Table 1.

Prevalence of idiopathic pulmonary arterial hypertension and prevalence of PAH in patients with connective tissue diseases

Author, title, journal	Published year	Study period	Objectives	Data source	Disease definition	Country	Prevalence (patients with PAH/sample size)
Idiopathic pulmonary arterial hypertension
Peacock A.J., et al. An epidemiological study of pulmonary arterial hypertension. Eur Respir J	July 2007	National hospitalization registry data: between 1986 to 2002	To determine the epidemiological features of PAH within a whole population over a prolonged period from two perspectives, inexpert and expert, a national hospitalization registry and the specialist center for PAH management in Scotland.	National hospitalization registry data in Scotland	Having code of PAH in the absence of any explanatory concurrent diagnosis from prior hospitalizations based on combination of concurrently recorded diagnoses and coding data from any prior hospitalizations	Scotland	25 cases per million population (80/3, 200,000)
Humbert M, et al. Pulmonary arterial hypertension in France: results from a national registry. Am J Respir Crit Care Med	May, 2006	Between October 2002 to October 2003	To describe clinical and hemodynamic parameters and to provide estimates for the prevalence of PAH patients diagnosed for PAH according to a standardized definition	National registry in 17 university hospitals in France	Mean pulmonary arterial pressure >25 mm Hg at rest and a pulmonary artery wedge pressure less than 15 mm Hg	France	5.9 cases per million population (264/44, 700,000)
Tueller C, et al. Epidemiology of pulmonary hypertension: new data from the Swiss registry. Swiss Med Wkly	June, 2008	Between January 1999 to December 2004	To analyze the epidemiological aspects of data from all pulmonary hypertension (PH) centers in Switzerland and focus on basic clinical characteristics of PH patients and estimated burden of the disease in the population	PH patient registry from all PH centers in Switzerland	Not specified (PH was defined as a mean pulmonary artery pressure of >25 mm Hg at rest or >30 mm Hg during exercise) 72 % of patients underwent right heart catheterization	Switzerland	8.6 cases per million population (52/6,000,000)
PAH in systemic sclerosis
Hachulla E, et al. Early detection of pulmonary arterial hypertension in systemic sclerosis: a French nationwide prospective multicenter study. Arthritis Rheum	2005	Between September 2002 to July 2003	To develop an screening algorithm based on symptoms, echocardiography, and right heart catheterization for application to a nationwide multicenter systemic sclerosis population in France	Data from 21 systemic sclerosis centers in France	A mean pulmonary artery pressure ≥25 mm Hg at rest or ≥30 mm Hg during exercise, with pulmonary artery wedge pressure <15 mm Hg on right heart catheterization	France	7.85 % (47/599)
Hachulla et al. Risk factors for death and the 3-year survival of patients with systemic sclerosis: the French ItinerAIR-Sclerodermie study. Rheumatology	2009	Between September 2002 and July 2003	To investigate survival, risk factors and causes of death in the multicenter ItinerAIR-Sclerodermie cohort of patients with systemic sclerosis without severe pulmonary fibrosis or severe left heart disease at baseline	Data from 20 French specialized scleroderma centers	A mean pulmonary arterial pressure ≥25 mm Hg at rest or ≥30 mm Hg during exercise, with mean pulmonary arterial wedge pressure <15 mm Hg on right heart catheterization	France	8.6 % (47/546)
Avouac, et al. Prevalence of pulmonary hypertension in systemic sclerosis in European Caucasians and metaanalysis of 5 studies. J Rheumatol	2010	Not specified. (Point prevalence estimation)	To measure the prevalence of the different types of PH, using right heart catheterization, in 2 large European samples of patients presenting with systemic sclerosis.	Data from patients with systemic sclerosis at 6 French and 5 Italian medical centers	A mean resting pulmonary artery pressure of >25 mm Hg in the presence of a pulmonary capillary wedge pressure of ≤15 mm Hg at right heart catheterization, in the absence of prominent interstitial lung disease	France and Italy	3.6 % (42/1,165)
