Prognostic significance of incidental suspected transthyretin amyloidosis on routine bone scintigraphy
Olli Suomalainen, Jaagup Pilv, Antti Loimaala, Sorjo Mätzke, Tiina Heliö, Valtteri Uusitalo
Abstract
BACKGROUND: Transthyretin amyloidosis (ATTR) is an occasional incidental finding on bone scintigraphy. We studied its prognostic impact in elderly patients. METHODS: Technetium labeled hydroxymethylene diphosphonate (HMDP). ATTR was suspected in patients with ≥grade 2 Perugini grade uptake (grade 0-3). Heart-to-contralateral ratio (H/CL) of ≥ 1.30 was considered positive for ATTR. The overall and cardiovascular mortality were obtained from the Finnish National Statistical Service. RESULTS: There were a total of 1014 deaths (51%) and 177 cardiovascular deaths (9%) during median follow-up of 4 ± 2 years. ATTR was suspected in 69 patients (3.6%) of which 54 (2.7%) had grade 2 and 15 (.8%) had grade 3 uptake and in 47 patients (2.4%) by H/CL ratio. In multivariate analyses age, bone metastasis, H/CL ratio and grade 3 uptake were independent predictors of overall and cardiovascular mortality. Grade 2 uptake was a predictor of cardiovascular mortality. CONCLUSIONS: A suspected ATTR as an incidental finding on bone scintigraphy predicts elevated overall and cardiovascular mortality in elderly patients.