The comorbidity burden and disease phenotype in pre-capillary pulmonary hypertension: The contributing role of obstructive sleep apnea.

BACKGROUND

Pre-capillary pulmonary hypertension (PH) with risk factors for left ventricular diastolic dysfunction, described as an atypical phenotype of "mixed" pre- and post-capillary PH, has become a research focus. However, the relationship between obstructive sleep apnea (OSA), a known risk factor for cardiometabolic conditions, and comorbidity burden and disease phenotype in PH remains unclear.

OBJECTIVE

This study aimed to investigate the effect of the presence and severity of OSA on the left ventricular function, comorbidity burden and disease phenotype in pre-capillary PH patients.

METHODS AND

RESULTS

We retrospectively examined 450 consecutive pre-capillary PH patients undergoing cardiorespiratory polygraphy and right heart catheterization between May 2020 to November 2021 at Fuwai Hospital. The prevalence of OSA was 34.2%, and the presence and severity of OSA in pre-capillary PH patients was associated with increased left heart mass index (P < 0.001), pulmonary arterial wedge pressure (P = 0.06) and H2FPEF score (P < 0.001). After adjustment for confounding factors, the severity of OSA measured as apnea-hypopnea index (AHI) was an independent risk factor associated with obesity, systemic hypertension, diabetes mellitus and an atypical phenotype (OR: 1.054, P = 0.004) in pre-capillary PH. A dose-response relationship was also identified between sleep parameters (AHI, oxygen desaturation index, the percentage of sleep time with oxygen saturation<80%) and the number of key comorbidities. Patients with ≥3 comorbidities (atypical phenotype) were older, experienced negative alterations in left ventricular structure and function, and were at a higher risk of OSA.

CONCLUSION

OSA is relatively prevalent in pre-capillary PH patients, independently associated with the presence of a variety of comorbidities and the atypical phenotype of PH. These findings highlight the importance of OSA as a modifiable target for optimal treatment in PH with comorbidities.