Pulmonary diffusing capacity for nitric oxide (DLNO) is a relatively new pulmonary function test to assess gas transfer in the lung. To date, there are no prediction equations made for healthy adult African-American (black) subjects. Thus, the purpose of this study was to create prediction equations for DLNO in this ethnic/racial group. A total of 59 healthy subjects (27 males and 32 females) were recruited to perform pulmonary function testing at Georgia State University. They were diverse in age (18-67 yr), height (140-189 cm), and body mass index (17.2-32.3 kg/m2). All subjects completed single-breath maneuvers at rest inhaling 43 ± 4 ppm NO with a standard diffusion mixture. The breath-hold duration was 5.6 ± 0.6 s. Multiple linear regression predicted DLNO based on the subject’s age, height, and sex. The prediction equation for DLNO (mL/min/mmHg) = 0.92·(height in cm) +38.8·(sex) – 0.012·(age2) – 25, where 1 = male, 0 = female for sex. About 77% of the variance in DLNO was accounted for by sex (67%), age2 (7%), and height (4%). The standard error of the estimate in predicting DLNO was 16.3 mL/min/mmHg. Those with higher resting heart rates had a lower DLNO (r =-0.28, p = 0.03) but it was not included in the regression model as it did not enhance the fit. Black males had a 7-10% lower DLNO and black females had a 12-15% lower DLNO compared to matched white subjects. Black males of the same age and height had a 10% smaller alveolar volume, while black females had a 15% lower alveolar volume compared to matched white subjects. In conclusion, DLNO values and alveolar volumes are reduced in blacks compared to matched whites. The regression model presented best predicts DLNO in African-Americans below 40 years of age.

Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 5 uppsatser.

Familial amyloidosis with polyneuropathy (FAP) was first reported from Portugal in 1952, but since then this syndrome has been recognized in many countries including Sweden. In this investigation cardiac and pulmonary functions in the Swedish variety of FAP were studied. A retrospective survey of the ECG findings in 71 patients showed a high prevalence of atrioventricular (38%) and intraventricular (41%) conduction defects, and also a high prevalence of atrial fibrillation (14%). In several patients a progression in the conduction defects to advanced disturbances could be observed and 10 out of 71 patients (14%) in the present series required pacemaker treatment. A histopathological study of the atrioventricular part of the conduction system showed marked amyloid infiltration in each case, which may explain the high prevalence of conduction defects. In an échocardiographie study which emcompassed 22 consecutive patients, all but those two patients with the shortest duration of symptomatic disease showed abnormal features. The most frequent and characteristic findings were hypertrophy of the interventricular septum (86%) and a hyperrefractile appearance of the iryocardium (68%). This unusual association of échocardiographie features is considered almost diagnostic of cardiac amyloidosis. A hemodynamic study showed an essentially normal systolic heart function, but in several patients there were signs of impaired diastolic function with increased myocardial rigidity. Several patients showed signs of obstruction of the ventricular outflow tracts. This finding, as well as the échocardiographie features, is in accordance with altered anatomical and functional properties of the interventricular septum. The major pulmonary function abnormalities were decreased maximum respiratory pressure which indicate that the neuropathy in FAP involves the respiratory musculature, and impaired diffusing capacity consistent with an alveo-capillary block caused by amyloid deposits. / digitalisering@umu