Successful results of genioglossus advancement and hyoid myotomy with suspension (GAHM) in the treatment of obstructive sleep apnoea (OSA) have been reported. However, there have been few studies of long-term results. Forty-six patients with hypopharyngeal obstruction underwent GAHM. Patients had a mean age of 40.1 +/- 4.2 years and a mean body mass index (BMI) of 28.9 +/- 2.1 kg/m(2). The mean follow-up was 39.4 +/- 5.7 months with a range of 37 to 46 months. The mean pre-operative RDI, short-term RDI, and long-term RDI were 47.9 +/- 8.4, 14.2 +/- 3.9, 18.6 +/- 4.1, respectively. The mean post-operative LSAT, short-term LSAT, and long-term LSAT were 81.2 per cent +/- 2.9 per cent, 88.8 per cent +/- 2.7 per cent and 87.2 per cent +/- 3.1 per cent, respectively. The change in BMI was significantly different in the patients with, and without, recurrence (2.1 +/- 0.3 vs 0.4 +/- 0.2.kg/m(2), <0.05). Thirty (65.2 per cent) patients had long-term clinical success, and six (16.7 per cent) patients with short-term success failed long-term. GAHM appears to be an effective procedure and results in long-term success. However, patients with weight gain are at risk of recurrence.