One of the major challenges in treating obstructive sleep apnea (OSA) is to achieve adequate continuous positive airway pressure (CPAP) adherence. Telemonitoring has the potential to provide individualized management and early recognition of problems during treatment.What is the effect of a multimodal telemonitoring intervention on treatment adherence, quality of life and functional status in symptomatic OSA patients with low cardiovascular risk?and Methods: In a multicenter, randomized controlled trial, newly diagnosed OSA patients were randomly assigned to multimodal telemonitoring for 6 months versus usual care (UC). Telemonitoring consisted of built-in electronic alert algorithms for early adjustment of CPAP treatment in case of side effects, leaks or persistent residual events. The primary outcome was CPAP adherence (in hours/night). Secondary outcomes included daily symptoms such as fatigue and sleepiness, and quality of life measured by self-reported questionnaires.Of 206 OSA patients aged 50.6 [42.1 ; 58.1] (median [IQR]) years; predominantly male (63%) with body mass index of 30.6 [26.8 ; 35.1] kg/m2 and an apnea-hypopnea index of 45.2 [34.0 ; 60.0] events/hour) 102 received UC and 104 telemonitoring. After 6 months of treatment, CPAP adherence was similar in the two groups when assessed either by mean duration of usage (4.73 ± 2.48 hours/night in the TM group and 5.08 ± 2.44 hours/night in the UC group, p = 0.30) or in % of patients adherent to treatment (over 4 hours usage/night, > 70% nights; 64% in TM versus 72% in UC, p = 0.24). There was no significant difference between the groups in effect size of improvement in fatigue and sleepiness.In severe OSA patients with low cardiovascular risk, multimodal telemonitoring did not increase CPAP adherence. For both telemonitoring and usual care groups similar improvements in daytime symptoms were achieved. NCT: 01796769.