The research by healthcare analytics firm Lane, Clark & Peacock (LCP), based on a UK real world dataset Discover, shows costs also increased with higher BMI. For example, costs were 64% higher in those with obesity class III (BMI >40 kg/m2) at £1,871 per person per year in 2019 compared to overweight (BMI ≥25-30 kg/m2) at £1,143 per person per year.

Inpatient admissions accounted for the largest share of costs, followed by prescriptions, according to the data.

A second study reveals obesity-related complications multimorbidity was more common with higher BMI, as nearly one in three people living with obesity class III (BMI ≥40 kg/m2) had two or more obesity-related complications compared to one in four of those in the overweight category. Certain high-cost ORCs, such as heart failure and obstructive sleep apnoea, were 3-5 times more common in the highest obesity class. 

Dr Jonathan Pearson-Stuttard, lead author and head of LCP's health analytics team, said: 'Our studies highlight that healthcare costs increase with BMI and are greatest in those living with more severe obesity and those living with common comorbidities such as heart disease, type 2 diabetes and depression.

‘Effective action to control the risk for those living with obesity through holistic weight management as well as prevent obesity onset, prevent progression to more severe obesity and prevent the onset of obesity-related complications could have substantive benefits to patients, healthcare systems and the wider economy.'