About 64% of rheumatoid patients had restrictive ventilatory defect and 10% of rheumatoid patients had obstructive type.
Restrictive ventilatory defect is seen in 64% of rheumatoid patients with FEV1/FVC >70% and reduced vital capacity and total lung capacity.
Among 3 cases moderate severe obstruction in 1(33.33%), moderate restriction in 1(33.33%), mixed obstructive and restrictive ventilatory defect in 1(33.33%) were preent.
Pleural lesions cause compression of the lung and hence reduces its volumes leading to a restrictive ventilatory defect. The causes of pleural lesions are many fold.
Pulmonary function tests may be normal in mild cases but generally there is restrictive ventilatory defect
with reduced diffusing capacity of the lung for carbon monoxide (DLCO).
TLD is defined as the presence of respiratory symptoms and/or diffuse infiltrates on chest radiographs, abnormal pulmonary function tests with evidence of restrictive ventilatory defect
and/or impaired gas exchange and persistence of any of these findings for greater than 3 months'2.
The results of pulmonary function tests showed decreased diffusion capacity (n=4), restrictive ventilatory defect (n=3), moderate obstructive ventilatory defect (n=1) and were completely normal in 1 patient.
Clinical characteristics of the cases Clinical characteristics Number of cases (n) Cough 4 Dyspnea 4 Sputum 3 Fever 3 Weight loss 3 Hemoptysis 1 Bilateral inspiratory crackles 4 Normal physical examination 1 Decreased diffusion capacity 4 Restrictive ventilatory defect 3 Obstructive ventilatory defect 1 Normal pulmonary function 1 Bilateral infiltrations 4 Focal opacity 1 Transthoracic biopsy 4 Transbronchial biopsy 1 All the patients were classified as cryptogenic, except a 49-year-old woman who presented with normocapnic respiratory failure and acute renal failure.
Classically, a restrictive ventilatory defect (restriction) is defined as a reduced total lung capacity (TLC).
In a following study from the same laboratory, Glady developed an algorithm to predict the presence of a restrictive ventilatory defect in individual patients.
In conclusion, mainly a restrictive ventilatory defect
was associated with GORD in elderly patients.
There were 11(36.6%) patients with restrictive ventilatory defect
without radiological abnormalities, 7(23.3%) patients with diffusion defects without radiological abnormalities.