Stratification of COPD patients by previous admission for targeting of preventative care.

BACKGROUND Hospital admissions for exacerbations of chronic obstructive pulmonary disease (COPD) impact considerably on disease evolution and healthcare provision. Building on previous studies, this study postulated that COPD patients could be stratified by risk of admission to determine which groups provide the greatest burden on resources, and how interventions should be targeted to prevent admissions. METHODS COPD admissions during 1997-2003 in three Strategic Health Authorities in England were analysed (n=80,291). Patients admitted during winter (1 November-31 March) were stratified into three groups according to the number of admissions during the previous year: 0 (NIL), 1-2 (MOD) or >or=3 (FRQ). Winter weeks were classified as "average", "above average", "high", or "very high" risk, compared with the long-term mean. RESULTS The risk of admission during winter for FRQ and MOD patients was 40% and 12% respectively. NIL patients contributed to 70% of winter admissions, and 90% of the variation between "average" and "very high" weeks, versus 9% and 1% for MOD and FRQ. CONCLUSIONS Patients with no previous admissions have lower individual risk, but contribute to a high overall utilisation of health care resources and should be targeted to prevent admissions. Focusing upon high-risk patients (frequent attenders or more severe) may only reduce a small proportion of admissions, and therefore clinicians should ensure that all COPD patients receive appropriate therapy to reduce risk of exacerbations.