A novel decision model to predict the impact of weight management interventions: The Core Obesity Model.

AIMS: Models are needed to quantify the economic implications of obesity in relation to health outcomes and health-related quality of life. This report presents the structure of the Core Obesity Model (COM) and compare its predictions with the UK clinical practice data. MATERIALS AND METHODS: The COM is a Markov, closed-cohort model, which expands on earlier obesity models by including prediabetes as a risk factor for type 2 diabetes (T2D), and sleep apnea and cancer as health outcomes. Selected outcomes predicted by the COM were compared with observed event rates from the Clinical Practice Research Datalink-Hospital Episode Statistics (CPRD-HES) study. The importance of baseline prediabetes prevalence, a factor not taken into account in previous economic models of obesity, was tested in a scenario analysis using data from the 2011 Health Survey of England. RESULTS: Cardiovascular (CV) event rates predicted by the COM were well matched with those in the CPRD-HES study (7.8-8.5 per 1000 patient-years across BMI groups) in both base case and scenario analyses (8.0-9.4 and 8.6-9.9, respectively). Rates of T2D were underpredicted in the base case (1.0-7.6 vs. 2.1-22.7) but increased to match those observed in CPRD-HES for some BMI groups when a prospectively collected prediabetes prevalence was used (2.7-13.1). Mortality rates in the CPRD-HES were consistently higher than the COM predictions, especially in higher BMI groups. CONCLUSIONS: The COM predicts the occurrence of CV events and T2D with a good degree of accuracy, particularly when prediabetes is included in the model, indicating the importance of considering this risk factor in economic models of obesity.

Complication-specific direct medical costs by body mass index for 13 obesity-related complications: a retrospective database study.

BACKGROUND: Obesity, a multifactorial disease associated with many severe complications, affects more than 40% of adults in the United States. OBJECTIVE: To quantify the cost burden of 13 obesity-related complications (ORCs), overall and by body mass index (BMI) class. METHODS: Adult patients (aged ≥ 18 years) with ≥ 1 medical claim with an ICD-9/10 diagnosis code for the ORC of interest were identified using linked data from IQVIA's Ambulatory Electronic Medical Records and PharMetrics Plus. Thirteen ORCs were separately assessed (asthma, dyslipidemia, gastroesophageal reflux disease [GERD], heart failure with preserved ejection fraction [HFpEF], hypertension, musculoskeletal pain, obstructive sleep apnea [OSA], osteoarthritis [OA] of the knee, polycystic ovary syndrome [PCOS], prediabetes, psoriasis, type 2 diabetes mellitus [T2DM], and urinary incontinence); ORC cohorts were not mutually exclusive. For each ORC, the first claim identified for the ORC from January 2010-December 2016 was termed the index date. Patients had continuous enrollment in the 1-year pre-index (without a diagnosis code of the specific ORC under study) and the 1-year post-index, with ≥ 1 BMI value in the 6-months pre-index. Patients with underweight (BMI < 18.5 kg/m2) and those with cancer or pregnancy were excluded. Complication-specific costs were identified as claims with a diagnosis code for the ORC (primary position only for hospitalizations) or ORC-specific medications or procedures. Baseline demographic/clinical characteristics and complication-specific costs over the 1-year follow-up were assessed for each ORC cohort, overall and by BMI class (18.5-24.9; 25.0-29.9; 30.0-34.9; 35.0-39.9; ≥ 40 kg/m2). The association between total complication-specific costs and BMI class was assessed by generalized linear regression model for each ORC, adjusting for baseline characteristics. RESULTS: The total number of patients that comprised the ORC cohorts ranged from 1,275 (HFpEF) to 101,784 (musculoskeletal pain). Across ORC cohorts, 41.6% (musculoskeletal pain) to 73.5% (OSA) had obesity (BMI ≥ 30 kg/m2). For 4 ORC cohorts, more than one fifth of patients had class III obesity (BMI ≥ 40 kg/m2): T2DM, OSA, PCOS, and HFpEF. Baseline mean Charlson Comorbidity Index score increased with increasing BMI class for most ORC cohorts. The most costly ORCs overall based on mean total 1-year cost were: OA of the knee ($3,697 [range from normal weight (BMI: 18.5-24.9 kg/m2) to class III obesity: $2,453-$4,518]), HFpEF ($3,586 [range: $3,402-$4,685]), OSA ($2,768 [$2,442-$2,974]), and psoriasis ($2,711 [$2,131-$3,292]). The highest cost differences (≥20%) were observed among those with class III obesity versus those with normal weight for these aforementioned ORCs, as well as for GERD ($1,719 [$1,484-$1,893]) and asthma ($1,531 [$1,361-$1,780]). Following adjustment, most cost comparisons by BMI class were significantly higher versus those for normal weight for 6 ORCs. CONCLUSIONS: ORCs are important drivers of the economic burden of obesity, indicating an unmet need for the treatment of obesity. Appropriate weight management may reduce ORC-associated costs. DISCLOSURES: This study and its publication were supported by Novo Nordisk. Divino, Anupindi, and DeKoven are employed by IQVIA, which received funding from Novo Nordisk for this study. Ramasamy, Eriksen, Olsen, and Meincke are employed by and shareholders of Novo Nordisk. Material reported in this manuscript was presented in an abstract accepted by the International Society for Pharmacoeconomics and Outcomes Research (ISPOR) 2020, to be published in Value in Health. There was no presentation at ISPOR 2020.

Validation of a new measure of quality of life in obesity trials: Impact of Weight on Quality of Life-Lite Clinical Trials Version.

The Impact of Weight on Quality of Life-Lite (IWQOL-Lite) is widely used in evaluations of weight-loss interventions, including pharmaceutical trials. Because this measure was developed using input from individuals undergoing intensive residential treatment, the IWQOL-Lite may include concepts not relevant to clinical trial populations and may be missing concepts that are relevant to these populations. An alternative version, the IWQOL-Lite Clinical Trials Version (IWQOL-Lite-CT), was developed and validated according to the US Food and Drug Administration's (FDA's) guidance on patient-reported outcomes. Psychometric analyses were conducted to validate the IWQOL-Lite-CT using data from two randomized trials (NCT02453711 and NCT02906930) that included individuals with overweight/obesity, with and without type 2 diabetes. Additional measures included the SF-36, global items, weight and body mass index. The IWQOL-Lite-CT is a 20-item measure with two primary domains (Physical [seven items] and Psychosocial [13 items]). A five-item Physical Function composite and Total score were also supported. Cronbach's alpha and intraclass correlation coefficients exceeded 0.77 at each time point; patterns of construct validity correlations were consistent with hypotheses; and scores demonstrated treatment benefit. The IWQOL-Lite-CT is appropriate for assessing weight-related physical and psychosocial functioning in populations commonly targeted for obesity clinical trials. Qualification from the FDA is being sought for use of the IWQOL-Lite-CT in clinical trials to support product approval and labelling claims.