Time preference for immediate gratification: Associations with low medication adherence and uncontrolled blood pressure.

Background In search of innovative approaches to the challenge of uncontrolled hypertension, we assessed the association between preference for immediate gratification (i.e., high discounting rate), low medication adherence and uncontrolled blood pressure (BP) in adults with hypertension. Methods Using a probability discounting model and the Collier-Williams hypothetical discount rate framework, participants in this cross-sectional study reported their preference for a smaller amount of money available immediately (high discount rate; immediate gratification preference) versus a larger amount available one year later (low discount rate; delayed gratification preference). Multivariable Poisson regression was used to test the association of high discounting rates with low antihypertensive medication adherence using the validated 4-item Krousel-Wood Medication Adherence Scale (K-Wood-MAS-4 score ≥1). Mediation of the association between high discounting rate and uncontrolled BP (systolic/diastolic BP ≥130/80 mm Hg) by low adherence was tested using the counterfactual approach. Results Among 235 participants (mean age 63.7+/-6.7 years; 51.1% women; 41.9% Black), 50.6% had a high one-year discount rate, 51.9% had low K-Wood-MAS-4 adherence, and 59.6% had uncontrolled BP. High discounting rates were associated with low adherence (adjusted prevalence ratio 1.58, 95% confidence interval (CI) 1.18, 2.12). Forty-three percent (95% CI 40.9%, 45.8%) of the total effect of high discount rate on uncontrolled BP was mediated by low adherence. Conclusions Adults with preference for immediate gratification had worse adherence; low adherence partially mediated the association of high discount rate with uncontrolled BP. These results support preference for immediate gratification as an innovative factor underlying low medication adherence and uncontrolled BP.