To analyze scores on a scale designed to measure helplessness, a cognitive variable, as a possible mediator of the association between formal education level and mortality over 5 years in patients with rheumatoid arthritis (RA).
A cohort of 1,416 patients with RA from 15 private practices in 6 states and Washington, DC was monitored for over 5 years. Demographic, socioeconomic, therapy, functional status, and psychological variables were analyzed as possible predictors of mortality in invariable and multivariable Cox Proportional Hazards models.
In a 5-year followup, 1,384 patients were accounted for (97.3%), including 174 who died versus 111 expected (standardized mortality ratio = 1.54). Higher mortality was associated significantly with low formal education, high age, poor scores for activities of daily living (ADL) on a modified health assessment questionnaire (MHAQ), and poor scores on a helplessness scale (all P < 0.01) in univariable analyses. High age, few years of formal education, and poor MHAQ ADL scores were all significant independent predictors of mortality when analyzed simultaneously in a Cox Proportional Hazards model. When helplessness scale scores were included in a model, scores greater than 2.4 (on a scale of 1 to 4), higher age, male gender, and increased MHAQ ADL difficulty scores were all independently significantly predictive of 5-year mortality (P < 0.05), while years of education was no longer a significant predictor.
Scores on a helplessness scale appear to mediate a component of the association between formal education level and 5-year mortality in these patients with RA. Health professionals and policy makers might consider interventions directed at modification of helplessness as adjunctive to standard interventions to improve outcomes in RA.