| Literature DB >> 32079475 |
Rachel C Frank1, Jeff Min1, Mazin Abdelghany1, Samantha Paniagua2,3, Romit Bhattacharya3, Vijeta Bhambhani3, Eugene Pomerantsev3,4, Jennifer E Ho2,3,4.
Abstract
Background Experimental studies support a link between obesity and pulmonary hypertension (PH), yet clinical studies have been limited. This study sought to determine the association of obesity and pulmonary hemodynamic measures and mortality in PH. Methods and Results We examined patients undergoing right-sided heart catherization (2005-2016) in a hospital-based cohort. Multivariable regression models tested associations of body mass index and pulmonary vascular hemodynamics, with PH defined as mean pulmonary artery pressure >20 mm Hg, and further subclassified into precapillary, postcapillary, and mixed PH. Multivariable Cox models were used to examine the effect of PH and obesity on mortality. Among 8940 patients (mean age, 62 years; 40% women), 52% of nonobese and 69% of obese individuals had evidence of PH. Higher body mass index was independently associated with greater odds of overall PH (odds ratio, 1.34; 95% CI, 1.29-1.40; P<0.001 per 5-unit increase in body mass index) as well as each PH subtype (P<0.001 for all). Patients with PH had greater risk of mortality compared with individuals without PH regardless of subgroup (P<0.001 for all). We found that obesity was associated with 23% lower hazard of mortality among patients with PH (hazard ratio, 0.77; 95% CI, 0.69-0.85; P<0.001). The effect of obesity was greatest among those with precapillary PH (hazard ratio, 0.57; 95% CI, 0.46-0.70; P<0.001), where obesity modified the effect of PH on mortality (P for interaction=0.02). Conclusions Obesity is independently associated with PH. PH is associated with greater mortality; this is modified by obesity such that obese patients with precapillary PH have lower mortality compared with nonobese counterparts. Further studies are needed to elucidate mechanisms underlying obesity-related PH.Entities:
Keywords: obesity paradox; pulmonary hypertension; right‐sided heart catheterization; survival analysis
Mesh:
Year: 2020 PMID: 32079475 PMCID: PMC7335575 DOI: 10.1161/JAHA.119.014195
Source DB: PubMed Journal: J Am Heart Assoc ISSN: 2047-9980 Impact factor: 5.501
Clinical Characteristics by Obesity Class
| Clinical Characteristics | Normal Weight (n=2506) | Overweight (n=3006) | Obesity Class | Total (n=8940) |
| ||
|---|---|---|---|---|---|---|---|
| Class 1 (n=1862) | Class 2 (n=907) | Class 3 (n=659) | |||||
| Age, y | 61±15 | 63±12 | 63±11 | 62±12 | 60±11 | 62±13 | 0.56 |
| Men, % | 51 | 68 | 64 | 60 | 47 | 60 | <0.0001 |
| Race, % | <0.0001* | ||||||
| White | 82 | 85 | 87 | 84 | 86 | 85 | |
| Black | 4 | 4 | 4 | 5 | 6 | 4 | |
| Other | 14 | 11 | 9 | 11 | 8 | 11 | |
| Systolic blood pressure, mm Hg | 124±26 | 124±24 | 128±24 | 130±24 | 129±24 | 126±24 | 0.51 |
| Heart rate, bpm | 74±16 | 71±15 | 71±15 | 73±16 | 74±15 | 72±16 | 0.95 |
| Body mass index, kg/m2 | 22±2 | 27±1 | 32±1 | 37±1 | 45±5 | 29±7 | <0.0001 |
| Current smoker, % | 10 | 8 | 11 | 9 | 10 | 10 | 0.19 |
| Hypertension, % | 45 | 59 | 66 | 70 | 66 | 58 | <0.0001 |
| Diabetes mellitus, % | 13 | 21 | 29 | 35 | 38 | 23 | <0.0001 |
| Obstructive sleep apnea, % | 4 | 8 | 17 | 30 | 43 | 14 | <0.0001 |
| Chronic kidney disease, % | 2 | 3 | 3 | 2 | 3 | 3 | 0.11 |
| Previous myocardial infarction, % | 15 | 20 | 21 | 20 | 14 | 18 | <0.0001 |
| Previous heart failure, % | 30 | 30 | 33 | 34 | 35 | 32 | 0.003 |
| Pulmonary vasodilator medication, % | 1.0 | 0.7 | 0.9 | 0.8 | 0.9 | 0.9 | 0.27 |
| Hemodynamics | |||||||
| Mean PA pressure, mm Hg | 24±11 | 24±10 | 26±11 | 29±11 | 30±11 | 25±11 | <0.0001 |
| Pulmonary capillary wedge pressure, mm Hg | 13±7 | 14±8 | 16±8 | 18±8 | 19±8 | 15±8 | <0.0001 |
| Transpulmonary gradient, mm Hg | 10±8 | 10±7 | 11±7 | 11±8 | 12±8 | 10±8 | <0.0001 |
| Pulmonary hypertension subgroup, % | <0.0001 | ||||||
| Mixed | 11 | 13 | 17 | 21 | 25 | 15 | |
| Precapillary | 15 | 13 | 14 | 13 | 14 | 14 | |
| Postcapillary | 21 | 23 | 26 | 32 | 33 | 25 | |
Data are presented in mean±SD for continues variables or percentage for categorical variables. P values for continuous variables are for ANOVA analyses, and categorical variable P values are from χ2 analyses. Bpm indicates beats per minute; PA, pulmonary artery.
