Predictors of clinical outcome, disease severity, and acuity in hospitalized horses with colic

Colic is known as the most common disease in horses, which can be lethal. The aim of the present study, conducted on 55 horses with colic, was to identify the main potential risk factors for predicting three important clinical variables- namely, clinical outcome (survival), colic severity and colic acuity and to reveal the main subtypes of colic. The potential predictor variables examined included six categories including demographic variables, management variables, clinical variables, gastrointestinal/urinary variables, laboratory variables and ancillary clinical variables. Based on the disease mechanism, the highest frequency was observed for impaction (38%), while the lowest frequency was for torsion (2%). It was also found that the most common anatomical site of colic involvement was the large intestine, while the least common site was liver problems. The frequency of inflammatory colic was slightly higher than that of non-inflammatory colic (51% vs.49%). In addition, the results showed that non-strangulating colic was more common than strangulating colic (76% vs. 24%). Univariate logistic regression analysis indicated that the main predictors of clinical outcome in our study population with colic were CRT (capillary refill time), toxic-line, intestinal motility, WBC, and PCV (Ps < 0.05). In addition, the main predictors of increasing disease severity in univariate ordinal regression analysis were BCS (body condition score), CRT, toxic-line, intestinal motility, anorexia, anuria, albumin, and WBC (Ps < 0.05). Meanwhile, the main predictors of increasing disease acuity were BCS, CRT, toxic-line, and intestinal motility (Ps < 0.05). Our study had limitations including a small sample size, high levels of missing data for some variables (especially laboratory variables), and the lack of a control group without colic. Future studies using larger samples of healthy, normal horses may provide a more realistic and accurate picture of risk factors for predicting clinical outcome and disease severity/acuity.