Objective and Subjective Sleep Efficiency in Adult Patients with Cystic Fibrosis and Impact on Quality of Life

Abstract

Introduction: Poor sleep quality and excessive daytime sleepiness are common in patients with cystic fibrosis (CF), and both are negatively correlated with health-related quality of life (HRQoL). The objective of our study was to evaluate subjective and objective sleep quality in adult CF patients and its effect on HRQoL.

Materials and methods: This was a descriptive, prospective, cross-sectional study of CF patients > 18 years of age. Patients underwent nocturnal polysomnography (PSG) and were administered the Pittsburgh Sleep Quality Index questionnaire (PSQI) and the Cystic Fibrosis Quality of Life Questionnaire (CFQR 14 + Spain).

Results: The study included 23 patients, 14 women (61%). The mean age of the participants was 32 + 18 years. The mean PSQI score was 5.57 + 3.55; 13 (56.5%) of the patients were poor sleepers, and 13% reported poor sleep quality; seven (30%) had sleep latency > 30 min, 10 (43.5%) had sleep efficiency < 85%. Nineteen underwent polysomnography. According to PSG measurements, sleep efficiency was less than 90% in 61% of the patients. Pathological values were found for the following parameters: intra-sleep wakefulness in 12 patients (63%); microarousal index in 12 patients (63%); and apnea-hypopnea index (AHI) in 2 patients. The desaturation time with SpO₂ < 90% (T90) was > 30% in 3 patients. We observed a significant correlation between PSQI and all dimensions of CFQR 14.

Conclusions: Subjective and objective sleep efficiency decreases in adult CF patients. Sleep quality has an impact on HRQoL. The PSQI questionnaire was able to discriminate sleep quality.

Keywords: Airflow obstruction; Cystic fibrosis; Nocturnal hypoxaemia; Quality of life; Sleep quality.