The Impact of Obesity-Related Complications on Healthcare Costs – Outcomes of a Pharmacoeconomic Weight Loss Model

Introduction

Obesity pandemic emerges all over the globe outrageously, not only in adults but also in children and adolescents, regardless of socioeconomic status. It is perceived as a significant health problem that pressures healthcare utilization and costs at every level.¹ The report of the World Health Organisation (WHO) declared that 1 billion people will suffer from obesity in 2030 worldwide, with one out of every five women and one out of every seven men.² According to the World Obesity Federation (WOF) forecast, 1.9 billion people will suffer from obesity by 2035, one out of every four individuals.³ Childhood obesity is expected to increase by 100%, and lastly, the economic burden of obesity in the world will be 4.32 trillion dollars in the next decade.⁴

The World Health Organisation European Regional Obesity Report (2022) emphasized that Turkey had been ranked as the first country to have an overweight and obesity rate among all European countries. The mean rate of being overweight was 66.8%, while it was 58.7% in Europe. Regarding statistics on obesity, the mean rate was 32.1% in Turkey and 23.3% in Europe. Regarding gender, the demographics were 64% males and 69.3% overweight individuals in Turkey, higher than the European average of 62.9% males and 54.3% females. The obesity rate was elaborated as 24.4% males and 39.2% women, higher than the European average of 21.8% males and 24.5% females.²

The aforementioned data and the current increase in obesity rate require urgent measures nationwide. The occurrence of comorbidities during obesity is another obstacle to disease management, healthcare utilization, and costs. Obesity, metabolic syndrome, and insulin resistance facilitate inflammation, leading to hypertension, diabetes, cardiac diseases, stroke, respiratory problems, depression, and even various cancers.⁵ Within the scope of this research, we aimed to elucidate the decisive utilization of the “Weight Loss Tool” to model the clinical and economic impacts of selected comorbidities in a specified population and period in private hospitals within nationally adjusted data. This pharmacoeconomic tool aims to assist clinicians and decision-makers in calculating the risks of obesity-related complications over the next ten years. In this study, the impact of obesity on public health was evaluated from the perspective of private health institutions and assessed in terms of financial burden.

Materials and Methods

The “Weight Loss Tool” pharmacoeconomic model was utilized to determine the annual costs of obesity and its ten significant complications from the perspective of private healthcare providers in Turkey. Those obesity-related comorbidities included type 2 diabetes mellitus (T2DM), heart failure, angina, hypertension, atrial fibrillation, hyperlipidemia, sleep apnea, osteoarthritis, asthma, and chronic kidney disease. They were benchmarked from the study of Haase CL et al (2021) on the effect of weight loss on obesity-related outcomes.⁶

A micro-costing approach was used to estimate the direct healthcare costs of 10 obesity-related comorbidities. A survey was conducted among a representative sample of physicians in Turkey to determine healthcare resource utilization rates for comorbidities in the identified cost categories (adverse events, complications, medical devices, diagnostic tests, inpatient procedures, imaging tests, outpatient visits, and drug treatment costs).⁵

CompuGroup Medical (CGM) provided the unit costs of each cost item and obtained them separately for A, B, and C-type private hospitals. Costs in the different categories were obtained by multiplying the unit costs by the health resource utilization rate. The total cost per patient per year of all comorbidities was estimated by summing all cost items in each cost category.

The cost categories in our micro-costing exercise were based on a systematic development process of previously established studies^7,8 (Figure 1). Each item’s cost within each category was calculated separately (Box 1). The quantification of cost categories is denoted in Table 1. The costs were expressed in EUROS (€), and the foreign exchange rate was 1 Euro = 25.9 Turkish Liras (TRY). A Turkish steering committee comprising local academic physicians and a panel of independent industry experts drove local validation of all cost categories (Box 2).

Box 1 Cost Calculation Formulas of the Weight Loss Model

Box 2 Data Validation Procedure for Local Adaptation

Table 1 Specialties Who Contributed Healthcare Resource Utilization Estimates to the Micro-Costing Analysis

Figure 1 (A and B) Identification of cost categories (C) Quantification of cost categories of the model.

Private hospitals are divided into five categories according to the quality of their services, patient rights, and employee safety. The score consists of an evaluation according to statistics such as the square meters of hospital closed area per bed, the number of operating room rooms, the number of nurses per bed, and the number of beds. Three different hospital types were considered when calculating the costs of obesity and its complications. The share of A-type hospitals on private health insurance (PHI) coverage is 75%, B-type hospitals 23%, and C-type hospitals 2%. The main difference between these hospital segmentations can be elaborated on in terms of pricing. According to their pricing strategies, health expenditure that costs 1 unit in a C-segment institution increases 1.44-fold in B-segment and 3-fold in A-segment hospitals.

