Respiratory Trajectories and Correlation with Serum Biochemical Indices in Spinal and Bulbar Muscular Atrophy

first_pagesettingsOrder Article Reprints Open AccessArticle Respiratory Trajectories and Correlation with Serum Biochemical Indices in Spinal and Bulbar Muscular Atrophy by Federica Ginanneschi *,Caterina Bigliazzi,Flora Anna Cimmino,Stefania Casali,Pietro Pelliccioni,Emanuele Emmanuello,Elena BargagliORCID andNicola De Stefano Department of Medical, Surgical and Neurological Sciences, University of Siena, 53100 Siena, Italy * Author to whom correspondence should be addressed. Brain Sci. 2024, 14(11), 1057; https://doi.org/10.3390/brainsci14111057 Submission received: 4 September 2024 / Revised: 22 October 2024 / Accepted: 24 October 2024 / Published: 25 October 2024 (This article belongs to the Section Neuromuscular and Movement Disorders) Downloadkeyboard_arrow_down Browse Figures Versions Notes Abstract Background/Objectives: The primary life-threatening complication in spinal–bulbar muscular atrophy (SBMA) is ventilatory failure. The present study analyzes the longitudinal patterns of respiratory function tests over a follow-up of 11 years. Methods: We collected data from 9 genetically confirmed SBMA patients. Spirometric measurements [maximum inspiratory pressure (MIP), maximum expiratory pressure (MEP), and forced vital capacity (FVC)], serum biochemical indices and SBMA functional rating scale (SBMAFRS) were collected every 6 months for 11 years. An average time curve was utilized to assess the changes in both pulmonary tests and serum biochemical indices of the patients. One-way repeated-measures ANOVA was applied to assess statistical differences. The Spearman’s rank correlation coefficient was utilized to evaluate the correlations between the respiratory function tests and serum biochemical and clinical indices. Results: A progressive decrease was observed in the respiratory function tests; the slope of the linear regression was significantly non-zero (p < 0.0001) for all three time curves. A major decrease was observed for MEP (52%) and MIP (42%), while this was minor for FVC (25%). SBMAFRS score correlated with FVC (r = 0.27), MIP (r = 0.53) and MEP (r = 0.51). MIP and MEP correlated with creatine phosphokinase (r = 0.3, r = 0.25, respectively) and MIP with creatinine levels (r = 0.31). Conclusions: This longitudinal study shows a progressive decline of spirometric data throughout life in SBMA patients. The decline appears to be related to clinical deterioration and muscle denervation. Spirometric measures relative to maximal strength of the respiratory muscles (MIP and MEP) may have a better predictive value for pulmonary and muscular decline than FVC.