Dyspnea assessment in myotonic dystrophy type 1

Area of Science:

• Neurology
• Pulmonology
• Medical Research

Background:

• Myotonic dystrophy type 1 (DM1) is a multisystem disorder affecting respiratory function.
• Dyspnea, or shortness of breath, is an understudied symptom in DM1 patients.
• Early identification of respiratory compromise is vital for timely ventilatory support.

Purpose of the Study:

• To multidimensionally describe dyspnea in adult DM1 patients.
• To evaluate the utility of various dyspnea assessment tools, including the mMRC scale.
• To explore the relationship between dyspnea severity and other clinical parameters in DM1.

Main Methods:

• Administered multiple dyspnea questionnaires (Multidimensional Dyspnea Profile, Visual Analogue Scale, Borg score) to 34 adult DM1 patients.
• Assessed respiratory function using Vital Capacity (VC) and six-minute walk test (6MWT).
• Compared patients with disabling dyspnea (mMRC score ≥ 2) to those without (mMRC score < 2).

Main Results:

• Most patients reported low dyspnea scores across all questionnaires.
• However, 32% of patients reported disabling dyspnea (mMRC score ≥ 2).
• Patients with mMRC ≥ 2 exhibited more severe motor impairment, lower VC, and shorter 6MWT distances compared to those with mMRC < 2.

Conclusions:

• The mMRC scale appears to be a practical tool for assessing daily living dyspnea in DM1.
• While promising, further studies are needed to confirm its role in guiding therapeutic management and ventilatory support decisions.
• Integrating the mMRC scale could improve the clinical assessment of respiratory symptoms in DM1.