Article Abstract

The pattern of use and survival outcomes of a dedicated adult Home Ventilation and Respiratory Support Service in Singapore: a 7-year retrospective observational cohort study

Authors: Geak Poh Tan, Lydia Hse Yin Soon, Bin Ni, Hong Cheng, Adrian Kok Heng Tan, Ai Ching Kor, Yeow Chan


Background: In Singapore, a dedicated adult multidisciplinary Home Ventilation and Respiratory Support Service (HVRSS) was set-up to assist individuals with chronic ventilatory failure. We aimed to study the use, survival outcomes and identify factors influencing survival in our cohort of ventilator-assisted individuals (VAIs).
Methods: We retrospectively reviewed all referrals to HVRSS from 2009 to 2015. All VAIs were included and divided into 4 categories: (I) amyotrophic lateral sclerosis (ALS); (II) other neuromuscular and chest wall disease (NMCW); (III) spinal cord injury (SCI); and (IV) complex intensive care unit (ICU) groups for comparison of baseline characteristics, co-morbidities, therapy details and survival outcomes. Cox proportional analysis was used to identify important factors influencing survival for ALS and non-ALS VAIs.
Results: There were 112 VAIs; most were male (63%) and ethnic Chinese (83%). At baseline, median [interquartile range (IQR)] age was 61 [46–69] years, body mass index was 20.2 (17.1–23.8) kg/m2 and forced vital capacity was 38 [24–65] %predicted. The three most common diseases were ALS (43%), SCI (13%) and congenital muscular dystrophies (6%). Seventy-four (66%) VAIs received non-invasive ventilation (NIV). Median survival for ALS, Complex ICU, SCI and NMCW VAIs were 1.8, 2.6, 4.2 and 6.7 years respectively. In ALS, NIV conversion to invasive mechanical ventilation (IMV) was associated with longer survival [hazard ratio (HR) 0.24]. In non-ALS VAIs, older age (HR 1.40) and cardiovascular comorbidities (HR 2.61) were poor prognostic factors.
Conclusions: The HVRSS managed a heterogenous group of VAIs in Singapore and survival is comparable to published cohorts. ALS had the worst survival whereas NMCW had the best survival with Complex ICU and SCI groups in between. Transition from NIV to IMV, age and cardiovascular disease were important prognostic factors.