AMBULATORY ESOPHAGEAL PH TESTING - REFERRAL PATTERNS, INDICATION, ANDTREATMENT IN A CANADIAN TEACHING HOSPITAL

Over a 30-month period, 867 esophageal pH studies were conducted in a Canadian teaching hospital; of these, 315 tests were recorded in patie nts who were first-time referrals having no chest or upper gastrointes tinal surgery and taking no medication that would affect the results. Patients were referred by gastroenterologists, general surgeons, ENT s urgeons, thoracic surgeons, and a miscellaneous group. Patients were c lassified based on: pH results [abnormal = % total time pH < 4.0 (ie, >6.0%)], manometry (abnormal = LES resting pressure <5 mm Hg and/or ab normal peristalsis), and gender. Fifty-one percent (162/315) of the pa tient records demonstrated abnormal reflux. Intergroup comparisons of severity of reflux using two-way analysis of variance demonstrated no significant differences (P = 0.13). In the 162 patients who refluxed, 70% (N = 108) had normal motility studies; however, when the severity of reflux was compared, patients with abnormal motility (N = 54) demon strated significantly more severe reflux (19.8 +/- 12.8 vs 16.2 +/- 11 .3) P = 0.02. In those patients with abnormal manometry, no significan t differences (P = 0.44) in the severity of reflux were found among th ose with abnormal peristalsis (N = 27), low resting pressure (N = 17), or a combination of aperistalsis and low LES pressure (N = 10). Sympt omatic patients with reflux (N = 107) demonstrated a significantly gre ater percent time pH < 4.0 than those with asymptomatic reflux (N = 55 ); 18.1 +/- 11.5% vs 16.2 +/- 12.7%, P = 0.04. When the severity of re flux by gender was compared, no significant differences were found [18 .3 +/- 11.9 (male) N = 91 vs 16.2 +/- 11.9 (female) N = 71, P = 0.11]. The results from this study show that: (1) esophageal pH testing is i mportant in subspecialties other than gastroenterology and that the cl inical yield is high in all referring groups, (2) esophageal pH testin g and manometry are complimentary tests, but that reflux occurs common ly in association with normal manometry, (3) asymptomatic reflux was f ound in 34% of the patients with abnormal reflux scores, and (4) the s everity of reflux in male and female patients is similar.