Validation of the POLY-MESAM seven-channel ambulatory recording unit

Study objectives: To determine the recording capabilities of the POLY-MESAM (PM) unit (MAP; Martinsried, Germany), an American Sleep Disorders Associa tion level III system, and to compare it with simultaneous 12-channel polys omnography in the sleep laboratory. Measurements and results: Fifty-three patients (49 men and 4 women) with ob structive sleep-related breathing disorders of varying severity were includ ed. The apnea-hypopnea indexes (AHIs) obtained using the two, methods diffe red significantly from each other, although the correlation was close. The PM unit produced false-negative results in patients with mild to moderate o bstructive sleep apnea (OSA). The sensitivity of the PM unit in detecting p atients with an AHI > 10 was 92%, while the specificity was 96.3%. Conclusions: The correlation elf AHIs obtained with polysomnography and wit h the PM unit is close. However, in some cases, the PM may underestimate OS A parameters. The PM unit produces false-negative results in patients with mild to moderate OSA. While inpatient polysomnography remains the "gold sta ndard," the PM unit may provide an inexpensive alternative in some special cases.