Impact of elevated BMI and types of comorbid conditions on health-related quality of life in a nationally representative US sample

Abstract

Objective: Elevated BMI is associated with multiple chronic conditions including diabetes and CVD. Patients with overweight or obesity may also suffer from comorbidities not directly related to the pathophysiology of elevated BMI. The current study sought to determine the impact of BMI and different types of chronic conditions on health-related quality of life (HRQoL) outcomes. Design: Six weight categories by BMI were identified: underweight, normal weight, overweight, Class-I obesity, Class-II obesity and Class-III obesity. Twenty chronic conditions were considered and categorised as elevated BMI-related (concordant) or -unrelated (discordant) conditions. HRQoL outcomes were measured using Short Form-6 Dimensions (SF-6D). Multivariable regression models were performed to examine the impact of type, number of comorbid conditions and BMI categories on SF-6D scores. Setting: Medical Expenditure Panel Survey (2013-2015). Participants: Nationally representative sample of US population; 18 years or older (n 58 960). Results: Of the sample, 1·7 %, 32·9 %, 34·0 % and 31·4 % were classified as underweight, normal weight, overweight and obese, respectively. The SF-6D scores were significantly decreased across all obesity classes, with the largest reduction in Class-III obesity (0·033; P < 0·001). Additionally, individuals with obesity having one or more concordant or discordant comorbidities further reduced SF-6D scores between 0·031 and 0·148 (P-values < 0·001) or between 0·080 and 0·212 (P-values < 0·001), respectively. Conclusions: Individuals with obesity had a significant reduction in HRQoL outcomes compared to those with normal BMI. Importantly, discordant comorbidity resulted in greater reduction in HRQoL outcomes compared to concordant comorbidity in subjects with elevated BMI.