麻豆传媒

WASHINGTON, July 13 -- The lifespan for patients with scleroderma has increased significantly since the 1970s, in large measure because of a decline in deaths from renal disease.

A review of data on more than 2,000 patients with scleroderma treated from 1972 through 2001 showed that 10-year survival improved from 54% to 66%, reported Virginia Steen, M.D., of Georgetown University, and Thomas Medsger, M.D., of the University of Pittsburgh.

The investigators found that survival of scleroderma patients improved in each five-year increment studied, and that deaths from renal crisis significantly decreased from 42% in 1972 to just 6% in 2001, they reported in the July issue of Annals of the Rheumatic Diseases.

However, deaths from pulmonary fibrosis increased from 6% to 33%, and there were concomitant increases in deaths from pulmonary hypertension.

The investigators looked at data on 2,105 patients in a scleroderma patient registry developed by Dr. Steen when she was a fellow at the University of Pittsburgh in the early 1980s.

They determined whether the death of each patient was related to scleroderma, and, if so, into which of six categories it should be classified:

• Scleroderma renal crisis, including deaths related to dialysis or renal transplantation,
• Pulmonary arterial hypertension,
• Pulmonary fibrosis,
• Gastrointestinal, including severe involvement of the esophagus or small bowel, resulting in malabsorption, malnutrition or hyperalimentation,
• Cardiac, including primary cardiomyopathy and arrhythmias or conduction defects not attributable to other cardiac conditions and requiring treatment,
• Multi-system organ failure.

Drs. Steen and Medsger saw that there was a steady improvement in 10-year survival for each of the time intervals, and significant improvement in survival for patients from 1982 through 1991 compared with the 1972 through 1981 period (P<0.001). Improvement was significant even when patients with renal crisis were excluded from the analysis (P<0.005).

They also found that the frequency of deaths from renal crisis decreased from 42% to 6% of all scleroderma-related deaths (P<0.001). They attributed the drop largely to earlier diagnosis and aggressive use of ACE inhibitors.

In contrast, the proportion of patients who died from pulmonary fibrosis climbed from 6% to 33% (P<0.001) over the study period. The frequency of pulmonary hypertension independent of fibrosis also increased significantly (P<0.05).

"In all, 60% of scleroderma-related deaths are now from both of these lung complications combined, clearly establishing this as the most important scleroderma problem," the authors wrote.

The frequency of deaths from scleroderma-related gastrointestinal and heart disease and multi-organ failure did not change significantly over the study period.

Half of all patients with scleroderma now die of non-scleroderma-related causes, the authors noted, compared with 30% in the 1970s.

"This is really good progress, which we hope to improve upon," said Dr. Steen.

The authors noted that several new therapies for pulmonary arterial hypertension have been introduced, and that there is evidence from short-term studies suggesting that they improve survival in patients with scleroderma-related PAH, although longer study is needed.

"The change in the distribution of scleroderma-related deaths over the past 30 years confirms that lung disease (both pulmonary hypertension and pulmonary fibrosis) is the primary cause of scleroderma-related deaths today," they wrote. "It is important that aggressive searches continue to develop better therapies for these severe pulmonary complications of systemic sclerosis."

The study was supported by the Scleroderma Foundation. The authors reported that they had no conflicts of interest.

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