Success For Insurers in Asbestos Litigation

In that case the Claimant claimed damages for personal injury  including past and future loss of earnings allegedly caused by asbestos exposure in the course of his employment by five employers. Between 1967 and 1991 he had worked successively for each of the Defendants as a pipe fitter, who all admitted wrongful exposure to asbestos in agreed proportions. The Claimant had smoked an average of 20 cigarettes a day during the period 1965 to 2000. It was agreed between the medical experts that he had developed asbestos related pleural plaques (PP) but that they had not caused him any disability and probably never would do so. He suffered from respiratory disability of about 20%.

 

The principle issue in the case was whether the Claimant’s respiratory disability was caused or contributed to by actionable (ie diffuse) pleural thickening (PT) resulting from his admitted asbestos exposure. In order to decide the matter the Court was required to consider the “very confusing” medical terminology involved, extensive medical records, lung function tests and various scans as well as medical literature.

 

Although the body has mechanisms for clearing or neutralising inhaled asbestos fibres the proportion of inhaled asbestos will remain in the lung throughout the lifetime of the person exposed. Pleural plaques are the most common effects of asbestos inhalation and have well demarcated edges and usually develop on the parietal pleura. They do not lead to other asbestos related conditions but can indicate exposure to asbestos fibres. Pleural thickening is diffuse and does not have well demarcated edges. If extensive it restricts lung function and causes breathlessness. Diffuse pleural thickening (DPT) results in thickening of the visceral pleura causing the space between the parietal and visceral pleura to be obliterated (the costophrenic angle). 

In recent years those who administer the industrial injury benefit system have looked for such blunting (or obliteration) of the angle as a clear test for the presence of DPT and entitlement to benefits. Until this redefinition, a broader assessment was made and obliteration of the angles was not required to claim benefits. In the Claimant’s case the angles were not affected but he continued to receive benefits, and he sought to rely upon the fact that he was receiving benefits upon a diagnosis of DPT without his costophrenic angle being obliterated. 

 

The Claimant’s expert relied heavily upon lung function tests to indicate that the lungs were small. This symmetrical reduction in lung function tests was caused by pleural thickening because there was no evidence of weak muscles or chest wall deformity. However, given the Claimant’s ability to perform the lung function tests was variable the Court found that greater reliance should be attached to the objective evidence produced by the Defendants in the form of thoracic CT scans which showed no suggestion of DPT or asbestosis but indicated hyper-inflation which was a common feature of COPD from smoking. The Claimant’s medical expert was criticised for changing his view at trial. In the joint statement he had agreed that airflow obstruction had accounted for one half of the Claimant’s respiratory disability, a view he resiled from in his oral evidence when he sought to attribute the whole disability to pleural thickening when there had been no new factor to justify the expert moderating his view.

 

There were other factors that on balance of probabilities provided a more plausible explanation for the Claimant’s respiratory disability. Medical records provided a chronology of the treatment which the Claimant had received for COPD, a smoking related illness, in the form of inhalers. In recent years the prescription for inhalers had increased because there were indications that this treatment had produced successful results. Conversely, such inhalers would have had no effect upon his respiratory disability if it was caused by his asbestos condition. Increase in age was a further factor to take into account.

 

The Court preferred the Defendants’ medical expert evidence and concluded that the Claimant’s disability was unrelated to his asbestos condition as he had pleural plaques. The radiological evidence did not go so far as to indicate extensive pleural thickening. In arriving at this conclusion the Court  acknowledged that a treating consultant on one occasion considered that an x-ray and CT scan suggested bilateral pleural thickening and another consultant had considered the Claimant had significant restrictive lung disease which he related to pleural plaques. Both of these views were discounted because the Court accepted that it had to evaluate the evidence of the medico legal experts rather than the briefly expressed views of those treating the Claimant. It was therefore held that symptomatic pleural plaques are not actionable and the Court followed the case of Rothwell v- Chemical Insulating Co Ltd (2007).

This area of law involves terminology which can be very confusing and care should be taken to avoid placing too much reliance upon a diagnosis by treating experts who may not have had reliable tests or scans to make a diagnosis for medico legal purposes. Effort dependant tests (lung function) can prove to be unreliable and any expert relying upon them as the foundation of an opinion in preference to more reliable objective tests (radiology) should be challenged.

 

The Court will take a dim view of an expert who seeks to resile from the view expressed in a joint statement where there are no new factors to cause that change of opinion. A diagnosis of a condition for the purposes of the statutory scheme for Industrial Injuries Benefits will not necessarily persuade a Court that damages should be awarded in a civil claim where there are different standards of proof required to satisfy the test of medical causation.