Efficacy of Different Treatment Alternatives for Obesity Hypoventilation Syndrome. Pickwick Study.
BACKGROUND
The incidence of obesity hypoventilation syndrome (OHS) may be increasing in parallel with the present obesity epidemic. Despite extensive noninvasive ventilation (NIV) and continuous positive airway pressure (CPAP) use in patients with OHS, information regarding efficacy is limited.


OBJECTIVE
We performed a large, multicenter randomized controlled study to determine the comparative efficacy of NIV, CPAP, and lifestyle modification (control group) using daytime PaCO2 as the main outcome measure.


METHODS
Sequentially screened patients with OHS with severe sleep apnea were randomized into the above-mentioned groups for a 2-month follow up. Arterial blood gas parameters, clinical symptoms, health-related quality-of-life assessments, polysomnography, spirometry, 6-minute-walk distance, dropouts, compliance, and side effects were evaluated. Statistical analysis was performed using intention-to-treat analysis, although adjustments for CPAP and NIV compliance were also analyzed.


RESULTS
In total, 351 patients were selected, and 221 were randomized. NIV yielded the greatest improvement in PaCO2 and bicarbonate, with significant differences relative to the control group but not relative to the CPAP group. In the CPAP group, PaCO2 improvement was significantly different than in the control group only after CPAP compliance adjustment. Additionally, clinical symptoms and polysomnographic parameters improved similarly with NIV and CPAP relative to the control. However, some health-related quality-of-life assessments, the spirometry, and 6-minute-walk distance results improved more with NIV than with CPAP. Dropouts were similar between groups, and compliance and secondary effects were similar between NIV and CPAP.


CONCLUSIONS
NIV and CPAP were more effective than lifestyle modification in improving clinical symptoms and polysomnographic parameters, although NIV yielded better respiratory functional improvements than did CPAP. Long-term studies must demonstrate whether this functional improvement has relevant implications. Clinical trial registered with www.clinicaltrials.gov (NCT01405976).
1 San Pedro de Alcantara Hospital, Caceres, Spain.|2 Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Madrid, Spain.
Juan F
JF
Masa
1 San Pedro de Alcantara Hospital, Caceres, Spain.|2 Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Madrid, Spain.
Jaime
J
Corral
2 Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Madrid, Spain.|3 University Hospital, Burgos, Spain.
Maria L
ML
Alonso
2 Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Madrid, Spain.|3 University Hospital, Burgos, Spain.
Estrella
E
Ordax
2 Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Madrid, Spain.|4 IIS Fundacion Jimenez Diaz, Madrid, Spain.
Maria F
MF
Troncoso
5 Valdecilla Hospital, Santander, Spain.
Monica
M
Gonzalez
6 Gregorio Marañon Hospital, Madrid, Spain.
Soledad
S
Lopez-Martínez
2 Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Madrid, Spain.|7 Miguel Servet Hospital, Zaragoza, Spain.
Jose M
JM
Marin
2 Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Madrid, Spain.|8 Vall d'Hebron Hospital, Barcelona, Spain.
Sergi
S
Marti
2 Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Madrid, Spain.|9 12 de Octubre Hospital, Madrid, Spain.
Trinidad
T
Díaz-Cambriles
10 San Juan Hospital, Alicante, Spain.
Eusebi
E
Chiner
11 Araba Health Research Unit, Osakidetza, Alava Hospital, Álava, Spain.|12 Department of Medicine of Basque Country University, Álava, Spain; and.
Felipe
F
Aizpuru
2 Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Madrid, Spain.|13 Sleep Unit, Respiratory Department, Alava University Hospital IRB, Álava, Spain.
Carlos
C
Egea
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D045422:Continuous Positive Airway Pressure; D005080:Exercise Test; D005260:Female; D005500:Follow-Up Studies; D006293:Health Promotion / Q000379:methods; D006801:Humans; D057194:Intention to Treat Analysis; D008019:Life Style; D008297:Male; D008875:Middle Aged; D063087:Noninvasive Ventilation; D010845:Obesity Hypoventilation Syndrome / Q000628:therapy*; D017286:Polysomnography; D013147:Spirometry; D016896:Treatment Outcome; D055815:Young Adult
noninvasive ventilation; obesity hypoventilation syndrome; sleep apnea