The obesity paradox: An analysis of pre-procedure weight trajectory on survival outcomes in patients undergoing transcatheter aortic valve implantation

Obesity and Transcatheter Aortic Valve Replacement

Amidst an aging population and escalating obesity prevalence, elucidating the impact of obesity on transcatheter aortic valve replacement (TAVR) outcomes becomes paramount. The so-called "obesity paradox"-a term denoting the counterintuitive association of obesity, typically a risk factor for cardiovascular diseases, with improved survival outcomes in TAVR patients relative to their leaner or normal-weight counterparts-merits rigorous examination. This review comprehensively investigates the complex relationship between obesity and the clinical outcomes associated with TAVR, with a specific focus on mortality and periprocedural complications. This study aims to deepen our understanding of obesity's role in TAVR and the underlying mechanisms of the obesity paradox, thereby optimizing management strategies for this patient demographic, tailored to their unique physiological and metabolic profiles.

The Obesity Paradox and Mortality in Older Adults: A Systematic Review

“Obesity paradox” describes the counterintuitive finding that aged overweight and obese people with a particular disease may have better outcomes than their normal weight or underweight counterparts. This systematic review was performed to summarize the publications related to the obesity paradox in older adults, to gain an in-depth understanding of this phenomenon. PubMed©, Embase©, and Scopus© were used to perform literature search for all publications up to 20 March 2022. Studies were included if they reported data from older adults on the relation between BMI and mortality. The following article types were excluded from the study: reviews, editorials, correspondence, and case reports and case series. Publication year, study setting, medical condition, study design, sample size, age, and outcome(s) were extracted. This review has been registered with PROSPERO (no. CRD42021289015). Overall, 2226 studies were identified, of which 58 were included in this systematic review. In all, 20 of the 58 studies included in this review did not find any evidence of an obesity paradox. Of these 20 studies, 16 involved patients with no specific medical condition, 1 involved patients with chronic diseases, and 2 involved patients with type 2 diabetes mellitus. Seven out of the nine studies that looked at short-term mortality found evidence of the obesity paradox. Of the 28 studies that examined longer-term mortality, 15 found evidence of the obesity paradox. In the studies that were conducted in people with a particular medical condition (n = 24), the obesity paradox appeared in 18 cases. Our work supports the existence of an obesity paradox, especially when comorbidities or acute medical problems are present. These findings should help guide strategies for nutritional counselling in older populations.

Effect of BMI on patients undergoing transcatheter aortic valve implantation: A systematic review and meta-analysis

BACKGROUND

The relationship of body mass index (BMI) and an "obesity paradox" with cardiovascular risk prediction is controversial. This systematic review and meta-analysis aims to compare the associations of different BMI ranges on transcatheter aortic valve implantation (TAVI) outcomes.

METHODS

International databases, including PubMed, the Web of Science, and the Cochrane Library, were systematically searched for observational and randomized controlled trial studies investigating TAVI outcomes in any of the four BMI categories: underweight, normal weight, overweight, and obese with one of the predefined outcomes. Primary outcomes were in-hospital, 30-day, and long-term all-cause mortality. Random-effects meta-analysis was performed to calculate the odds ratio (OR) or standardized mean differences (SMD) with 95% confidence interval (CI) for each paired comparison between two of the BMI categories.

RESULTS

A total of 38 studies were included in our analysis, investigating 99,829 patients undergoing TAVI. There was a trend toward higher comorbidities such as hypertension, diabetes, and dyslipidemia in overweight patients and individuals with obesity. Compared with normal-weight, patients with obesity had a lower rate of 30-day mortality (OR 0.42, 95% CI 0.25-0.72, p < 0.01), paravalvular aortic regurgitation (OR 0.63, 95% CI 0.44-0.91, p = 0.01), 1-year mortality (OR 0.48, 95% CI 0.24-0.96, p = 0.04), and long-term mortality (OR 0.69, 95% CI 0.51-0.94, p = 0.02). However, acute kidney injury (OR 1.16, 95% CI 1.04-1.30, p = 0.01) and permanent pacemaker implantation (OR 1.25, 95% CI 1.05-1.50, p = 0.01) odds were higher in patients with obesity. Noteworthy, major vascular complications were significantly higher in underweight patients in comparison with normal weight cases (OR 1.62, 95% CI 1.07-2.46, p = 0.02). In terms of left ventricular ejection fraction (LVEF), patients with obesity had higher post-operative LVEF compared to normal-weight individuals (SMD 0.12, 95% CI 0.02-0.22, p = 0.02).

