NASHVILLE, TENN. – By 2010, U.S. octogenarians with acute ischemic stroke received intravenous thrombolytic treatment about as often as younger patients, showing that a sharp, age-related disparity in thrombolytic use a decade before had disappeared, based on comprehensive national data.

The 2010 data from the Nationwide Inpatient Sample further showed that the sex-based disparity in treatment with intravenous tissue plasminogen activator (TPA) seen in 2000 resolved as well from 2000 to 2010, but other disparities worsened with declines during the period in use of TPA at rural hospitals relative to urban hospitals and at nonteaching hospitals, compared with teaching hospitals, Dr. Michelle P. Lin said at the International Stroke Conference.

Dr. Michelle P. Lin

Dr. Michelle P. Lin

Perhaps most importantly, the statistics showed a “dramatic” increase in TPA use among all age groups during the decade ending in 2010, when thrombolytic therapy was administered to 3.5%-3.9% of adult patients regardless of their age, said Dr. Lin of the department of neurology at the University of Southern California in Los Angeles. In 2000, U.S. patients received TPA at less than a third of that rate.

Low TPA use in 2000 among patients aged 80 or older in part reflected the low number of octogenarians enrolled in the trials that documented the safety and efficacy of TPA for acute ischemicstroke patients, Dr. Lin said at the International Stroke Conference, sponsored by the American Heart Association.

Data from the National Inpatient Sample included information on the treatment received by 5,932,175 patients with acute ischemic stroke at more than 1,000 U.S. hospitals during 2000-2010. The age breakdown of the nearly 6 millionpatients showed 28% were aged 18-64 years, 37% were65-79, and 35% were 80 years or older.

In 2000, medical staffs administered intravenous treatment with TPA to 1.02% of these patients aged 18-64 years, 0.92% of patients aged 65-79 years, and 0.47% of patients aged 80 or older. By 2010, the annual rates of TPA use ran 3.61% in those 18-64 years, 3.87% among those 65-79 years, and 3.55% in patients 80 years or older. In an adjusted analysis, this translated into a greater than threefold increase in TPA use among the 18- to 64-year-olds, a nearly fourfold rise in patients 65-79 years, and a nearly sevenfold jump among those 80 or older, a 24% average annual increased rate among the oldest patients, who averaged 86 years old, Dr. Lin reported.

The data also showed that among the octogenarians during 2000-2005, TPA use in women lagged behind use in men by a relative 15%, but this completely disappeared during 2006-2010, when usage rates in men and women evened out. TPA use among African Americans, Hispanics, and Asians, compared with whites, remained significantly below the rate in whites throughout the decade, although the extent of the disparity narrowed for African Americans and Asians during the second half of the decade, compared with the first half.

Dr. Lin and her associates also analyzed TPA use relative to the demographic setting of the hospital and its teaching status. During 2000-2010, the relative usage of TPA at rural hospitals, compared with urban hospitals, fell from 65% of the comparator level to 36%. Among nonteaching hospitals, the rate of TPA use dropped from 52% of the teaching hospitals’ level to 49%.

Dr. Lin said she had no relevant financial disclosures.
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