Influence of patient-assessed quality of chronic illness care and patient activation on health-related quality of life.

OBJECTIVE To examine the association of the Patient Assessment of Chronic Illness Care (PACIC) with health-related quality of life (HRQoL) and the modulating effect of patient activation on this association. DESIGN AND PARTICIPANTS A population-based prospective cohort study of people with Type 2 diabetes in Queensland, Australia, using data from self-report questionnaires, collected annually from 2008 (n = 3761) to 2010 (n = 3040). MAIN OUTCOME MEASURES Predictors were the 20-item PACIC (dichotomized at the score of 3), and the 13-item Patient Activation Measure (PAM), dichotomized into activation Levels 1 and 2 versus Levels 3 and 4. Analyses were restricted to participants whose PACIC and PAM categories did not change over 2 years of follow-up. Outcome variables were EQ-5D index and EQ VAS dichotomized at the uppermost quartile, and EQ-5D index also dichotomized at the median. STATISTICAL ANALYSES An inverse probability weighted Poisson regression with a log-link function and a binary response variable for each outcome was used to obtain risk ratios (RRs), and the interaction between PACIC and PAM was statistically modelled, taking into consideration patient characteristics and the respective baseline outcome variable. RESULTS The positive association between the PACIC and EQ VAS was seen only in participants with low activation (adjusted RR: 3.91; 95% CI: 1.40-10.95; P = 0.009), and not in those with high activation, indicating the non-synergistic interaction effect of the PACIC and PAM. This association was not found with EQ-5D index. CONCLUSIONS Chronic care received consistently over time can positively affect health status, and benefit patients with low activation.