The impact of weight and weight loss on clinical outcomes of hospital inpatients

Abstract

An increase in worldwide obesity has led to much research into the health of the overweight and obese human population. Obesity is caused by many factors including poor dietary intake, stress and an increase in physical inactivity and has been found to cause multiple complications including cardiovascular diseases, some cancers, kidney diseases and musculoskeletal issues. Research involving hospital admissions of overweight and obese individuals has shown that there are uncertainties as to whether poorer hospital outcomes occur. The obesity paradox has also been demonstrated with lower mortality rates observed in patients who are obese or overweight with conditions including cardiovascular disease, diabetes and chronic obstructive pulmonary disease. The primary aims of this thesis were to determine whether morbid obesity (≥40kg/m2) was associated with a longer inpatient length of stay and whether weight loss between hospital admissions (more than 30 days from discharge to readmission) showed altered health outcomes from those who did not have any significant weight change. This research has demonstrated an increased length of stay in the morbidly obese which remained after adjusting for confounders including comorbidity, socioeconomic status and ethnicity. Weight loss was associated with poorer hospital outcomes (longer length of stay, longer length of stay in the intensive care unit (if admitted) and higher mortality) regardless of initial body mass index both during and after an unplanned hospital readmission.