Background Emergency department (ED) crowding is associated with numerous healthcare issues, but little is known about its effect on psychosocial aspects of patient-provider interactions or interpersonal care. We examined whether ED crowding was associated with perceptions of interpersonal care in patients evaluated for acute coronary syndrome (ACS).

Methods Patients presenting to a quaternary academic medical centre ED in New York City for evaluation of suspected ACS were enrolled between November 2013 and December 2016. ED crowding was measured using the ED Work Index (EDWIN), which incorporates patient volume, triage category, physician staffing and bed availability. Patients completed the 18-item Interpersonal Processes of Care (IPC) survey, which assesses communication, patient-centred decision-making and interpersonal style. Regression analyses examined associations between EDWIN and IPC scores, adjusting for demographics, comorbidities and depression.

Results Among 933 included patients, 11% experienced ED overcrowding (EDWIN score >2) at admission, 11% experienced ED overcrowding throughout the ED stay and 30% reported suboptimal interpersonal care (defined as per-item IPC score <5). Higher admission EDWIN score was associated with modestly lower IPC score in both unadjusted (β=–1.70, 95% CI –3.15 to –0.24, p=0.02) and adjusted models (β = –1.77, 95% CI –3.31 to –0.24, p=0.02). EDWIN score averaged over the entire ED stay was not significantly associated with IPC score (unadjusted β=–1.30, 95% CI –3.19 to 0.59, p=0.18; adjusted β=–1.24, 95% CI –3.21 to 0.74, p=0.22).

Conclusion Increased crowding at the time of ED admission was associated with poorer perceptions of interpersonal care among patients with suspected ACS.