Background/Aims: Recent studies have indicated that despite the protective effect of overweight/obesity on mortality in older patients, a dual diagnosis of obesity and malnutrition worsens outcomes. This study aimed to investigate whether obese patients aged 65yrs and over with a concurrent diagnosis of malnutrition have different clinical outcomes to their non-malnourished, obese peers.
Methods: A retrospective sample of patients admitted to The Prince Charles Hospital included in the Nutrition and Dietetics Malnutrition Annual Audit Database between January 2011 and December 2019 was reviewed. Univariate and logistic regression analyses were undertaken to investigate the relationship between demographics and outcome measures (12-month mortality, prolonged length of stay and representation for hospital care within 12 months). Obesity was defined as BMI >30kg/m2; malnutrition was defined by Subjective Global Assessment (SGA) category B/C.
Results: 326 obese patients aged 65yrs and over admitted to medical wards were included in the final analyses. Median patient age was 76.1yrs, with 51.8% female. 11% of the cohort were malnourished as well as obese. Median BMI was 32.9kg/m2. Malnutrition increased the risk of 12-month mortality (OR:2.8, 95% CI 1.36-5.77, p=0.005), prolonged length of stay (OR:3.18, 95% CI 1.53-6.63, p=0.002) and very prolonged length of stay (OR:3.86, 95% CI 1.78-8.35, p=<0.001). Malnutrition was not associated with a significantly increased number of presentations for hospital care within 12 months (p=0.531).
Conclusion: Older patients with a dual diagnosis of obesity and malnutrition have significantly worse outcomes than their obese but non-malnourished peers. Obesity should not preclude the assessment of nutritional status in older hospitalized adult patients.