Pompe & Pain - Study to Assess Nociceptive Pain in Adult Patients With Pompe Disease

Beck depression inventory fast screen questionnaire to detect severe depression for eligibility.

Validated questionnaire for pain.

German Pain Inventory questionnaire for evaluation of pain. Module A, abbreviated questions of module S (sociodemographic questions S1, S2, S3, S4, S5 and S8) and module L (quality of life) and V (therapies) will be used.

Validated questionnaire for perceived fatigue

validated questionnaire to assess a patient's functional ability and level of handicap

The R-PAct scale is designed specifically for Pompe disease, which consists of 18 items addressing daily life activities with three response options.

An evaluator observes the performance of a patient and scores the items separately on a 5-point ordinal scale (ranging from 0 to 4). A total score is obtained by adding the scores of all items and ranges between 0 and 64 points.

To ensure a high level of objective measurement, muscle strength will also be assessed by handheld dynamometry. The following muscle groups will be tested: Arm abduction, elbow flexion, elbow extension, hip flexion, hip extension, knee extension, knee flexion, foot extension, foot flexion.

It is a sub-maximal exercise test used to assess aerobic capacity and endurance. The distance covered over a time of 6 minutes is used as the outcome by which to compare changes in performance capacity. If a six-minute-walk-test was performed within the last 3 months within the routine treatment, no additional test will be performed and the distance walked in meters as well as borg scale will be recorded in the study CRF, including the date of the assessment. If not performed within the last six months, a six-minute-walk test will be performed once.

"For diagnosis of myofascial pain, pressure algometers are designed and conventionally used to measure deep pressure pain thresholds or tenderness resistance (Park, Kim et al. 2011), and the reliability of pressure pain thresholds according to raters or measurement frequencies has been proven to be relatively high (Chung, Um et al. 1992). The threshold is then determined as the arithmetic mean of the 3 series (in kPa). The measurement will be stopped immediately as the patient feels sensations of burning, stinging, drilling or aching. Pressure algometry measurements will be performed on the trapezius, deltoid and supraspinatus muscles, the rectus femoris muscles, and the tibialis anterior muscles."

Muscle ultrasound is an ideal imaging modality that allows for atraumatic, noninvasive, radiation-free point-of-care neuromuscular imaging. Muscular diseases are typically associated with an increase in the echogenicity from the muscle substance, distal attenuation of muscle echo and a corresponding loss of bone echo. A measurement on both sides deltoid, biceps and triceps brachii muscle, quadriceps femoris muscle, tibialis anterior muscle, rectus abdominis muscle and paravertebral muscles of cervical (C5-7), thoracic (Th4-6) and lumbar (L4-5) muscles. Muscle tissue alterations will be classified using the Heckmatt scale I-IV, describing muscle echogenicity. For muscle ultrasound, a linear 17MHz probe will be used. The muscle ultrasound assessment usually takes 15-20 minutes.

Vital signs (blood pressure, heart rate, respiratory rate) will be measured before and after the six-Minute-Walk-Test (6MWT).

The Borg scale will be assessed, which is a self-reported questionnaire designed to subjectively assess dyspnea and exertion during activity (Borg 1982). The Borg scale rates dyspnea on a scale of 0 to 10 incorporating nonlinear spacing of verbal descriptors of the level of intensity of dyspnea. A higher Borg score indicates more severe dyspnea. The Borg scale will be administered before starting the 6MWT (≤ 5 minutes) and after completing the 6MWT (≤ 5 minutes).

CK-Level assessment in peripheral blood (peripheral venous blood draw)

Vitamin D Level in peripheral blood (peripheral venous blood draw)

calcium level in peripheral blood (peripheral venous blood draw)

magnesium level in peripheral blood (peripheral venous blood draw)

phosphate level in peripheral blood (peripheral venous blood draw)

peripheral venous blood draw for genetic analysis of ACE polymorphism

peripheral venous blood draw for genetic analysis of ACTN3 polymorphism

"Optionally, upon additional informed consent, exome sequencing from peripheral blood will be performed in a second step to assess whether polymorphisms or pathogenic mutations in genes that are associated with chronic pain syndromes contribute to increased pain. This analysis will be performed collectively after enrollment is complete by the Genetikum Neu-Ulm. The selection of the genes is based on the Human Phenotype Ontology (HPO) search terms myalgia, muscle pain, chronic pain, musculoskeletal pain, pain, and nociceptive pain."