호흡기내과 금요저널컨퍼런스 R3 박재훈 / Prof. 임효석

 Obesity & obstructive sleep apnea(OSA) ◦ linked to insulin resistance, dyslipidemia, HTN, inflammation ◦ relative causal roles is unclear ◦ weight loss  beneficial effects of cardiovascular risk factors  10% reduction in B.W  26~32% change in the apnea–hypopnea index(AHI)  The effect of CPAP combined with weight-loss intervention over the effect of each intervention alone on subclinical inflammation, insulin resistance, dyslipidemia, BP in patients with obesity and OSA

 Randomized, parallel-group, 24-week trial ◦ compared the effects of CPAP, weight loss, or both in adults with  BMI ≥30  Moderate to severe OSA  (AHI ≥15 apnea or hypopnea events/h)  CRP > 1.0 mg/L ◦ Screened with a home-based sleep monitor ◦  diagnostic polysomnography

 CPAP group & Combined-intervention group  Nightly CPAP therapy ◦ fixed-pressure or autoadjusting CPAP device (ResMed) & monitored weekly  Weight-loss group & combined-intervention group  individual weekly counseling sessions(NECP) ◦ caloric intake set  1200~1500 kcal/day (<114 kg) / 1500~1800 kcal/day (≥114 kg) ◦ Self-selected foods for first 2 weeks ◦ 3~19 weeks : more structured diet(2~3 liquid-meal replacements/day) ◦ Unsupervised exercise initiated at week 4  four 15-minute weekly sessions  four 50-minute weekly sessions by week

 Assessments ◦ at baseline, 8 weeks, 24 weeks  End point ◦ Primary  CRP ◦ Secondary  Insulin sensitivity  Dyslipidemia (TG, HDL, LDL, LDL-particle concentration) ◦ Exploratory  sBP, MAP, pulse pressure, HDL-particle concentration

 Restriction ◦ Weight loss  at least 5% of baseline weight ◦ CPAP therapy  at least 4 hours/night  at least 70% nights/total nights

-6.8kg -7.0kg

CRP level

Insulin sensitivity Dyslipidemia LDL HDL BP -14.1mmHg -6.8mmHg -3.0mmHg MAP

 Nasal or sinus congestion, nostril irritation upper respiratory symptoms ◦ 10 in CPAP group ◦ 9 in the weight-loss group ◦ 10 in the combined-intervention group  No serious adverse events occurred

 Weight loss + CPAP did not have a significant incremental effect on CRP levels  Weight loss had an incremental effect on insulin resistance and serum TG compared with CPAP, but no significant incremental effects with combination therapy  Weight loss + CPAP  larger reduction in BP

 Weight loss reduced CRP, insulin resistance, dyslipidemia, BP  CPAP monotherapy did not show a reduction in CRP and changes in insulin resistance and improve dyslipidemia  BP decreased in the CPAP, weight-loss, and combined groups ◦ both OSA and obesity have an independent causal relation to HTN

 Exclusion ◦ sham CPAP intervention ◦ no therapy group ◦ DM, mild OSA  24-week attrition rate was high(25%)  Did not assess ambulatory blood pressure

 CPAP + Weight loss did not have a significant incremental effect on CRP levels compared with either intervention alone  CPAP + Weight loss had an incremental effect on insulin resistance and TG compared with CPAP alone, but no significant incremental effects compared with the weight- loss alone  CPAP + Weight loss resulted in a larger reduction in BP than either CPAP or weight loss alone  Weight-loss is effective as a central component of the strategies used to improve the cardiovascular risk-factor profile in patients with obesity and OSA