0695 Residual Periodic Limb Movement Index After CPAP Titration Is Correlated with Hypoxemia

Abstract Introduction Periodic limb movement of sleep (PLMS) are commonly seen in patients with obstructive sleep apnea (OSA) . There are few studies that have assessed the persistence of PLMS in patients with OSA, treated with continuous positive airway pressure (CPAP). In the current study we analyzed PLMS outcomes in split studies and found correlates. Methods Retrospective chart review of adult patients undergoing split studies. Demographics, diagnostic and titration polysomnographic data was collected. Groups were divided in four: group 1 had normal index of PLMS ( 15) on both portions of the sleep study, group 2 had elevated periodic limb movement index (PLMI) 15, but did not change with treatment, group 3 had worse PLMI on titration, group 4 had resolution of PLMI during titration portion. Results A total of 138 patients were included (62.8% male, 37.2% female). age±SD was not statistically significant between groups, Group 1 (40.6% of patients) with mean age 56.4±14.5, group 2 (17.9%) mean age 51.3±15.6, group 3 (13.1%) mean age 65.1±12.1 and group 4 (28.3%) mean age 60.4±9.8. PLMI was different among groups (p 0.001) both during diagnostic and titration. During diagnostic PLMI Group 1 was 3.8±4.7, group 2 was 56.8±29.7, group 3 was 11.9±9.9 and group 4 was 55.5±36.8. During treatment portion PLMI group 1 was 2.6±4, Group 2 was 64.9±35.7, group 3 was 55±31.9 and group 4 was 8.9±9. None of the sleep parameters were statistically significant between groups except the time spent with saturation below 88% (p 0.05) With the normal group (1) and group 4 having the least time below 88%. Group 1: 11.5±18 minutes, group 4 spent 11.5±18 minutes. While group 2 spent 36.6±41.2 and group 3 spent 26.3±25.7 minutes. There was a moderate Pearson correlation of 0.384 (CI 0.206-0.538) between saturation time below 88% and PLMI in the titration portion. Conclusion An elevated PLMI was present in 59.4% of patients with OSA undergoing split studies. Resolved in 28.3% and worsened in 13.1%. The group with no change in PLMI (group 2) had that worse PLMI and worse hypoxemia. PLMI was moderately correlated with time spent with saturation below 88%. Support (if any)