Vonk et al. Systemic sclerosis and its pulmonary complications in The Netherland: an epidemiological study. Ann Rheum Dis	2009	Between 2005 and 2006	To establish the prevalence and incidence of systemic sclerosis and its pulmonary complications	Combination of “Pulmonary Hypertension Screening, a Multidisciplinary Approach in Scleroderma” registry and a nationwide questionnaire	A mean pulmonary arterial pressure >25 mm Hg at rest with a normal wedge pressure on right heart catheterization	The Netherlands	9.9 % (113/1,148)
Phung et al. Prevalence of pulmonary arterial hypertension in an Australian scleroderma population: screening allows for earlier diagnosis. Intern Med J	2009	Between July 1, 2005 and June 30, 2007	To determine the prevalence of pulmonary complications, and especially PAH in an Australian scleroderma population	Data from Royal Perth Hospital (the state referral center for adult pulmonary hypertension)	A mean pulmonary artery pressure ≥25 mm Hg at rest or ≥30 mm Hg during exercise, with a concomitant pulmonary capillary wedge pressure <15 mm hg and pulmonary vascular resistance of >240 dynes/s per cm−5 on right heart catheterization	Australia	13 % (24/184)
de Azevedo et al. Prevalence of pulmonary hypertension in systemic sclerosis. Clin Exp Rheumatol	2005	November 2001 to March 2003 (a cross sectional study)	To determine the prevalence of PAH in patients with a diagnosis of systemic sclerosis followed in a Brazilian tertiary university service	Data from patients with systemic sclerosis followed at the Unit of rheumatology of a university hospital	Pulmonary artery systolic pressure ≥40 mm Hg estimated by ECHO with the estimated right atrial pressure being 14 mm Hg, and/or as the presence of direct or indirect signs of PAH	Brazil	14 % (8/57)
Coral-Alvarado et al. Risk factors associated with pumonary arterial hypertension in Colombian patients with systemic sclerosis: Review of the literature. J Rheumatol	2008	Not specified (a cross sectional study)	To investigate the clinical and laboratory characteristics associated with PAH in Colombian patients with systemic sclerosis	Data of patients with systemic sclerosis in five rheumatology units	A mean pulmonary artery systolic pressure >25 mm Hg at rest or a tricuspid regurgitation velocity >3 m/s or 2.5 m/s with unexplained dyspnea by echocardiogram	Colombia	17 % (61/349)
Kumar et al. Prevalence and predictors of pulmonary artery hypertension in systemic sclerosis. J Assoc Physicians India	2008	Between 2004 to 2007 (a cross sectional study)	To study the prevalence of PAH in systemic sclerosis; to study the predictors of PAH in systemic sclerosis	Data from patients with systemic sclerosis at All India Institute of Medical Sciences	Transtricuspid gradient >35 mm Hg or right ventricular acceleration time of <90 ms.	India	32 % (32/100)
Pope et al. Prevalence of elevated pulmonary arterial pressures measured by echocardiography in a multicenter study of patients with systemic sclerosis. J Rheumatol	2005	Between June 2002 and May 2003	To estimate the prevalence of elevated pulmonary arterial pressures as a correlate for pulmonary arterial hypertension in patients with systemic sclerosis in rheumatology centers in Canada	Data from systemic sclerosis patients receiving care at rheumatology centers in Canada	systolic pulmonary arterial pressure >30 mm Hg or >35 mm Hg	Canada	23 % (124/539)
Gińdzieńska-Sieśkiewicz et al. The occurrence of pulmonary hypertension in patients with systemic sclerosis hospitalized in the department of rheumatology and internal diseases medical university of Bialystok in years 2003–2004	2005	Between 2003 and 2004	To investigate the occurrence of pulmonary hypertension in systemic sclerosis patients hospitalized in Department of Rheumatology and Internal Diseases University Hospital of Bialystok	Data from patients with systemic sclerosis hospitalized in Department of Rheumatology and Internal Diseases University Hospital of Bialystok	A pulmonary artery systolic pressure >35 mm Hg by Doppler echocardiography	Poland	6 % (3/53)
