Nutrition status and risk factors associated with length of hospital stay for surgical patients

Abstract

Objective: To diagnose the nutrition status of hospitalized patients and identify the risk factors associated with hospital length of stay (LOS).

Methods: The subjective approach and the body mass index (BMI) were used to classify the nutrition status, and other indicators (anthropometry, biochemistry, and energy intake) were analyzed regarding their association with length of hospital stay of 350 patients. The chi-square test was used to compare proportions, and the Mann-Whitney or Kruskal-Wallis test was used to compare continuous measures. Linear association was verified using Spearman's rank correlation coefficient. Cox's regression model was used to investigate factors associated with LOS.

Results: Disease was the factor that influenced LOS the most in the studied population. Longer LOS prevailed in males (P < .0001), patients aged ≥60 years (P = .0008), patients with neoplasms (P < .0001), patients who lost weight during their hospital stay (P < .0001), and malnourished patients (P = .0034). There was a negative and significant, but weak, correlation between LOS and nutrition indicators (calf circumference, arm circumference, triceps skinfold thickness, subscapular skinfold thickness, arm fat area, lymphocyte count, and hemoglobin). Among adults, well-nourished patients were 3 times more likely to be discharged sooner (P = .0002, RR = 3.3 [1.7-6.2]) than those who had some degree of malnutrition. Well-nourished patients with digestive tract diseases (DTD) were also discharged sooner than malnourished patients with the same condition (P = .02, RR = 2.5 [1.1-5.8]). In patients with neoplasms, arm circumference was an independent risk factor to assess LOS (P = .009, RR = 1.1 [1.0-1.1]).

Conclusions: LOS was associated with disease and nutrition status. Among the more common diseases, nutrition status according to the subjective approach determined the LOS for patients with DTD and nutrition status according to arm circumference determined the LOS for patients with neoplasms.