Determinants of hospital utilization: the content of medical inpatient care in Israel.

BACKGROUND

The increasing utilization of general internal medicine hospital wards in Israel during the last decade is a source of concern for health policy makers.

OBJECTIVES

To report on the distribution of selected main and secondary diagnoses among GIM inpatients, and to estimate the proportion of disorders for which appropriate care in the community will reduce the need for hospital admissions and re-admissions.

METHODS

Data from the Health Information and Computer Services of the Israel Ministry of Health (national hospitalization database) for a one year period were analyzed by distribution of diagnostic entities (ICD-9-CM) in GIM and in medical subspecialty wards.

RESULTS

Of the 313,824 discharges from hospital divisions of medicine in 1995, 256,956 (81.9%) were from GIM and 56,868 (18.1%) from specialty wards. Main and secondary discharge diagnoses were available for 188,807 GIM and 35,992 specialty patients. Of all main diagnoses in GIM wards, 27% were coded as "general or systemic symptoms and signs" or as "abnormal laboratory or ill defined manifestations" (ICD-9-CM codes 780-799, 276,277), and heart diseases comprised another 27%. The remaining main diagnoses covered almost all medical conditions. The combined proportion of "ambulatory care sensitive hospital admissions" (bronchial asthma, hypertension, congestive heart failure, chronic obstructive pulmonary disease, diabetes) constituted 12% of all main diagnoses in GIM, and respiratory symptoms or signs comprised another 11%. A by-product of this analysis was an insight into the experience of undergraduate medical students in GIM.

CONCLUSIONS

Assuming that 12-75% of admissions for "ambulatory care sensitive disorders" are preventable, an improved review before hospital discharge and a closer outpatient follow-up may reduce the load on GIM wards by 1-17%. This wide range justifies controlled trials to determine the effect of improved community care on hospital utilization. GIM wards offer valuable learning opportunities, but they cannot be a substitute for primary care clinics. The unexplained high proportion of GIM inpatients who were discharged with an unspecified main diagnosis could be detrimental for the accuracy of hospitalization statistics, and justifies investigation by chart audits into physicians' habits of documentation.