Impact of diagnosis and treatment of obstructive sleep apnea syndrome (OSAS) with non-invasive ventilation (NIV)

Abstract

OSAS is a serious public health problem. This study attempted to measure the benefits of one year of treatment with NIV in patients with moderate-severe OSAS, as well as the economic impact for both the patient and the Portuguese National Healthcare System (NHS). Specifically, we tried to assess if the treatment with NIV reduces: daytime sleepiness; road traffic accidents; number of hospitalizations; number of days of hospitalization; number of emergency visits; number of medical specialty consultations; and respective costs. We studied all patients with moderate-severe OSAS who visited the Pulmonology Services of the Local Health Unit of Alto Minho (ULSAM) and used NIV for at least one year. To assess outcomes and costs, we used the Epworth Sleepiness Scale and the Homogeneous Diagnostic Groups (HDG’s) approved by law and contracted between the ULSAM and the NHS. Statistical data analysis was conducted by using descriptive and inferential techniques ( t -test for paired samples and Spearman’s correlation coefficient), with a significance level of 5%. Patients with mild OSAS, weight reduction, subject to otolaryngology surgery and without one year of NIV treatment were excluded from the study. The sample consisted of 153 individuals, 20.9% female and 79.1% male between the ages of 33 and 90. Our results show a significant reduction in daytime sleepiness ( p < 0.001), road traffic accidents ( p < 0.001), number of emergency visits ( p < 0.001), number of hospitalizations ( p < 0.001), and number of hospitalization days ( p < 0.001). They also reveal a significant reduction in emergency costs ( p < 0.001) and medical specialty consultations ( p < 0.001) for the patient, as well as in emergency ( p < 0.001) and hospitalization costs ( p < 0.001) for the NHS. There was no significant reduction on the number of medical specialty visits ( p = 0.269) and costs to the NHS ( p = 0.269). The results were also not significant with regard to the relationship between the severity of OSAS and the number of road traffic accidents and daytime sleepiness. Treatment of OSAS with NIV, even in the short time period of one year, reduces the use of health services and associated costs, as well as daytime sleepiness and road traffic accidents. It was also found that the value of HDG’s medical hospitalization for OSAS contracted between ULSAM and NHS was insufficient, compared to HDG’s medical hospitalization for the same pathology as defined by law, which represents an added burden for the health institution. To the Local Health Unit of Alto Minho, Portugal (ULSAM), who made possible this study with real data of their patients.