Late Onset Pompe Disease (LOPD) is an autosomal recessive metabolic disorder caused by a dysfunctional enzyme (enzyme acid α-glucosidase) needed for the breakdown of complex sugars (glycogen) into shorter glucose in the cell. This leads to accumulation of glucose, especially in skeletal muscle cells, causing muscle degeneration (myopathy). Onset of the disease later in life, in juveniles or adults, usually affects proximal and respiratory muscles, with progressive respiratory muscle weakness and potential respiratory failure. This clearly has the potential to significantly affect a patient’s prognosis and quality of life.

In the study discussed in this post, the short-term and long-term effect of respiratory muscle training (RMT) for improvement of late-onset Pompe disease (LOPD) patients was explored. Improving the disease could lessen the impact it has upon the respiratory functions of afflicted individuals, and greatly improve their outlook and quality of life.

Key Findings

• Pompe disease is an autosomal recessive metabolic disorder with progressive respiratory and proximal muscle weakness, potentially leading to respiratory failure.
• 24 months of low intensity respiratory muscle training (RMT) resulted in stably maintained increased respiratory muscle strength and forced vital capacity in late onset Pompe disease (LOPD) patients.

Patient Impact

RMT can effectively slow down or attenuate respiratory muscle degeneration in people with LOPD.

Study Methods

Patients with LOPD underwent 24 months of inspiratory muscle training (IMT) with low intensity (30% of MIP) in addition to medically indicated enzyme replacement therapy. Maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) as well as forced vital capacity (FVC) were assessed at baseline and every three months.

Study Results

MIP increased significantly in response to IMT after three months and remained stable thereafter. MEP increased significantly after three months and remained stable until nine months, when it dropped to baseline levels. FVC did not change significantly from baseline levels.

RMT in combination with enzyme replacement therapy proves beneficial for LOPD patients, improving both MIP and MEP in the first year, and stabilizing MIP, MEP and FVC over the course of two years. This might be meaningful to prevent or slow long-term respiratory muscle degeneration in this patient group.

References

Ferreira JB, et al. Inspiratory muscle training reduces blood pressure and sympathetic activity in hypertensive patients: A randomized controlled trial. Int J Card 2013;166(1):61-67.