Chang et al. Scleroderma patients with combined pulmonary hypertension and interstitial lung disease. J Rheumatol	2003	Between January 1, 1990 and August 31, 2001(a cross-sectional study)	To study the demographics, clinical features, and prognosis of individuals with both vascular and interstitial lung disease	Data from patients with scleroderma seen at least once at a Scleroderma Center	Right ventricular systolic pressure or pulmonary artery pressure >35 by echocardiography	United States	19.2 % (119/619)
Yamane et al. Clinical and laboratory features of scleroderma patients with pulmonary hypertension. Rheumatology (Oxford).	2000	Between 1990 and 1999 (a cross sectional study)	To examine the occurrence of pulmonary hypertension and investigated the clinical and laboratory features of systemic sclerosis patients with pulmonary hypertension	Data from 125 Japanese patients with systemic sclerosis	Pulmonary artery systolic pressure >40 mm Hg in absence severe pulmonary fibrosis	Japan	11.2 % (14/125)
PAH in lupus
Pan et al. Primary and secondary pulmonary hypertension in systemic lupus erythematosus. Lupus	2000	1995	To describe the etiology and clinical profile of primary and secondary pulmonary hypertension in systemic lupus erythematosus patients	Data from 786 systemic lupus erythematosus patients diagnosed with SLE over the last twenty years at Tan Tock Seng Hospital	A pulmonary artery systolic pressure >30 mm Hg measured by Doppler analysis of tricuspid valve regurgitant jet velocity or right heart catheter measurements at angiography	Singapore	2.8 % (22/786)
Prabu et al. Prevalence and risk factors for pulmonary arterial hypertension in patients with lupus. Rheumatology (Oxford)	2009	Between January 2004 to December 2005 (a cross-sectional study)	To estimate the point prevalence of PAH and identify risk factors for PAH in a large cohort of systemic lupus erythematosus patients	Data from lupus clinics in Birmingham, UK	Systolic pulmonary artery pressure >30 mm Hg by echocardiography	UK	4.2 % (12/283)
PAH in rheumatoid arthritis
Dawson et al. Raised pulmonary artery pressures measured with Doppler echocardiography in rheumatoid arthritis patients. Rheumatology	2000	Not specified (a cross-sectional study)	To study the prevalence of echocardiographic abnormality and pulmonary hypertension in an unselected population of patients with rheumatoid arthritis	Data from 146 patients with rheumatoid arthritis in rheumatology outpatient departments of St Helens and Knowsley Hospitals NHS Trust	Estimated pulmonary arterial systolic pressure ≥30 mm Hg	UK	21 % (30/146)
Keser et al. Pulmonary hypertension in rheumatoid arthritis. Scand J Rheumatol	2004	April 2002 and October 2002	To investigate pulmonary arterial systolic pressure in rheumatoid arthritis using Doppler echocardiography	Data from 40 consecutive rheumatoid arthritis patients attending the Ege University Rheumatology Department	An estimated pulmonary arterial systolic pressure >30 mm Hg	Turkey	27.5 % (11/40)
PAH in combined patients with systemic sclerosis and mixed connective tissue diseases
Wigley et al. The prevalence of undiagnosed pulmonary arterial hypertension in subjects with connective tissue disease at the secondary health care level of community-based rheumatologists (the UNCOVER study). Arthritis Rheum	2005	Not specified (point prevalence estimation)	To determine the point prevalence of undiagnosed PAH in community-based rheumatology practice by conducting a survey using Doppler echocardiography technology	Data from patients with connective tissue diseases in fifty community-based centers	According to current rheumatologist at the time of chart review; or estimated right ventricular systolic pressure ≥40 mm Hg	United States and Canada	26.7 % (211/791)