Fisher's exact test because of low numbers in certain race categories.
Figure 1Prevalence of precapillary, postcapillary, and mixed pulmonary hypertension (PH), stratified by obesity class.
Association of BMI With Pulmonary Vascular Hemodynamics and PH Hemodynamic Subtype
| Continuous Traits | Age‐ and Sex‐Adjusted Model | Multivariable‐Adjusted Model | ||
|---|---|---|---|---|
| β (SE) |
| β (SE) |
| |
| mPAP | 1.55 (0.08) | <0.001 | 1.49 (0.08) | <0.001 |
| TPG | 0.037 (0.005) | <0.001 | 0.036 (0.005) | <0.001 |
Multivariable model adjusted for age, sex, heart rate, hypertension, diabetes mellitus, obstructive sleep apnea, chronic kidney disease, previous myocardial infarction, and heart failure. β estimates represent change per 5‐unit increase in BMI. TPG is in log units. BMI indicates body mass index; mPAP, mean pulmonary artery pressure; OR, odds ratio; PH, pulmonary hypertension; TPG, transpulmonary gradient.
Association of Pulmonary Hemodynamics and Obesity with All‐Cause Mortality
| Variable | Age‐ and Sex‐Adjusted Model | Multivariable‐Adjusted Model |
| ||
|---|---|---|---|---|---|
| HR (95% CI) |
| HR (95% CI) |
| ||
| Continuous traits | |||||
| Mean PAP | 1.70 (1.62–1.79) | <0.001 | 1.41 (1.36–1.47) | <0.001 | |
| TPG | 1.48 (1.41–1.55) | <0.001 | 1.37 (1.31–1.44) | <0.001 | |
| Body mass index | 0.96 (0.92–1.00) | 0.05 | 0.91 (0.87–0.96) | <0.001 | |
| Dichotomous traits | |||||
| Obesity | 0.93 (0.86–1.01) | 0.10 | 0.86 (0.78–0.93) | <0.001 | |
| PH | 2.44 (2.22–2.67) | <0.0001 | 2.01 (1.82–2.22) | <0.001 | |
| Precapillary PH | 2.79 (2.47–3.16) | <0.001 | 2.48 (2.19–2.81) | <0.001 | |
| Postcapillary PH | 2.27 (2.03–2.53) | <0.001 | 1.88 (1.68–2.10) | <0.001 | |
| Mixed PH | 3.19 (2.84–3.58) | <0.001 | 2.41 (2.13–2.72) | <0.001 | |
| Effect of obesity among PH subgroups (stratified analyses) | |||||
| Obesity (no PH) | 0.87 (0.73–1.05) | 0.16 | 0.82 (0.67–0.99) | 0.04 | |
| Obesity (PH) | 0.79 (0.72–0.86) | <0.001 | 0.77 (0.69–0.85) | <0.001 | 0.67 |
| Obesity (precapillary PH) | 0.60 (0.49–0.74) | <0.001 | 0.57 (0.46–0.70) | <0.001 | 0.02 |
| Obesity (postcapillary PH) | 0.80 (0.69–0.93) | 0.003 | 0.81 (0.69–0.95) | 0.009 | 0.98 |
| Obesity (mixed PH) | 0.91 (0.77–1.07) | 0.25 | 0.87 (0.73–1.04) | 0.13 | 0.27 |
Multivariable model adjusted for age, sex, heart rate, hypertension, diabetes mellitus, obstructive sleep apnea, chronic kidney disease, previous myocardial infarction, and heart failure. Hazard ratio is expressed per 1‐SD change in continuous predictors and for presence vs absence of dichotomous traits. Transpulmonary gradient is in log units. Interaction is obese×each PH subclass (precapillary/postcapillary/mixed PH) or obese×PH. HR indicates hazard ratio; PAP, pulmonary artery pressure; PH, pulmonary hypertension; TPG, transpulmonary gradient.
Figure 2Survival among obese and nonobese individuals with pulmonary hypertension (PH) subtypes. A, Individuals with and without precapillary PH. B, Individuals with and without postcapillary PH; C, Individuals with and without mixed PH. In the precapillary and postcapillary PH groups, nonobese individuals had decreased survival compared with obese individuals.