Table 3

Relationship between multisystem multimorbidity and mean annual healthcare utilisation† among high-cost VA patients

Number of body systems affected by chronic conditionsnPrimary care visitsSpecialty care visitsMental health visits‡Emergency visitsHospital admissions
130 7723.
254 8374.53.714.91.61.3
366 6105.64.414.51.91.5
453 9376.
530 5097.85.914.62.82.0
612 5669.16.714.23.42.3
Average difference§1.5*0.7*−0.20.4*0.2*
  • *p<0.01.

  • †Predicted annual utilisation rates are generated via multivariate zero-inflated negative binomial regression (for outpatient utilisation) and zero-inflated Poisson regression (for hospital admissions) examining associations between number of systems affected by chronic conditions and utilisation within each domain. All regressions adjust for age, sex, race/ethnicity, marital status, homelessness and insurance status.

  • ‡Among patients with a mental health diagnosis (n=125 962), predicted mental healthcare visits decreased from 32.3 to 20.9 among patients with 1 versus ≥7 body systems affected by chronic conditions, respectively, with an average decrease in 1.9 visits per body system affected by chronic conditions (p<0.01).

  • §Average differences represent change in annual utilisation for each additional system affected by chronic conditions.