The prevalence of gastroesophageal reflux disease in an adult, South African black population, and the association with obesity.

BACKGROUND: The aim of the study was to determine the prevalence of gastroesophageal reflux disease (GERD) in a black population in South Africa and to determine if there was any association with obesity.

METHODS: A sample of 312 black subjects was randomly selected and interviewed with a structured questionnaire (GerdQ) consisting of six questions translated into English and two of the most commonly used African languages (Zulu and Xhosa). This question-based symptom score for the diagnosis of GERD has been validated previously. Additional information about age, gender, smoking and alcohol was also obtained. All participants underwent anthropometric measurements.

RESULTS: The prevalence of GERD was more common in black females (22.9%) than black males (4.1%; P<0.0005) and in females there was no association of GERD with waist circumference, age, smoking or alcohol intake. However, the prevalence of GERD was higher in the second compared to the first quartile of Body Mass Index (BMI) (31.4% versus 11.45; P<0.05) but fell in quartiles 3 (28.6%) and 4 (20.1%).

CONCLUSIONS: GERD is more common in black females than males and in the former group its prevalence rose with increasing BMI and then decreases at BMIs exceeding 33.1. The reason for the gender differences and the inverted 'U' shaped relationship between GERD and BMI are not known and require further investigation.