CONCLUSION

Our results suggest the presence of the "obesity paradox" in TAVI outcomes with higher BMI ranges being associated with lower short- and long-term mortality. BMI can be utilized for risk prediction of patients undergoing TAVI.

Survival benefit of overweight patients undergoing MitraClip® procedure in comparison to normal-weight patients

BACKGROUND

The number of MitraClip® implantations increased significantly in recent years. Data regarding the impact of weight class on survival are sparse.

HYPOTHESIS

We hypothesized that weight class influences survival of patients treated with MitraClip® implantation.

METHODS

We investigated in-hospital, 1-year, 3-year, and long-term survival of patients successfully treated with isolated MitraClip® implantation for mitral valve regurgitation (MR) (June 2010-March 2018). Patients were categorized by weight classes, and the impact of weight classes on survival was analyzed.

RESULTS

Of 617 patients (aged 79.2 years; 47.3% females) treated with MitraClip® implantation (June 2010-March 2018), 12 patients were underweight (2.2%), 220 normal weight (40.1%), 237 overweight (43.2%), and 64 obesity class I (11.7%), 12 class II (2.2%), and 4 class III (0.7%). Preprocedural Logistic EuroScore (21.1 points [IQR 14.0-37.1]; 26.0 [18.5-38.5]; 26.0 [18.4-39.9]; 24.8 [16.8-33.8]; 33.0 [25.9-49.2]; 31.6 [13.1-47.6]; p = .291) was comparable between groups. Weight class had no impact on in-hospital death (0.0%; 4.1%; 1.5%; 0.0%; 7.7%; 0.0%; p = .189), 1-year survival (75.0%; 72.0%; 76.9%; 75.0%; 75.0%; 33.3%; p = .542), and 3-year survival (40.0%; 36.8%; 38.2%; 48.6%; 20.0%; 33.3%; p = .661). Compared to normal weight, underweight (hazard ratio [HR]: 1.35 [95% confidence interval [CI]: 0.65-2.79], p = .419), obesity-class I (HR: 0.93 [95% CI: 0.65-1.34], p = .705), class II (HR: 0.39 [95% CI: 0.12-1.24], p = .112), and class III (HR: 1.28 [95% CI: 0.32-5.21], p = .726) did not affect long-term survival. In contrast, overweight was associated with better survival (HR: 1.32 [95% CI: 1.04-1.68], p = .023).

CONCLUSION

Overweight affected the long-term survival of patients undergoing MitraClip® implantation beneficially compared to normal weight.

A Meta-Analysis on the Impact of High BMI in Patients Undergoing Transcatheter Aortic Valve Replacement

BACKGROUND

A paradoxical association of obesity with lower risk of transcatheter aortic valve replacement (TAVR) outcomes has been reported. We aimed to systematically review the literature and compare TAVR-related morbidity and mortality among individuals with overweight or obesity and their peers with normal body mass index (BMI).

METHODS

PubMed and Embase databases were systematically searched for studies reporting TAVR outcomes in different BMI groups. Separate meta-analyses were conducted for studies reporting hazard ratios (HR) and odds ratios/relative risks. Short- and mid-/long-term outcomes were examined.

RESULTS

26 studies with a total of 74,163 patients were included in our study. Overweight was associated with lower risk of short-term mortality (HR: 0.77; 95% CI: 0.60-0.98) and mid-/long-term mortality (HR: 0.79; 95% CI: 0.70-0.89). Obesity was associated with lower risk for mid-/long-term mortality (HR: 0.79; 95% CI: 0.73-0.86), but no difference was observed in short-term mortality, although a trend was noted (HR: 0.87l 95% CI: 0.74-1.01). Individuals with obesity demonstrated an association with higher odds of major vascular complications (OR: 1.33; 95% CI: 1.05-1.68). Both overweight (OR: 1.16; 95% CI: 1.03-1.30) and obesity (OR: 1.26; 95% CI: 1.06-1.50) were associated with higher likelihood for receiving permanent pacemakers after TAVR.

