Factors influencing inpatient mortality of medical patients

ABSTRACT

OBJECTIVE: To investigate factors influencing inpatient mortality and length of stay among medical patients at a public hospital. METHODS: A case-control study involving a 10 percent sample of medical admissions who died (n=109) was done at the Kingston Regional Hospital during 1998. These were matched for age, gender and admission date to 2 controls (n=180) where death did not occur. Trained personnel abstracted information from personnel records. RESULTS: The sample comprised 147 men and 139 women of mean/Standard Deviation (SD) age 61.3ñ18.1 years and range of 12 to 94 years. The mean/SD length of stay was 6.3ñ6.0 days with a median of 5 days. Length of stay did not differ by gender (p=0.69) or mortality (p=0.86). Re-admission accounted for 34.3 percent of admissions occuring at a median of 174 days. There was 70 percent agreement between the provisional diagnosis at admission and the primary discharge diagnosis. The commonest primary diagnoses were diabetes mellitus and hypertension (14 percent each). Stroke, pneumonia and cancer each accounted for over 5 percent of primary diagnoses. Risk of death was greater in women who were alone (single or widowed/divorced/separated) than in those in a union - odds ratio (OR) and 95 percent confidence interval (95 percent CI) 3.63 (1.36, 9.67). In men the OR (95 percent CI) was 0.94 (0.38-2.31). Cancer, stroke chronic renal failure and pneumonia were associated with an increased risk of in-hospital mortality and so was documentation of examination by a consultant. There was an inverse association between the number of entries per day in patients' notes and the risk of death. Less than 2 percent of admissions had a record of patient satisfaction. Nurses notes were judged to be adequate in 76.5 percent of admissions but only 19.2 percent of patient records were rated as good overall. Good quality records were not associated with better survival or shorter hospitalization. CONCLUSION: The relationship between process of care and inpatient mortality is complex and clear associations were not demonstrated for overall mortality. Cause-specific mortality may be a more informative outcome for quality of care studies. (AU)