Associated factors of early-onset pulmonary hypertension and clinical difference between early- and late-onset pulmonary hypertension in Thai systemic sclerosis

Abstract

Objectives

Pulmonary hypertension (PH) is a major cause of death in systemic sclerosis (SSc). Detection of early-onset PH and its associated factors would be helpful for improving patient care. Our aims were to determine the factors associated with early-onset PH and to define the differences between early- and late-onset PH among SSc patients.

Methods

A cohort study was conducted of 409 adult SSc patients who had followed-up between January 2014 and December 2016. Early-PH is defined when the onset of PH is diagnosed within 5 years of the disease. Logistic regression analysis was applied to determine the factors associated with early-PH.

Results

In 3409 person-years, we diagnosed 50 cases with PH confirmation by right heart catheterization, of whom 26 were early-PH (incidence 0.7 per 100 person-years; 95%CI:0.5–1.1). Among SSc with early-PH, 69.2% had the diffuse cutaneous SSc subset and the most common PH classification was PH due to interstitial lung disease (18 cases;69.2%). According to a logistic regression analysis, early-PH was associated with a WHO functional class (WHO-FC) II and higher, cardiomegaly according to chest radiography, and tricuspid regurgitation jet maximum velocity (TRVmax)>2.8 m/s with the respective OR of 20.12 (95%CI:1.59–255.35), 7.42 (95%CI:1.35–40.88), and 8.20 (95%CI:1.17–57.64). To contrast, early-PH had a negative association with gastrointestinal involvement (OR 0.08; 95%CI:0.01–0.56).

Conclusions

Early-PH is prevalent among SSc patients and the most common cause is interstitial lung disease. A poor WHO-FC, cardiomegaly, and a high TRVmax are associated with early-PH. Gastrointestinal involvement is a protective factor for early-PH in SSc.

Keywords:

• Systemic sclerosis
• scleroderma
• pulmonary hypertension
• right heart catheterization
• pulmonary arterial hypertension

Acknowledgements

The authors thank (a) the Scleroderma Research Group and the Faculty of Medicine, Khon Kaen University for their support, and (b) Mr. Bryan Roderick Hamman for assistance with the English-language presentation under the aegis of the Publication Clinic Khon Kaen University, Thailand.

Author contributions

TK collected the data and drafted the manuscript. CF conceived of, designed the study and approved the final manuscript. CF, AM, SS, and RN read and commented on the manuscript.

Ethics approval

The Human Research Ethics Committee of Khon Kaen University reviewed and approved the study per the Helsinki Declaration and the Good Clinical Practice Guidelines (HE621106). All eligible patients signed informed consent before entry to the cohort study. All of the authors consent to publication and grant the publisher exclusive license of the full copyright.

Conflict of interest

None.

Availability of data and materials

Data or materials are available on request.

Additional information

Funding

The study received funding support from the Faculty of Medicine, Khon Kaen University, Thailand.