Carta Revisado por pares

HIGH PREVALENCE AND EARLY COMPLICATION OF SYMPTOMATIC VERTEBRAL FRACTURE IN ELDERLY PEOPLE TREATED WITH HIGH-DOSE GLUCOCORTICOIDS

2008; Wiley; Volume: 57; Issue: 1 Linguagem: Inglês

10.1111/j.1532-5415.2009.02077.x

ISSN

1532-5415

Autores

Ichiro Tatsuno, Sawako Suzuki, Tomohiko Yoshida, Tomoaki Tanaka, Makoto Sueishi, Takao Sugiyama,

Tópico(s)

Adrenal Hormones and Disorders

Resumo

To the Editor: Glucocorticoids (GCs) are one of the drugs that cause secondary osteoporosis. In past decades, GC-induced osteoporosis has drawn considerable attention, because synthetic GC has been widely used not only in young and middle-aged patients, but also in elderly patients.1-4 The incidence of symptomatic vertebral fracture implicated in the long-term use of high-dose GC in elderly patients was investigated, analyzing a cohort at Shimoshizu National Hospital in Japan between 1986 and 2006. A total of 2,631 patients who had been mostly referred for treatment of autoimmune diseases involving multiple organs, were registered in the Chiba-Shimoshizu Rheumatic Cohort at Shimoshizu National Hospital (Yotsukaido, Japan). Those (aged ≥65) newly treated with high-dose GCs were entered into this study. They were treated with an initial dose of 20 mg prednisolone (PSL) equivalent per day for at least 6 months. GC dose-increase was defined as the re-introduction of more than 20 mg of GC per day because of greater disease activity. Symptomatic vertebral fracture was defined as vertebral deformity that was confirmed according to thoracolumbar X-ray in patients with backache. The ethics committee of Shimoshizu National Hospital approved this study. One hundred twelve patients (initial mean age±standard deviation 71.7±5.6) were followed; 59.8% were women, 21.4% used alcohol, and 22.3% smoked initially. The initial GC dose was a high 33.1±11.3 mg/d on average, and the mean daily GC dose was 18.1±10.9 mg/d. One-quarter (25.9%) required dose increases, and 8.0% required GC pulse therapy. Cumulative GC dose was estimated to be 13.5±11.1 g. Fifty-one patients (45.5%) had at least one symptomatic vertebral fracture, indicating that its incidence was high. The mean period until fracture was 20.0±25.4 months, and the number of symptomatic fractures within 12 months was 33 (29.5% in the total group, 64.7% in the fracture group). The nonsymptomatic vertebral fracture ratio with Kaplan-Meier curve progressively decreased over 1 year, being 69.6% at 12 months, 58.1% at 36 months, 51.5% at 60 months, and 48.5% at 96 months. The risk factors of symptomatic vertebral fracture were evaluated using Cox regression models, as shown in Table 1. The risk for symptomatic vertebral fracture was independently higher in female patients, with GC dose increases, and with every 10 mg/d of the initial GC dose (PSL equivalent). However, symptomatic vertebral fracture risk was independently higher with a decrease of every gram of cumulative GC dose. The high prevalence and the short incident period were characteristic in the present study, and they might be linked with the study population of elderly subjects and the GC dose used. The mean initial daily dose and daily doses were higher than those used in previous large studies.5, 6 The doses may have been high enough to produce rapid damage in the elderly bone structure. In elderly people, there are two main pathophysiological conditions to induce significant bone loss. The first is postmenopausal osteoporosis,7 and the second is known as senile osteoporosis.8 Therefore, it is possible that bone loss is frequently present, which in turn increases the risk of fracture with GC treatment in elderly people. In the current study, symptomatic vertebral fracture was demonstrated in a predominantly female-dependent manner. A plausible explanation for this sex dependence could be found in the particular composition of this elderly study population, which consisted of a majority of women, who frequently suffer from postmenopausal osteoporosis. Although it is difficult to determine the basis for the negative association between cumulative GC dose and fracture risk, there may be some genetic or environmental risk factors in the vertebral fracture group, which may shorten the duration to produce vertebral fracture and thus reduce the cumulative dose of GC. As a result, the cumulative dose might be negatively associated with fracture risk. The high prevalence of symptomatic vertebral fracture and its short incident period, as observed in elderly people, are critically important findings for considering the prevention of GC-induced osteoporosis. It recently became known that vertebral fractures associated with GC therapy are often asymptomatic.1, 9, 10 The fracture incidences observed might have been less than those that actually occurred. Because elderly patients essentially have a high risk of osteoporosis, GC treatment easily increases the fragility of bone, causing fracture from an early period. In the use of GC for elderly people, especially at high dosage, simultaneous prophylactic treatment to prevent GC-induced fracture should be considered. Conflict of Interest: The editor in chief has reviewed the conflict of interest checklist provided by the authors and has determined that the authors have no financial or any other kind of personal conflicts with this letter. Author Contributions: Ichiro Tatsuno: study concept, design and preparation of manuscript. Sawako Suzuki: analysis and interpretation of data. Tomohiko Yoshida, Tomoaki Tanaka, and Makoto Sueishi: acquisition of subjects and data. Takao Sugiyama: study concept, and acquisition of subjects and/or data. Sponsor's Role: There was no sponsor for the study.

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