Aims:
Katz index* assesses independancy of a person in performing activities of daily living (bathing, dressing, toileting, transfering, continence, feeding). We evaluated the use of Katz index for the prediction of inadequate bowel preparation among inpatients undergoing colonoscopy.
Methods:
Post-hoc analysis of the data from a cohort inpatients undergoing colonoscopy in 4 tertiary Greek centers. To calculate Katz index each of the aforementioned domains scores 1 point if patient performs the respective activity independantly (range 0 – 6; higher value indicates higher independancy level). We used the Area Under the Curve (AUROC) to determine Katz index discriminative ability to predict inadequate bowel prep.
Results:
Out of 261 patients (100 bedridden, 140 men, 70.7 ± 15.4 years old) 89 (34,1%) had inadequate bowel preparation (BBPS< 6). Katz index was higher among ambulatory compared to bedridden patients (p < 0.0001), but it did not differ between individuals with adequate and inadequate bowel preparation (p = 0.08). Katz index showed a low discriminative ability to predict inpatients with inadequate bowel preparation not only in the entire cohort [AUROC (95% CI)= 0.44 (0.36 – 0.52), p = 0.11 but also in the groups of ambulatory and bedridden patients [AUROC (95% CI)= 0.50 (0.39 – 0.60), p = 0.9 and 0.55 (0.43 – 0.67), p = 0.4 respectively].
Conclusions:
Katz index failed to predict satisfactorily inpatients (either ambulatory or bedridden) with inadequate bowel preparation before colonoscopy.
*Katz, S, et al. Progress in the development of the index of ADL. The Gerontologist; 1970;10, 20 – 30.