CONCLUSION

Individuals with overweight and obesity were associated with lower mortality risk compared to those with normal BMI but with higher likelihood of major vascular complications and permanent pacemaker implantation after TAVR.

Cachexia, muscle wasting, and frailty in cardiovascular disease

The last several years have seen increasing interest in understanding cachexia, muscle wasting, and physical frailty across the broad spectrum of patients with cardiovascular illnesses. This interest originally started in the field of heart failure, but has recently been extended to other areas such as atrial fibrillation, coronary artery disease, peripheral artery disease as well as to patients after cardiac surgery or transcatheter aortic valve implantation. Tissue wasting and frailty are prevalent among many of the affected patients. The ageing process itself and concomitant cardiovascular illness decrease lean mass while fat mass is relatively preserved, making elderly patients particularly prone to develop wasting syndromes and frailty. The aim of this review is to provide an overview of the available knowledge of body wasting and physical frailty in patients with cardiovascular illness, particularly focussing on patients with heart failure in whom most of the available data have been gathered. In addition, mechanisms of wasting and possible therapeutic targets are discussed.

Impact of obesity on adverse in-hospital outcomes in patients undergoing percutaneous mitral valve edge-to-edge repair using MitraClip® procedure - Results from the German nationwide inpatient sample

BACKGROUND AND AIM

The number of percutaneous edge-to-edge mitral regurgitation (MR) valve repairs with MitraClip® implantations increased exponentially in recent years. Studies have suggested an obesity survival paradox in patients with cardiovascular diseases. We investigated the influence of obesity on adverse in-hospital outcomes in patients with MitraClip® implantation.

METHODS AND RESULTS

We analyzed data on characteristics of patients and in-hospital outcomes for all percutaneous mitral valve repairs using the edge-to-edge MitraClip®-technique in Germany 2011-2015 stratified for obesity vs. normal-weight/over-weight. The nationwide inpatient sample comprised 13,563 inpatients undergoing MitraClip® implantations. Among them, 1017 (7.5%) patients were coded with obesity. Obese patients were younger (75 vs.77 years,P < 0.001), more often female (45.4% vs.39.5%,P < 0.001), had more often heart failure (87.1% vs.79.2%,P < 0.001) and renal insufficiency (67.0% vs.56.4%,P < 0.001). Obese and non-obese patients were comparable regarding major adverse cardiac and cerebrovascular events (MACCE) and in-hospital death. The combined endpoint of cardio-pulmonary resuscitation (CPR), mechanical ventilation and death was more often reached in non-obese than in obese patients with a trend towards significance (20.6%vs.18.2%,P = 0.066). Obesity was an independent predictor of reduced events regarding the combined endpoint of CPR, mechanical ventilation and death (OR 0.75, 95%CI 0.64-0.89,P < 0.001), but not for reduced in-hospital mortality (P = 0.355) or reduced MACCE rate (P = 0.108). Obesity class III was associated with an elevated risk for pulmonary embolism (OR 5.66, 95%CI 1.35-23.77,P = 0.018).

CONCLUSIONS

We observed an obesity paradox regarding the combined endpoint of CPR, mechanical ventilation and in-hospital death in patients undergoing MitraClip® implantation, but our results failed to confirm an impact of obesity on in-hospital survival or MACCE.

Time to redefine body mass index categories in chronic diseases? Spotlight on obesity paradox

Obesity is a complex condition classically characterised by excessive body fat accumulation and represents one of the most important public health problems worldwide. Although several epidemiological studies have shown that elevated BMI is associated with higher morbidity, and with increased rate of death from all causes and from cardiovascular disease, accumulating evidence suggests that being overweight or obese may be protective (the so-called obesity paradox), at least in chronic diseases. These observations, not only question the validity of the BMI system, but also raise the intriguing question of whether we should redefine what the normal range of BMI is in individuals suffering from a chronic disease. In the present article, we review the available information on the association between elevated BMI and increased morbidity and mortality including obesity-related paradoxes, explore key aspects of the role and limitations of BMI as a measure of increased adiposity and outline potential solutions to address the current controversies regarding the impact of obesity on human health.