A Cross-sectional Comparison of Cleft Lip Severity in 3 Regional Populations

The purpose of this cross-sectional study was to compare the severity of unilateral cleft lips in populations of Asia, Sub-Saharan Africa, and Northern Africa and the Middle East. We hypothesize that severity of unilateral cleft lips shows significant variation between these populations.

Medical photographs of 780 patients with primary unilateral cleft lips treated by Operation Smile during November 2007 were reviewed. Photographs of 352 patients from Asia (China, Philippines, Vietnam, Laos, and Cambodia), 112 patients from the Middle East and North Africa (Jordan, Egypt, and Morocco), and 316 patients from Sub-Saharan Africa (Ethiopia, Kenya, and Madagascar) were analyzed. The severity of cleft lips was determined using the Fisher method, which measures the columellar angle as a deviation of the columella from its normal vertical position. The angle was measured using a protractor with its base positioned along a line joining the lateral canthi. An analysis of variance calculated statistical differences between each region and their respective countries.

The Asian region was found to have the greatest severity of unilateral cleft lip deformity (P < .05). Analysis-of-variance tests show a significant difference between Asia and other regions studied. When stratifying the data by country, the Philippines and Vietnam showed the highest severity.

The results suggest a heterogeneous pattern of global severity. Unilateral cleft lips with the highest severity were predominant in the Asian region. The observed phenotypical differences can be used in future studies of gene variability or environmental factors to determine the cause of this significant disparity.