Late onset Pompe disease (LOPD) is an autosomal recessive neuromuscular disorder. Among the other symptoms patients are characterized by a reduction of bone mineral density (BMD) and muscle strength. Moreover there seems to be a cognitive involvement, which has not been well described yet. Therefore, the aim of this study was to assess bone, muscle, and cognitive impairments in all the members of a family affected by LOPD.

We included siblings with same genotype (p.R40X/p.N882fs) affected by LOPD. These patients underwent an experimental evaluation protocol in order to evaluate: BMD, using the dual-energy X-ray absorptiometry (DXA); muscle strength, by Hand Grip Strength Test (HGS); level of independence, using the Functional Independence Measure (FIM); cognitive functions, using Trial Making Test A (TMT-A) and B (TMT-B) and the Stroop Color Test.

Of 10 siblings with a diagnosis of LOPD, 7 (3 males and 4 females, mean aged 53.71±6.05 years) had the same genotype (p.R40X/p.N882fs). Of these 7 patients, 4 (57.14%) had low BMD values (2 osteoporotic and 2 osteopenic) and hypovitaminosis D (< 30ng/mL); two reported previous vertebral fragility fractures. The mean HGS was: 21.17±0.76kg in males and 14.50±4.58kg females. The mean FIM was 119.33±2.31 in males and 121.00±2.45 for females. Furthermore, in the neuropsychological evaluation, we found a mild attentional and executive deficit with a global cognitive framework within the normal ranges.

In this study we found low BMD values in more than half of the examined cases, a reduction of muscle strength and a mild attentional and executive deficit. These results testify the necessity of a multidimensional assessment to better investigate all the characteristics of these patients.