Accuracy of self-reported weight in a high risk geriatric population in the emergency department

Weight is important information in the emergency department (ED). Weight loss leads to an increase of mortality and is suggestive of morbidity. Correct weight is important for dosing of drugs to avoid toxicity and lack of effectiveness. Objective body weight measurement is often not possible in the emergency department. Especially in elderly ED patients, acute disease might have an impact on weight reporting. The objective of this study was to determine whether body weight reported by elderly patients presenting to the ED with non-specific symptoms is accurate.

In 233 patients, measured weight was detected within patients' medical record and was compared to reported weight at presentation in the ED.

The median age of the observed population was 74 years (IQR 72, 86). Comparison between estimated and measured weight showed a good agreement between the two measures (Pearson's correlation coefficient r = 0.94). The mean difference between estimated and measured weight was small (+0.1 kg) whereas the range of the estimation error was between -10.9 and 11.1 kg. Age had no influence on the accuracy to predict the measured weight. Also, the correlation did not differ in patients with and without acute morbidity or between men and women.

Neither old age nor acute disease status impaired the strong correlation of reported and measured weight. Therefore, self reported weight can be used as approximation for real body weight in elderly ED patients presenting with non-specific complaints.