The weight-loss tool is a pharmacoeconomic model that analyses the economic impact of obesity and obesity-related complications. The model could be adjusted to designate the public and private health costs within specific risk categories.

Results

Obesity-related complications vary according to the private hospital segment. The annual cost of ORCs was 49.181 Euros in C-segment hospitals, 57.817 Euros in B-segment hospitals, and 97.244 Euros in A-segment private hospitals. Hypertension was the lowest-cost complication, with an annual expenditure of 1.325 Euros in C-segment hospitals, 1.544 Euros in B-segment hospitals, and 2.418 Euros in A-segment private hospitals. On the contrary, chronic kidney disease (CKD) had the highest cost, with an annual expenditure of 12.510 Euros in C-segment hospitals, 14.815 Euros in B-segment hospitals, and 24.174 Euros in A-segment private hospitals (Table 2) (Figure 2). While chronic kidney disease, heart failure (HF), and T2DM were the highest costly three complications, hypertension, asthma, and atrial fibrillation were the least costly ORCs.

Table 2 Obesity-Related Costs in Segment A, Segment B, and Segment C Hospitals (The Demographics Data Has Been Calculated According to the Age Distribution of Individuals With Obesity in Turkish Statistical Institute Health Survey Data)

Figure 2 Estimated annual healthcare costs (TRY; 2023) of ORCs in adults with obesity in Turkey According to Hospital Types.

The cost items have been arranged from the highest to the lowest value in all three segments of private hospitals. Obesity-related complications constituted 28.87% of total costs in Segment A hospitals, 29.13% in Segment B hospitals, and 28.54% in Segment C hospitals. The second highest cost item was inpatient procedures, constituting 21.46% of total costs in Segment A hospitals, 17.94% in Segment B hospitals, and 18.23% in Segment C hospitals. The third highest cost item was adverse events, which constituted 17.61% of total costs in Segment A hospitals, 17.77% in Segment B hospitals, and 17.41% in Segment C hospitals. These were followed by monitoring tests as they accounted for 11.20% of total costs in Segment A hospitals, 11.30% in Segment B hospitals, and 11.07% in Segment C hospitals. Outpatient visits were the fifth highest cost, generating 9.55% of total costs in Segment A hospitals, 9.64% in Segment B hospitals, and 9.44% in Segment C hospitals.

Treatment costs and consumable/device costs were the least expensive cost items. Treatment accounted for 3.01% of total costs in Segment A hospitals, 5.06% in Segment B hospitals, and 5.95% in Segment C hospitals, where consumable/device costs were 1.17% of total costs in Segment A hospitals, 1.97% in Segment B hospitals, and 2.31% in Segment C hospitals (Figure 2).

When the obesity-related complications were stratified according to weight loss rate, 5%, 10%, and 20%, a higher cost reduction was observed in the 40–49, 50–59, and 60–69 age groups. It should be noted that this decrease in healthcare expenditure was detected in older age groups (40 to 69) and not in individuals between 20 and 39 years (Table 3).

Table 3 Distribution of Obesity-Related Complication Costs According to Age Stratification in Segment A – B & C Hospitals (The Demographics Data Has Been Calculated According to the Age Distribution of Individuals With Obesity in Turkish Statistical Institute Health Survey Data)

