Homocysteine,s correlation with Impaired Diffusion Capacity of the Lung for Carbon Monoxide: A predictive biomarker
Research has suggested that Hyperhomocysteinemia increased the risk of thrombus formation, by irritating the lining of the blood vessels. Although it is considered as a cardiovascular predictor but none of the studies have examined its role as a pulmonary biomarker. The purpose of the study was to describe the association of homocysteine with pulmonary diffusion capacity.
The study subjects included four hundred patients examined by a pulmonologist at an outpatient clinic in Texas. For each patient, socio-demographic, laboratory and clinical information about co-morbid conditions (OSA, hypertension and diabetes, cardiac diseases) and measurement of the diffusing capacity for carbon monoxide (DLCo) were obtained. Logistic models with forward selection methods were employed and the outcome variable was impaired diffusing capacity of the lung for carbon monoxide (DLCo less than 69%) and predictor variable homocysteine >12 μmol/L.
Hundred sixty patients (41%) with low diffusion capacity of lung for carbon monoxide were mostly older (74% were above age 65), females, nonsmoker, and obese (62%). Out of those 41%, 14.2% have mild, 10.5 moderate and 17.7% severely impaired lung diffusion.
Unadjusted logistic regression show that high Homocystein levels are 2.5 time more likely to be associated with impaired lung diffusion capacity (OR 2.54, P=0.01). Multivariate analysis after controlling for age, gender and ethnicity and comorbid conditions indicated that high Homocystein was significantly associated with lung diffusion capacity impairment after (OR 2.50, P=0.03).
In asthmatic the association of Homocystein with lung diffusion was statistically significant (OR 2.30, P=0.02), while in nonasthmatic the Homocystein and DLCo correlation was not statistically significant. (OR 1.21, P=0.71)
Hyperhomocysteinemia is associated with impairment of lung diffusion in adult patients and specifically those who were asthmatic.
Risk-identification in specific patient population will improve the quality of customized patient care and dissemination of relevant information about co-morbid condition as an additional cardio-pulmonary risk to the patients and healthcare providers will result in early prevention and improved patient’s outcomes.