophilia

Article Category: Clinical Research

Online veröffentlicht: 25. Juli 2020

Seitenbereich: 92 - 101

DOI: https://doi.org/10.17225/jhp00152

SchlüsselwörterTreatment adherence and compliance, chronic disease, haemophilia A, haemophilia B, model, theoretical, prophylaxis

© 2020 Karen Strike et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Figure 1

Characteristics of outcome and explanatory variables

Correlation matrixCorrelation co-efficient of the explanatory variables with both measures of adherence

Full model stepwise regression for the objective measure of adherence

Schlüsselwörter
Treatment adherence and compliance, chronic disease, haemophilia A, haemophilia B, model, theoretical, prophylaxis