Domiciliary Diagnosis and Follow up in Obstructive Apnoea Syndrome
Condition: Obstructive Sleep Apnea
MeSH terms: Apnea; Sleep Apnea, Obstructive
Study type: Interventional

Summary: 
      The aim of the investigators study was to evaluate the effectiveness of a home programme
      (diagnosis and follow-up) in patients with Obstructive Sleep Apnea (OSA) syndrome treated
      with CPAP and to analyze the cost of this approach.
    

Detailed description: 
      The aim of our study was to evaluate the effectiveness of a home programme (diagnosis and
      follow-up) in patients with Obstructive Sleep Apnea (OSA) syndrome treated with CPAP and to
      analyze the cost of this approach.

      Detailed Description: We conducted a prospective comparative study. Patients referred for
      suspected OSAS were evaluated. In the first visit patients completed four questionnaires:
      Epworth sleepiness scale, Impact Functional Illness Questionnaire (FOSQ), activity
      questionnaire and symptom questionnaire.

      Patients were randomised to three groups:

        -  Group A (domiciliary group): home based diagnosis by home respiratory polygraphy (RP)
           and home review conducted by a specialist nurse

        -  Group B (Hospital group): hospital based diagnosis by polysomnography (PSG) and clinical
           review conducted by a Pulmonologist

        -  Group C (mixed group): home based diagnosis by home respiratory polygraphy (RP) and
           clinical review conducted by a Pulmonologist

      Following the diagnostic test (PSG or RP), patients were visited by the Pulmonologist, who
      identified the need for CPAP treatment.

      Patients were evaluated after 1,3 and 6 months of CPAP treatment. In all follow-up visits
      compliance was evaluated by objective methods and questionnaires described above were filled
      in.

      In domiciliary group, phone calls or hospital appointments were made if low compliance was
      detected or if some problem with treatment was detected.

      Instrumentation.

        -  Conventional PSG was performed in hospital supervised by a trained nurse. PSG used for
           the study was Somnostar alfa®. Parameters obtained were: electroencephalogram (C3-A2,
           C4-A1), electrooculogram electromyogram, electrocardiogram (V2 modified), respiratory
           effort by thoracic and abdominal resistance bands, air flow with nasal cannula pressure
           connected to a transducer, oxygen saturation with a pulseoximeter, and snoring with a
           selective microphone. PSG was manually interpreted in 30 seconds epochs, according to
           Rechschaffen and Kales criteria.The apnea-hypopnea index (AHI) was defined as the number
           of apneas-hypopneas divided by the number of hours of sleep. OSA diagnosis was done if
           AHI was >10 /h.

        -  Respiratory polygraphy was performed in a non-attended way in patient's home. The nurse
           who monitorized the patient in the home setting, instructed the patient on the proper
           use of the RP. A validated respiratory polygraphy system corresponding to ASDA level III
           (Stardust®) was used. The parameters monitorized were: nasal flow, chest movement,
           oxyhemoglobin saturation, pulse and body position. The same cardio-respiratory variables
           that we identified in PSG, were registered. An event rate (number of apneas + number of
           hypopnea divided by the number of hours recorded)> 15 was considered as a diagnosis. The
           study were recorded by computer system and manually interpreted by a physician. In case
           of invalid registration we performed a second PR. If in doubt after the second study a
           PSG was performed.

      Follow-up visits and assessment of compliance:

        -  Hospital monitoring group: Effective compliance was calculated by mean of the CPAP hour
           meter, dividing the total number of hours timer by the number of days of use. We
           discounted 10% of the time, which is the average time of ineffective pressure. Patients
           were considered adherent if they use CPAP at least 4 hours during 70% of the week

        -  Follow-up visits by nurses: This group of patients was treated at home through a system
           of fixed pressure CPAP (REMstar Pro, Respironics ®), with a memory card which can store
           information about the number of hours of effective pressure. It also allows to know the
           number of days of CPAP use. In all visits the nurse collect the memory card for later
           analysis, which was performed by a physician.The nurse responsible for the program
           evaluated the need of reinforcing in order to get an optimal compliance. If it was
           considered necessary, the patient was evaluated by the Pulmonologist either by mean of a
           phone call or of an hospital appointment. All patients in this group were contacted by
           phone at least once during the first month of CPAP treatment
    

Intervention name(s): Diagnosis and monitoring of OSA patients
Intervention type(s): Other
Intervention description(s): The difference between the three strategies is given by the method used for OSA diagnosis (domiciliary RP or hospital PSG) and the type of monitoring carried out after initiating CPAP treatment (by physician at hospital or by a trained nurse in patient's home)
Other intervention name(s): Domiciliary group: group A; Hospital group: group B; Mixed Group: groupC
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Supportive Care
Keywords: OSA; CPAP compliance; nurse domiciliary led; sleep disease