Abstract P185: Self-Reported Medication Adherence in 14,246 Patients with Atrial Fibrillation from the ATRIA2-CVRN Study
Authors: Black Mary Helen , Fang Margaret C , Singer Daniel E , Go Alan S , Reynolds Kristi 
Published: July 2021

Background:
Although anticoagulation therapy has been shown to significantly reduce risk of stroke in patients with atrial fibrillation (AF), adherence to prescribed therapy is challenging. Few studies have investigated the demographic, behavioral and clinical factors associated with medication adherence in this population.

Methods:
We examined associations between these characteristics and self-reported medication adherence in a large, ethnically diverse cohort of patients with incident diagnosed AF from Kaiser Permanente Northern and Southern California. Medication non-adherence was defined as self-report of any one of the following during the past month: taking medications as prescribed < 75% of the time, forgetting to take one or more prescribed medications > once per week, or deciding to skip one or more prescribed medications > once per week.

Results:
Among 14,246 survey respondents (43% female; 6% Black, 8% Hispanic, 7% API), 956 (7%) were non-adherent by self-report. Mean age ± SD was 72 ± 12 yrs; 26% were <65 yrs old. In a multivariable model (Table), participants <65 yrs old were 74% more likely (OR 95% CI: 1.50-2.00) to be non-adherent that those >65. Ethnic minorities and patients having low household income were also more likely to be non-adherent. Patients who reported having poorer general health and greater memory decline over the past 2-3 yrs had higher odds of reporting non-adherence to their medications, particularly among those who forgot to take prescribed medications > once per week. Patients who were prescribed warfarin during the 1 yr prior to survey completion were 44% less likely to be non-adherent by self-report (OR 95% CI: 0.49-0.64).

Conclusions:
In this large AF population, younger age, race/ethnicity, lower income, and perception of poor general health and declining memory were associated with increased odds of self-reported non-adherence to medications, while warfarin use was associated with decreased likelihood of non-adherence.

Adjusted Odds Ratios (OR) and Confidence Intervals (95% CI) from Multivariable Logistic Regression Model of Self-Reported Medication Adherence

Non-adherent (n=956) vs. Adherent (n=13,290)
p-value

Age [yrs]

< 65
1.60 (1.38, 1.85)
< 0.0001

> 65
Referent

Sex

Female
Referent

Male
1.12 (0.97, 1.29)
0.12

Race/Ethnicity

non-Hispanic White (NHW)
Referent

Asian/Pacific Islander (API)
1.47 (1.15, 1.88)
0.002

Black
2.06 (1.63, 2.60)
< 0.0001

Hispanic
1.39 (1.10, 1.74)
0.005

Other/Missing
1.32 (1.00, 1.75)
0.053

Income

< 25,000
1.32 (1.10, 1.58)
0.004

> 25,000
Referent

Missing/Unknown
0.96 (0.81, 1.14)
0.676

Marital Status

Married
Referent

Not Married
1.28 (1.11, 1.48)
0.0009

Missing/Unknown
1.03 (0.54, 1.97)
0.933

General Health

Poor
1.30 (1.02, 1.66)
0.032

> Fair
Referent

Missing/Unknown
1.16 (0.60, 2.23)
0.664

Memory Decline

Yes
1.66 (1.44, 1.92)
< 0.0001

No
Referent

Don't Know
1.30 (1.01, 1.68)
0.038

Missing/Unknown
1.55 (1.01, 2.38)
0.044

Warfarin Use

Yes
0.56 (0.49, 0.64)
< 0.0001

No
Referent