Effect of CPAP Therapy in Improving Daytime Sleepiness in Indian Patients with Moderate and Severe OSA

Abstract

Introduction: Obstructive Sleep Apnoea (OSA) is a highly prevalent disease and a major public health issue in India. Excessive daytime sleepiness is an almost ubiquitous symptom of OSA. Epworth Sleepiness Scale (ESS) score is a validated objective score to measure the degree of daytime sleepiness. Continuous Positive Airway Pressure (CPAP) therapy has been established as the gold standard treatment modality for OSA patients. A few Indian studies have reported the effectiveness of CPAP therapy in improving ESS scores after 1st month of CPAP use. Aim: To observe both, short-term (one month) and longterm (three month) effects of CPAP therapy on ESS scores in moderate to severe OSA patients. Materials and Methods: The patients complaining of excessive day-time sleepiness, snoring and choking episodes during sleep, consecutively presenting to medicine OPD over a period of 2 years, were subjected to Polysomnography (PSG). Seventy-three patients with apnoea-hypopnea index (AHI) ≥15 were categorised as having moderate to severe forms of OSA (moderate OSA with AHI=15-30 and severe OSA with AHI >30), and were scheduled for an initial trial of CPAP therapy. Fortyseven patients reported good tolerance to CPAP therapy after a trial period of 2 weeks and comprised the final study group. ESS scores in these patients were recorded at the baseline, and after 1st and 3rd month of CPAP therapy, and statistically analysed for significance. Results: Mean ESS score at the baseline among moderate and severe OSA patients were 13.67±2.29 and 16.56 ±1.87, respectively. ESS score in both these subgroups improved significantly to 11.63±3.79, p=0.022, CI (0.3293-4.0106)} and 14.13 ±3.74, p < 0.001, CI (1.2991-4.5408), respectively after one month of CPAP therapy. Likewise, mean ESS scores among moderate and severe OSA patients improved significantly to 9.84 ±2.97, p = 0.022, CI (0.3293-4.0106) and 12.29 ±3.97, p <0.001, CI (2.9414-6.1385), respectively after three months of CPAP therapy. Conclusion: The result of the present study shows that CPAP therapy is significantly effective in improving ESS scores in Indian patients having moderate to severe OSA. Benefits in daytime sleepiness were observed after short-term as well as long-term use of CPAP therapy.

Keywords

• epworth sleepiness scale
• hypopnea
• polysomnography