Another analysis of the weight loss rate revealed that the decrease was highest in Type 2 Diabetes Mellitus costs. The effects of weight loss on reducing the cost of obesity-related complications indicated that the highest cost reduction was on T2DM, dyslipidemia, and CKD, respectively. When all cost reduction items were collected, T2DM accounted for 38.54% of the total cost reduction observed with 20% weight loss, 37.6% with 10% weight loss, and 37.15% with 5% weight loss in the 60–69 age group in Segment A hospitals. When the same analysis was performed on the 50–59 age group, T2DM constituted 40.57% of the total cost reduction with 20% weight loss, 41.66% with 10% weight loss, and 41.97% with 5% weight loss. When this calculation was made between the 40–49 age group, 42.66% of the total cost reduction was observed with 20% weight loss, 44.42% with 10% weight loss, and 45.87% with 5% weight loss in T2DM. It has been observed that as patients get younger, T2DM accounts for a larger portion of the costs of all obesity-related complications. In the 30–39 age group, T2DM accounted for 43.57% of the total cost reduction observed with 20% weight loss, 45.25% of the total cost reduction observed with 10% weight loss, and 45.96% of the total cost reduction observed with 5% weight loss. In the youngest patient group (20–29 age group), these rates were 45.57% with 20% weight loss, 46.86% with 10% weight loss, and 47.36% with 5% weight loss. Although the hospital segment has changed, the outcomes were comparable. Regarding the outcomes of our pharmacoeconomic model, when the obesity-related complications were stratified according to weight loss rate, 5%, 10%, and 20%, a higher cost reduction was observed in the 40–49, 50–59, and 60–69 age groups. The effects of weight loss on reducing the cost of obesity-related complications indicated that the highest cost reduction was on T2DM. When all cost reduction items were collected, T2DM accounted for 38.54% of the total cost reduction observed with 20% weight loss, 37.6% with 10% weight loss, and 37.15% with 5% weight loss in the 60–69 age group in Segment A hospitals. When the same analysis was performed on the 50–59 age group, T2DM constituted 40.57% of the total cost reduction with 20% weight loss, 41.66% with 10% weight loss, and 41.97% with 5% weight loss. When this calculation was made between the 40–49 age group, 42.66% of the total cost reduction was observed with 20% weight loss, 44.42% with 10% weight loss, and 45.87% with 5% weight loss in T2DM. It has been observed that as patients get younger, T2DM accounts for a larger portion of the costs of all obesity-related complications. In the 30–39 age group, T2DM accounted for 43.57% of the total cost reduction observed with 20% weight loss, 45.25% of the total cost reduction observed with 10% weight loss, and 45.96% of the total cost reduction observed with 5% weight loss. In the youngest patient group (20–29 age group), these rates were 45.57% with 20% weight loss, 46.86% with 10% weight loss, and 47.36% with 5% weight loss.

Discussion

Apart from its known endocrine and metabolic effects, obesity continues to be investigated as a significant public health problem and emerges with a new complication every day. Many of the clinical and economic impacts of obesity are attributed to comorbidities related to increased mortality.⁹ Obesity increases the risk for over 230 medical conditions, including high blood pressure, heart disease, certain cancers, arthritis, lipid disorders, sleep apnea, and type 2 diabetes. A report by the World Health Organization indicated the effects of obesity on multiple organ systems.¹⁰ Furthermore, observational studies have reported that various conditions, including type 2 diabetes, sleep apnea, osteoarthritis, and cardiovascular disease, are strongly associated with higher BMI. People with obesity tend to have higher direct and indirect healthcare costs. Indirect costs include workers’ compensation, disability costs, and costs of presenteeism and medical-related absenteeism. Better management of obesity can yield significant health and cost savings for the healthcare system.^11–13

According to the results of the “National Burden of Disease Study” conducted by Hacettepe University Population Studies Institute to determine the burden caused by diseases caused by obesity in Turkey, 57.143 people die every year due to diseases and comorbidities caused by obesity. Most of these deaths occur due to ischemic heart disease. On the other hand, the disease with the highest disability burden was determined to be Diabetes.¹⁴ Regarding the outcomes of the Weight Loss Tool, we have found that chronic kidney disease, heart failure, and T2DM were the top 3 costliest complications; hypertension, asthma, and atrial fibrillation were the least expensive ORCs. These results were also similar to the study of Yavuz et al (2023),⁷ where they investigated the ORCs in the public health system. Considering the three aforementioned studies, one can say that the cost items did not change within the last decade.^7,14

In a study conducted to determine the costs of obesity-related surgery in Turkey, obesity costs were divided into pre-surgical, surgical, and post-surgical phases. In the case of surgical treatment of obesity, the most cost is incurred during the surgery phase, while the least cost is seen after the surgery. The cost varies depending on the method used in the surgical treatment of obesity. While the cost for surgeries performed via laparoscopic banding was 3.974 dollars, it was 8.351 dollars for the laparoscopic gastrectomy method and 8.195 dollars for surgeries performed using the laparoscopic gastric bypass method.¹⁵ The Weight Loss Tool was designed to measure ORCs, and therefore, surgery was not included as a separate item; however, the tool indicated that inpatient procedures constituted 21.46% of total costs in Segment A hospitals, 17.94% in Segment B hospitals, and 18.23% in Segment C hospitals. At this stage, it should be emphasized that ORCs constituted 28.87% of total costs in Segment A hospitals, 29.13% in Segment B hospitals, and 28.54% in Segment C hospitals as the leading cost item.

