Controlling Nutritional Status Score as a Predictor for Chronic Obstructive Pulmonary Disease Exacerbation Risk in Elderly Patients

Abstract

The Controlling Nutritional Status (CONUT) score is a simple screening tool able to assess poor nutritional status as well as to predict clinical adverse outcomes in different clinical settings. No data are available in older patients with chronic obstructive pulmonary disease (COPD). This study aimed to investigate the CONUT score as a predictor of frequent exacerbations. We retrospectively enrolled 222 patients aged 65 years or older, classified in two groups according to the number of exacerbations (or hospitalizations because AECOPD) during the previous year. The two groups were further divided according to low (<5) or high (≥5) CONUT scores. A total of 67.2% of frequent exacerbators had a high CONUT score. These patients exhibited a significantly higher CAT score, lower FEV1 percentage value, and higher prevalence of severe GOLD stages compared to those with low CONUT. Multivariate analysis showed that a CONUT score ≥ 5 was the best independent predictor (OR 20.740, p < 0.001) of the occurrence of ≥2 exacerbations (or 1 hospitalization) during the previous year. The CONUT score seemed to have a high prognostic value for frequent exacerbations for COPD in older patients. The predictive role of different CONUT score cut-off values needs to be validated in larger COPD populations in future multi-center, prospective clinical studies.

Keywords: AECOPD; CONUT score; COPD; elderly; malnutrition.

Figure 1

Flow chart of the study.

Figure 2

Differences in symptoms and respiratory performances in FE groups according to CONUT score. Data are reported as median and IQR values. Abbreviation: CONUT, controlling nutritional status; CAT, COPD assessment test; mMRC, Modified Medical Research Council; FEV1, Forced Expiratory Volume in the first second; IQR, interquartile range. (A) Differences in CAT score between groups according to CONUT score. p = 0.019; (B) Differences in mMRC score between groups according to CONUT score. p = 0.844; (C) Differences in FEV1 percentage value between groups according to CONUT score. p < 0.001. Statistical differences were assessed using Mann–Whitney U Test.

Figure 3

Distribution of severity of GOLD stages between groups according to CONUT score. Abbreviation: CONUT, controlling nutritional status. Statistical differences were assessed using Fisher’s exact test. p < 0.001.

Figure 4

Odds ratios of factors associated with ≥2 exacerbations (or required 1 hospitalization because AOCPD) during previous year in a multivariate logistic regression model applied in the entire cohort studied. Abbreviation: BMI, body mass index; CRP, C reactive protein; CONUT, controlling nutritional status. The asterisk identifies the independent variables that have been found statistically significant.