A Retrospective Study of Chinese-Specific Glabellar Contraction Patterns

Abstract

BACKGROUNDBotulinum toxin has been widely accepted as safe and effective for the treatment of glabellar lines, and previous studies have classified glabellar contraction patterns into 5 categories.OBJECTIVETo classify the glabellar contraction patterns among a large-scale Chinese population and provide a reference for injections in Chinese patients.METHODSFour hundred eighty-nine Chinese subjects who received botulinum toxin for the treatment of glabellar lines were selected for a retrospective photographic analysis of their glabellar contraction patterns. Using 2 separate previously established classification systems, the patterns were analyzed and classified by a panel of certified Chinese dermatologists.RESULTSTwo separate classification systems showed different distributions of glabellar contraction patterns among Chinese compared with Caucasians and Koreans. The classifications allowed for identification of the most frequent patterns in Chinese, which were “converging arrows” and “11” pattern, and provided references for identifying the most important muscles.CONCLUSIONBoth classification systems are applicable to the Chinese population with varying distributions. Because the classification system of de Almeida and colleagues focuses more on the muscles involved in the formation of glabellar lines, the authors' subjects classified according to this system displayed a more balanced distribution among the 5 patterns. This provides an easier reference for dermatologists in daily clinical practice and guiding treatment strategies.

Efficacy and Safety of AbobotulinumtoxinA for the Treatment of Glabellar Lines in Chinese Patients: A Pivotal, Phase 3, Randomized, Double-Blind and Open-Label Phase Study

“…Responder rates (by ILA, unless indicated) after aboBoNT-A treatment at day 30 were 89.0% in the Monheit et al (2020) study, 83.7% in Moy et al (2009), 89.5% in Brandt et al (2009), 83.7% in Carruthers et al (2002), 7.1% at day 29 in Ascher et al (2018), and 86.3% at week 4 in the Rzany et al (2006, IRA) study [ 6 , 7 , 12 , 15 , 18 , 24 ]. The higher responder rates in the current study could be due to differences in facial anatomy; for example, Chinese and Korean people possess different glabellar contraction patterns compared with Caucasian people [ 25 ]. In addition, the mass of some muscles, such as the corrugators, is often lower in Asian patients than in Caucasian patients, and the corrugators tend to be shorter, narrower, and less hyperdynamic in Asian people compared with Caucasian people, resulting in less severe glabellar lines [ 2 , 25 ].…”

“…The higher responder rates in the current study could be due to differences in facial anatomy; for example, Chinese and Korean people possess different glabellar contraction patterns compared with Caucasian people [ 25 ]. In addition, the mass of some muscles, such as the corrugators, is often lower in Asian patients than in Caucasian patients, and the corrugators tend to be shorter, narrower, and less hyperdynamic in Asian people compared with Caucasian people, resulting in less severe glabellar lines [ 2 , 25 ].…”

A Phase-III Noninferiority, Randomized Controlled Trial of Letibotulinum Toxin A for the Improvement of Moderate-to-Severe Glabellar Wrinkles in China

“…However, a noninferiority study is warranted to demonstrate the efficacy and safety of letibotulinum toxin A, a potential alternative botulinum A toxin product that may offer a cost-effective 4 and potentially more potent 6 botulinum A toxin product for consumers in China. Additionally, as classifications of glabellar wrinkles for White or Korean patients do not accurately reflect characteristics specific to the Chinese population, 1 the results from previous studies of letibotulinum toxin A for the treatment of glabellar wrinkles may not be generalizable to Chinese facial characteristics.…”

“…The use of botulinum A toxin to reduce the appearance of facial wrinkles is arguably the most popular cosmetic procedure in China, 1 providing predictable results, few adverse effects, and high patient satisfaction. 2 In aesthetic medicine, botulinum A toxin is used to weaken skeletal muscle via the presynaptic inhibition of the exocytosis of vesicles containing acetylcholine at the neuromuscular junction.…”