A study from Turkey revealed a concerning trend: as weight increased, so did the costs. The proportion of direct costs arising from obesity in the patient group who underwent surgery with the diagnosis of inguinal hernia, femoral hernia, umbilical hernia, and epigastric hernia was investigated. When total expenses were evaluated, it was determined that there was a 28.81% cost increase for the overweight patient group, 82.97% for the obese, and 210.08% for morbid obese compared to the normal-weight patient group. This significant cost increase for all expenditure types should raise a red flag about the economic impact of obesity. The increase in drug expenditures was 10.75% in the overweight category, 53.09% in obese patients, and 55.28% in morbid obese individuals. The increase in consumable item expenditures was 45.17% in the overweight category, 108.47% in obese patients, and 576.11% in morbid obese individuals. The increase in laboratory expenses was determined to be 77.42% in the overweight category, 1510.14% in obese patients, and 804.61% in morbid obese individuals. The increase in imaging expenditures was 743.75% in the obese category.¹⁶

In another study conducted to determine the cost of obesity in Turkey, the cost of obesity and obesity-related diseases was approximately 4.5 billion dollars in 2004, which increased to 13.5 billion dollars in 2012. Accordingly, there has been an approximately 3-fold increase in the cost of diseases resulting from obesity over the eight years. While the largest share of this cost is in ischemic heart disease, the smallest share is seen in uterine cancer in both periods. According to the “Health Technologies Assessment Report” the economic cost of obesity-related health problems in Turkey was 5 billion dollars in 2004, and it increased to 14 billion dollars in 2012.¹⁷

Weight loss is not just about reducing costs; it’s about gaining health. The greater the weight loss, the greater the health benefits: a 3% decrease can lower blood sugar, a 5% decrease can reduce blood pressure, a 10% decrease can lower the risk of sleep apnea, and a 15% decrease can lead to a significant reduction in cardiovascular events. A median 13% weight loss was associated with significant additional benefits for specific outcomes, notably T2D, CKD, hypertension, and dyslipidemia, compared with maintaining the corresponding stable lower BMI. Metabolic benefits may have conferred weight loss, contributing to additional benefits.^18–20

Nagi et al (2024)²¹ conducted a systematic review of 19 studies conducted using a prevalence-based approach using the Population Attributable Fraction (PAF) methodology. About half of the studies (53%) were conducted in high-income countries, while the others (47%) were conducted in middle-income countries. The economic burden of obesity ranged from a Purchasing power parity (PPP) of 15 million in Brazil to a PPP of 126 billion in the USA in 2022. Direct medical costs comprised 0.7% to 17.8% of the health system expenditure. Furthermore, the total costs of obesity ranged from 0.05% to 2.42% of the country’s gross domestic product (GDP). Of the seven studies that estimated direct and indirect costs, indirect costs accounted for the most considerable portion of five studies.

The World Obesity Federation’s prediction of a 4.3 trillion $ cost by 2035 due to the escalating overweight and obesity crisis underscores the need for comprehensive strategies. These strategies should focus on direct healthcare costs and the indirect toll of lost employment, early retirement, and premature death. The individual, social, and economic cases for investing in obesity prevention and management today to reduce these future costs are evident.²² The OECD’s estimates for the costs are, in turn, derived from the estimated association between high BMI and a range of 38 disease conditions calculated by the Global Burden of Disease Collaboration (GBD, 2017). These 38 conditions cover many of the significant comorbidities of obesity, including hypertension and cardiovascular disease, diabetes, liver and kidney disease, and several other NCDs. However, the list is by no means exhaustive in terms of additional comorbidities associated with high BMI, which are likely to have healthcare costs attached, such as mental health and neurological conditions, endocrine disorders, and respiratory conditions, amongst others, demonstrating the importance of a multi-faceted approach to addressing obesity.²³

As an example, Turkey currently grapples with the highest obesity prevalence among its European counterparts.^3,24 Studies have estimated that obesity and its related comorbidities account for a substantial portion, approximately half, of the country’s total government spending on healthcare.^24–26 This case highlights the significant economic burden that obesity places on healthcare systems, making it a compelling case for investment in prevention and management.

Conclusion

According to the current pharmacoeconomic model, comorbidities were identified as the primary factors contributing to the costs associated with obesity. This study concluded that chronic kidney disease, heart failure, and T2DM were the highest costly three complications, while hypertension, asthma, and atrial fibrillation were the lowest. Weight loss decreased healthcare expenditures significantly in obese patients, and T2DM was the leading cause in all age groups.