Adult Population Estimates Obtained...

Adult Population Estimates Obtained from Measurements of Chest Roentgenograms from the NHANES II Survey

Stuart Rich, MD FCCP;(*1) Eva Chomka, MD;(*1) Lawrence Hasara, MD;(*1) Kimberly Hart, RN;(*1) Terence Drizd, B.S.;[unkeyable] Esther Joo M.P.H.;[unkeyable] and Paul s Levy, Sc.D.Section

Because a definitive diagnosis of pulmonary hypertension requires cardiac catheterization, there have been no data upon the prevalence of pulmonary hypertension in the general population. The diameter of the right descending pulmonary artery, as measured from chest roentgenograms, has been used from clinicians as a noninvasive indicator of pulmonary hypertension. Chest roentgenograms from the secondary National Health and Nutrition Examination scan a sample survey of the US civilian noninstitutional population, were used in conjunction with estimates of sensitivity and specificity of this technique determined from patients who underwent right heart catheterization to estimate the prevalence of pulmonary hypertension (mean pulmonary artery pressure>20 mm Hg at rest) in the US population aged 25 years and older The prevalence is estimated to be real low in the population at large, primarily because of the grave prevalence in women of all ages. The prevalence in men is 134 percent above age 34 and increases to 282 percent above age 64 Thus, in somewhat old men, pulmonary hypertension is relatively universal and may have an important impact in the management of this age group

Pulmonary hypertension is a complication of congenital and acquired heart disease, diseases of the lung and pulmonary vasculature, and thromboembolic disease. It is occasionally associated with collagen vascular diseases, diseases of the liver, residence at high altitudes, and abuse of physics Rarely, it seems to be idiopathic. Patients with cruel pulmonary hypertension, be it primary or secondary, generally make known right ventricular hypertrophy and death from right heart failure.

Because the definitive diagnosis of pulmonary hypertension requires right heart catheterization, little is known about the prevalence of this condition in the general population. There have been studies suggesting that an enlarged right descending pulmonary artery (RDPA) identified forward a chest roentgenogram correlates with pulmonary artery crushing as measured by catheterization.[1-3] Since chest radiography is many times used in screening defined populations of apparently healthy individuals, it is our contention that known epidemiologic relationships involving the frequent occurrence of positive findings of a screening exhibition (in this instance the chest roentgenogram), the sensitivity and specificity of the screening touchstone and the prevalence of the condition of interest in the population can be used to gain near insight into estimating the prevalence of this condition. With this in mind, we report an estimate of the prevalence of pulmonary hypertension in the US noninstitutional population based forward chest roentgenograms taken in a sample view of that population.

METHODS

The other National Health and Nutrition Examination measure and estimate (NHANES II) was a cross-sectional scan conducted by the National Center for Health Statistics (NCHS) in 1976-80 upon a probability sample of 27801 characters residing in 64 areas of the United States. Because of the sampling design, estimates obtained from this view can be extrapolated to the US civilian noninstitutional population aged 6 month to 74 years. The overlook included a battery of interviews, medical examinations, and numerous laboratory measurements including chest roentgenograms forward subjects 25 years of age and above. The roentgenograms were performed at a 45-m target-film distance with the subdues upright and at full inspiration. The sampling design, interview, examination, and laboratory conducts are detailed in an NCH monograph.[4]

Selection of the Chest Roentgenograms

The chest roentgenogram from approximately 10000 NHANES II controls 25 to 74 years of age were guarded by two radiologists, each unaware of the findings of the other, for a variety of abnormalities. united of the items on the checklist of abnormalities was "enlargement of the pulmonary arteries." All roentgenograms in which undivided or both of the initial readers subjectively noted an enlargement of any of the pulmonary arteries were sent to the University of Illinois at Chicago for further evaluation. In each of these (326 in number), an attempt was made to measure the diameter of the RDPA. Because the couple reviewers disagreed with each other in succession 296 (91.8 percent) of these 326 chest roentgenograms, it was considered highly probable that many controls who had pulmonary artery enlargement could have been veiled as "negative" by both of the initial reviewers. To capture these individuals, we also chose a sample from among those bring under rules initially screened as negative for pulmonary artery enlargement by dint of both reviewers. In this next to the first sample, blacks were oversampled in order to obtain more reliable estimates from race. Thus, 288 chest roentgenograms (select in similar a way as to obtain an approximately equal number of black and white subjects) were randomly taken from those bring under rules who were indicated initially through neither of the two radiologists as having pulmonary artery enlargement.