Higher medical morbidity burden is associated with external locus of control

To describe the association between an increasing number of coexisting conditions and locus of control (LOC), a psychological construct reflecting the degree to which one perceives circumstances to be controlled by personal actions (internal LOC) versus outside factors (external LOC) in older adults.

Cross-sectional study using survey data from the North Carolina Established Population for Epidemiologic Studies of the Elderly (NC EPESE) data set.

Community.

Three thousand two hundred twelve community-dwelling adults aged 68 and older.

Nine common medical conditions were assessed according to self-report. LOC was measured using a standard questionnaire. Analyses were adjusted for demographics, functional status (self-reported activities of daily living), cognition (Short Portable Mental Status Questionnaire), and depression score (Center for Epidemiologic Studies Depression Scale).

A higher number of chronic conditions was associated with external LOC (β = 0.37, P < .001). This relationship persisted after adjustment for age, race, sex, functional status, cognition, and depression (β = 0.17, P < .001). Most individual conditions were not associated with LOC, although vision impairment (P < .001) and arthritis (P = .02) were associated with more-internal LOC.

These results suggest that medically complex patients tend to exhibit a more-external LOC, meaning that they perceive little personal control over circumstances and environment. Clinicians should be aware of this tendency, because external LOC may impede an older adult's willingness to engage in the considerable task of managing multiple chronic conditions.