Fracture rate in patients with myasthenia gravis: the general practice research database

Abstract

SummaryThe aim of this study was to evaluate fracture risk after onset of myasthenia gravis using the UK General Practice Research Database. Overall fracture risk is not statistically increased compared with age- and gender-matched controls irrespective of glucocorticoid use, but was increased in those using antidepressants, anxiolytics or anticonvulsants.IntroductionMyasthenia gravis (MG) is a neuromuscular disease which has been associated with an increased falls risk and glucocorticoid-induced osteoporosis, recognized determinants of increased fracture risk. The aim of this study was to evaluate the risk of fracture after onset of MG.MethodsWe conducted a retrospective cohort study using the UK General Practice Research Database (1987–2009). Each MG patient was matched by age, sex, calendar time and practice to up to six patients without a history of MG and we identified all fractures and those associated with osteoporosis.ResultsCompared to the control cohort, there was no statistically significant increased risk observed in patients with MG for any fracture (adjusted hazard ratio [AHR] 1.11; 95 % confidence interval [CI], 0.84–1.47) or osteoporotic fractures (AHR 0.98 [95 % CI 0.67–1.41]). Further, use of oral glucocorticoids up to a cumulative dose exceeding 5 g prednisolone equivalents did not increase risk of osteoporotic fracture (AHR 0.99 [95 % CI, 0.31–3.14]) compared with MG patients without glucocorticoid exposure. However, fracture risk was higher in patients with MG prescribed antidepressants (AHR 3.27 [95 % CI, 1.63–6.55]), anxiolytics (AHR 2.18 [95 % CI, 1.04–4.57]) and anticonvulsants (AHR 6.88 [95 % CI, 2.91–16.27]).ConclusionOverall risk of fracture in patients with MG is not statistically increased compared with age- and gender-matched controls irrespective of glucocorticoid use but was increased in those using antidepressants, anxiolytics or anticonvulsants. These findings have implications in strategies preserving bone health in patients with MG.

Effects of alendronate and alfacalcidol on bone in patients with myasthenia gravis initiating glucocorticoids treatment

“…Limb weakness and impaired vision caused by MG itself would increase the risk of falls and therefore elevate incidence of bone fracture . In addition, a large‐scale analysis from the UK General Practice Research Database indicated that fracture risk was increased in patients with MG using antidepressant, anxiolytic or anticonvulsant drugs . However, few studies had reported the frequency of osteoporosis and fractures in patients with MG. Konno et al reported that 6.4% of patients with MG suffered from osteoporotic fractures during therapy with GCs (n = 283).…”

Association between Glucocorticoid-Induced Osteoporosis and Myasthenia Gravis: A Cross-Sectional Study

“…A retrospective cohort study using the UK General Practice Research Database revealed that overall risk of fracture in patients with MG was not statistically increased compared with age- and gender-matched controls irrespective of glucocorticoid use [ 8 ]. In contrast, the population-based retrospective cohort study from the Taiwan National Health Insurance Research database provided evidence that MG was associated with a high risk of osteoporosis regardless of glucocorticoid use [ 9 ].…”

Effects of Neurological Disorders on Bone Health

“…However, altered acetylcholine signaling may also play a role, as osteoblasts express acetylcholine receptors and elevated acetylcholine levels induce osteoblast proliferation (En-Nosse et al, 2009;Sato et al, 2010). In addition, MG patients prescribed antidepressants, anxiolytics, or anticonvulsants had increased fracture risk (Pouwels et al, 2013). The mechanism underlying this finding is unknown but may be due to altered neuronal signaling, as use of SSRIs reduces BMD in humans (Ducy and Karsenty, 2010;Haney et al, 2010;Brinton et al, 2019).…”