Uvulopalatopharyngoplasty : patient selection, long- term outcomes, and side effects

Abstract

Uvulopalatopharyngoplasty (UPPP) is the most common surgical treatment for adult patients with obstructive sleep apnea (OSA). Its short-term efficacy, as measured through polysomnography, is well-established and has been demonstrated in two randomized controlled trials in recent years. However, less is known about subjective sleep quality, longterm efficacy, and side effects after surgery. In addition, the reliability of the most widespread clinical test for selecting patients for surgery—the Friedman staging system—is unclear. The Friedman staging system uses a combination of tonsil size and tongue position to predict the likelihood of successful surgery.

The objective of studies I and II was to evaluate the staging system by determining its inter-examiner agreement. In study I, 15 doctors evaluated the system by using it on each other. In study II, 14 doctors evaluated the system by using it on 12 patients with OSA. Cohen’s kappa analysis was used. Kappa values of 1 represents perfect agreement, and values of 0 represent no more agreement than would have been expected through random chance. In study I, the median kappa was 0.36 for tongue position. In study II, the median kappa was 0.32 for tongue position, 0.62 for tonsil size, and 0.38 for the Friedman staging system. These findings correspond to poor agreement, indicating that the system is an uncertain method for selecting patients for UPPP.

Uvulopalatopharyngoplasty was first described in the eighties. Since then, there has been several modifications. The modified UPPP used in this thesis includes a tonsillectomy and is performed with cold instruments. It is less radical to the palate compared to the original procedure. The objective of study III was to investigate whether modified UPPP improves sleep quality by using the Functional Outcomes of Sleep Questionnaire and the Karolinska Sleep Questionnaire. The study consisted of two parts: Part 1 was a randomized controlled trial with two study groups (intervention and controls), and Part 2 was a post-operative follow-up of all patients (intervention and controls who received delayed surgery) with an analysis of outcomes at six and 24 months after UPPP. In eight out of nine subscales, there were significant improvements between the intervention and controls in favor of UPPP. In addition, at the six- and 24-month post-operative follow-ups of all patients, eight out of nine subscales were significantly improved compared to the baseline. These findings suggest a real and lasting beneficial effect of UPPP on subjective sleep quality, although a placebo effect cannot be excluded.

Previous studies have demonstrated high rates of side effects following pharyngeal surgery. The objective of study IV was to evaluate side effects and satisfaction with modified UPPP after six and 24 months. In addition, patients who reported side effects or regretted having surgery at the follow-up were contacted for an individual telephone interview approximately nine years after surgery. In our sample, the majority of patients were satisfied 24 months after surgery, despite one third experiencing side effects. Younger patients had fewer side effects than older patients. After nine years, the side effects were mostly of minor concern.

Studies on the long-term effects of UPPP are few in number, often include small study samples, and use different outcome measures and surgical techniques. The objective of study V was to investigate whether modified UPPP remained effective after eight years using polysomnography and questionnaires. In addition, the study investigated whether certain baseline factors could predict long-term outcomes. The results indicated that modified UPPP had a significant positive effect as a long-term treatment for OSA, although the effect on apnea-hypopnea index also significantly decreased over time. Daytime sleepiness, on the other hand, appeared to remain improved even in the long term. High body mass index at baseline and an increase in body mass index predicted reduced longterm outcomes.