Kathryn Stackhouse

Impact of diabetes in patients with pulmonary hypertension

Diabetes complicates management in a number of disease states and adversely impacts survival; how diabetes affects patients with pulmonary hypertension (PH) has not been well characterized. With insulin resistance having recently been demonstrated in PH, we sought to examine the impact of diabetes in these patients. Demographic characteristics, echo data, and invasive hemodynamic data were prospectively collected for 261 patients with PH referred for initial hemodynamic assessment. Diabetes was defined as documented insulin resistance or treatment with antidiabetic medications. Fifty-five patients (21%) had diabetes, and compared with nondiabetic patients, they were older (mean years ± SD, 61 ± 13 vs. 56 ± 16; P = 0.02), more likely to be black (29% vs. 14%; P = 0.02) and hypertensive (71% vs. 30%; P < 0.001), and had higher mean (±SD) serum creatinine levels (1.1 ± 0.5 vs. 1.0 ± 0.4; P = 0.03). Diabetic patients had similar World Health Organization functional class at presentation but were more likely to have pulmonary venous etiology of PH (24% vs. 10%; P = 0.01). Echo findings, including biventricular function, tricuspid regurgitation, and pressure estimates were similar. Invasive pulmonary pressures and cardiac output were similar, but right atrial pressure was appreciably higher (14 ± 8 mmHg vs. 10 ± 5 mmHg; P < 0.001). Despite similar management, survival was markedly worse and remained so after statistical adjustment. In summary, diabetic patients referred for assessment of PH were more likely to have pulmonary venous disease than nondiabetic patients with PH, with hemodynamics suggesting greater right-sided diastolic dysfunction. The markedly worse survival in these patients merits further study.

OUTCOME OF LUNG DISEASE-RELATED PULMONARY HYPERTENSION AND IMPACT OF PULMONARY VASOREACTIVITY

methods: From a two-center prospective cohort of PH patients referred for initial hemodynamics, we identified 70 patients with LD-PH. Causes included obstructive lung disease in 22, interstitial lung disease in 18 and sarcoidosis in 23. Baseline characteristics and long-term survival were compared with 88 patients with idiopathic PH (iPH). Vasoreactivity was defined by 30% drop in mean pulmonary artery pressure (mPAP) during inhalation of 40 ppm nitric oxide.

DOES PATIENT SELECTION MAKE THE CLOSURE STUDY LESS APPLICABLE

Results: Between 11/5/03 and 4/16/07 there were 100 off-label closures and 33 patients randomized into CLOSURE I. Compared with off-label closure, patients in CLOSURE I were younger (41.6+10.1 vs. 50.0+14.0, p=0.0005) and had fewer cardiovascular risks including hypertension (6% vs. 36%, p=0.0007), hyperlipidemia (24% vs. 52%, p=0.008) and prevalent coronary disease (3% vs. 44%, p<0.0001). Baseline hemoglobin was lower in off-label closures (14.5+/-1.3 vs. 13.7+/-1.7, p=0.018). Though most echocardiographic comparisons were underpowered, degree of rightto-left shunt was considerably higher in off-label closures (28/14/58% vs. 45/30/25%, mild/moderate/severe, p=0.026). The degree of shunting in our CLOSURE patients was similar to that previously reported for the entire study.