Table 3.

Direction of association between adherence/persistence and factors

Study	Outcome	Factors			Analysis
		Negative association	Not significant	Positive association
Morgan et al38 UK	Adherence	Longer disease duration	DAS28 score Disease activity and functional disability (high acute-phase reactants HAQ score)	Older age Patients’ awareness of the long-lasting nature of RA Increased belief in medication necessity Lower medications concerns. Increased professional or family member support Increased treatment control	Univariate
Kumar et al27 UK	Adherence	Dissatisfaction with information about csDMARDs (side effects, how do csDMARDs work to control the condition) High concerns about csDMARDs and medication in general (south Asian had more negative views about medicines) South Asians Negative beliefs about csDMARDs and medication in general	IMD score Age Gender Level of education DAS28 score English speaking patients	White British Higher SIMS score	Univariate and multivariate
Gadallah et al28 Egypt	Adherence Rate of prescription refilling Late/on time	High costs of medications Nonavailability of free drugs Experienced side effects of medication Higher disease activity Higher disease duration		Younger age Higher knowledge score Greater general satisfaction score, communication and time spent with doctor Higher beliefs score of the importance and benefits of RA medications	χ2 test Student’s t-test
Salaffi et al30 Italy	Adherence	Low disease activity, older age, higher patient–physician discordance ratings, high number of comorbid conditions	Employment status, educational level, gender, marital status Laboratory parameters and functional data Radiographic data		Logistic regression
Chu et al24 USA	Adherence Treatment abandonment	ETN use, csDMARDs use, knee/joint replacement, age, 65, African Americans, having physical/occupational therapy, corticosteroid use Age, the presence of at least one comorbidity, ETN use, csDMARDs use, knee/joint replacement			Multivariate linear regression
Abdul-Sattar et al32 Egypt	Adherence	Lower educational level, very low and low economic status, rural residency, increased number of medications, higher depressive symptoms	Age, gender, marital status, disease duration		Multiple regression
Glintborg et al36 Denmark	Drug discontinuation	Smoking status (current and previous smokers) statistical significance mainly in men			Univariate multivariate
Højgaard et al37 Denmark	Drug discontinuation	None	Smoking status		Univariate multivariate
Bonafede et al25 USA	Adherence Persistence	Triple therapy (MTX–HCQ–SSZ) Triple therapy (MTX–HCQ–SSZ)			Multiple logistic regression
Hromadkova et al31 Czech Republic	Adherence	Increased QoL (PCS) score for AS patients		Higher HAQ score (higher disability rate) – only for RA patients CQR19 score (continuous and dichotomous variable)	Multivariate logistic regression
Betegnie et al33 France	Adherence	Lower level of pain More than one line of bDMARDs Self-administered bDMARDs Negative belief about treatment Lack of perceived medical and social support	Type of CIRD Gender Experienced side effects		Univariate and multivariate
De Cuyper et al29 Belgium	Adherence	Living alone		Presence of comorbidities Better mental health status	Logistic regression analysis
Lyu et al34 Germany	Persistence		Preindex use of csDMARDs (in the SA and PsA cohorts)	Preindex use of csDMARDs (only in the RA cohort)	Multivariate
Kim et al26 USA	Adherence Persistence	Dual therapy SSZ users	Monotherapy, dual therapy	LEF, MTX users Monotherapy LEF users	ANOVA, χ2, Duncan and t-test
Machado et al35 Brazil	Persistence	csDMARDs use (first and second year) in AS patients		Lower income (first and second year) RA patients Male gender (first year) RA patients Anti-TNF ± csDMARDs users AS patients	Logistic regression

Abbreviations: AS, ankylosing spondylitis; CIRD, chronic inflammatory rheumatic disease; CQR19, 19-item Compliance Questionnaire for Rheumatology; DAS28, Disease Activity Score in 28 joints; bDMARDs, biologic disease-modifying antirheumatic drugs; csDMARDs, conventional synthetic disease-modifying antirheumatic drugs; ETN, etanercept; HAQ, Health Assessment Questionnaire; HCQ, hydroxychloroquine; LEF, leflunomide; IMD, Index of Multiple Deprivation; MARS, Medication Adherence Report Scale; MMAS-8, 8-item Morisky’s Medication Adherence Scale; MEMS, Medication Event Monitoring System; MTX, methotrexate; PCS, Physical Component Scale; PDC, proportion of days covered; PDC*, percentage of days covered; PsA, psoriatic arthritis; QoL, quality of life; RA, rheumatoid arthritis; SD, self-discontinuation; SLE, systemic lupus erythematosus; SIMS, the Satisfaction with Information about Medication Scale; SSZ, sulfasalazine; VAS, Visual Analog Scale.