Non-Invasive Ventilation (NIV) and Hypercapnia-Associated Symptoms in Amyotrophic Lateral Sclerosis (ALS)

Publication: Acta Neurologica Scandinavica

Study Authors: Dorst, J; Behrendt, G; Ludolph, AC.

Publisher: Wiley-Blackwell; Country of Publication: Denmark

“Objectives: During the course of amyotrophic lateral sclerosis (ALS), progressive weakness of respiratory muscles leads to chronic hypercapnia which causes various symptoms like sleep disturbances, daytime fatigue, and depression. Non‐invasive ventilation (NIV) improves survival and quality of life, but little is known about its effect on these specific symptoms, in particular during the later course of disease. Our aim was to evaluate the short‐ and long‐term effects of NIV on hypercapnia‐associated symptoms in ALS.

Material and Methods: We prospectively analyzed sleep disturbance, daytime fatigue, and depression using standardized scales (Pittsburgh sleep quality index [PSQI], Stanford sleepiness scale [SSS], Beck depression inventory [BDI], and Clinical hypoventilation score [CHS]) in 58 patients with NIV. Follow‐up was done every 3 months up to a maximum of 24 months.

Hypercapnia‐Associated Symptoms: Baseline values of PSQI, SSS, BDI, CHS, and ALSFRS‐R are shown in Figure 2. The majority of patients (70.3%) showed pathological results in the PSQI. The BDI revealed mild depression in n = 9 patients (15.6%), a moderate depression in n = 6 patients (10.3%), and a severe depression in n = 2 patients (3.4%). Median BDI was higher in patients with bulbar onset (11.5; 95% CI: 9.0‐18.0) than in patients with spinal onset (7.0; 95% CI: 4.0‐8.5; P = 0.011), indicating a higher incidence of depression in bulbar patients. For SSS and CHS, there are no pathological threshold values. The CHS, which comprises all known hypercapnia‐associated symptoms, was significantly higher in patients with pCO >45 mm Hg (24.0; 95% CI: 16.0‐32.0) than in patients with pCO ≤45 mm Hg (11.0; 95% CI: 9.0‐18.0).

Graph: Baseline values of scores for hypercapnia‐associated symptoms and ALSFRS‐R Colored lines mark pathological thresholds (PSQI) and thresholds for mild, moderate, and severe depression (BDI). ALSFRS‐R, amyotrophic lateral sclerosis functional rating scale; BDI, beck depression inventory; CHS, clinical hypoventilation score; PSQI, Pittsburgh sleep quality index; SSS: stanford sleepiness scale

Results: We found significant improvements of all outcome parameters except BDI within the first three months after NIV initiation. The median PSQI improved from 6.5 (95% CI: 5.0‐8.5) to 6.0 (95% CI: 4.5‐7.0; P = 0.042), the SSS from 3.0 (95% CI: 2.0‐4.0) to 2.0 (95% CI: 2.0‐3.0; P = 0.004), and the CHS from 22.0 (95% CI: 19.5‐25.0) to 18.0 points (95% CI: 12.0‐23.5; P = 0.013). Patients with bulbar and spinal onset were not significantly different, and positive effects were long‐lasting.

Conclusions: Our data show that NIV improves hypercapnia‐associated symptoms within the first 3 months after initiation in spinal as well as bulbar patients, and that beneficial effects are long‐lasting.

In summary, our data indicate that, NIV improves blood gases, quality of sleep, and daytime fatigue, confirming previous studies, beneficial effects are long‐lasting and may be preserved by adjusting ventilation times and parameters, the effects are present in patients with bulbar involvement as well, and other hypercapnia related symptoms such as morning headache, vegetative symptoms, and cognitive decline might improve as well, although further studies are needed for confirmation.”

Full text: https://onlinelibrary.wiley.com/doi/abs/10.1111/ane.13043

“Non-invasive ventilation and hypercapnia-associated symptoms in amyotrophic lateral sclerosis.” Acta neurologica Scandinavica, COPYRIGHT FEBRUARY 2019.