title: Incidence of pulmonary hypertension in patients with systemic sclerosis and no pulmonary symptoms: is annual echocardiographic screening necessary?
abstract: BACKGROUND
  Annual echocardiographic screening has been recommended for early detection of pulmonary hypertension (PHT) in systemic sclerosis (SSc) patient; however, the cost benefit for cases with no pulmonary symptoms is not well established.
  
  
  OBJECTIVE
  The objective of this study was to determine the incidence and clinical predictors of echocardiographic diagnosis of PHT in "asymptomatic" SSc patients.
  
  
  METHODS
  A historical cohort of adult SSc patients who underwent echocardiographic screening for PHT at least twice in Khon Kaen University, Thailand, during January 1, 2005, to December 31, 2011, was included. Pulmonary hypertension was defined by an estimate of right ventricular systolic pressure of greater than 40 mm Hg.
  
  
  RESULTS
  A total of 143 medical records were reviewed (female-to-male ratio = 1.7:1). The majority had the diffuse subset (94 cases; 69.6%). Seventy-five (52.4%) were without pulmonary symptoms throughout the follow-up period. Of the 403.1 person-years under observation in the asymptomatic group, only 1 had pulmonary arterial hypertension confirmed by right-sided heart catheterization. The incidence of PHT among such SSc patients was 0.2 per 100 person-years (95% confidence interval [CI], 0.006-0.01 per 100 person-years). The disease duration at the time of PHT detection by echocardiography was 5.1 years. The declining functional class (FC) led to the higher incidence of PHT, with incidence of PHT in those who had declining FC I to FC II and FC I to FC III of 2.1 (95% CI, 0.4-6.0) and 4.2 (95% CI, 0.1-23.3), respectively.
  
  
  CONCLUSIONS
  The incidence of echocardiography-diagnosed PHT among Thai with SSc, and no pulmonary symptoms was low. Annual echocardiography is less beneficial among such patients; repeated echocardiography should instead be performed on those with a declining FC.
authors.affiliation: From the Divisions of *Allergy-Immunology-Rheumatology and †Cardiology, Department of Medicine, Khon Kaen University, Khon Kaen, Thailand.
authors.forename: Chingching
authors.initials: C
authors.lastname: Foocharoen
authors.forename: Ajanee
authors.initials: A
authors.lastname: Mahakkanukrauh
authors.forename: Burabha
authors.initials: B
authors.lastname: Pussadhamma
authors.forename: Sittichai
authors.initials: S
authors.lastname: Netwijitpan
authors.forename: Siraphop
authors.initials: S
authors.lastname: Suwannaroj
authors.forename: Ratanavadee
authors.initials: R
authors.lastname: Nanagara
mesh_terms: D000328:Adult; D015331:Cohort Studies; D015897:Comorbidity; D016001:Confidence Intervals; D015150:Echocardiography, Doppler / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000000981:diagnostic imaging* / Q000453:epidemiology* / Q000503:physiopathology; D015994:Incidence; D008297:Male; D008403:Mass Screening / Q000379:methods / Q000706:statistics & numerical data; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D012595:Scleroderma, Systemic / Q000175:diagnosis* / Q000453:epidemiology* / Q000628:therapy; D012720:Severity of Illness Index; D013785:Thailand / Q000453:epidemiology; D019564:Unnecessary Procedures