Comparing Tretinoin to Other Topical Therapies in the Treatment of Skin Photoaging: A Systematic Review

Background

Many morphological and histological changes take place in aging skin. Topical tretinoin is the gold standard anti-aging agent used to reduce signs of aging through stimulation of epidermal growth and differentiation and inhibition of collagenase.

Objective

The aim of this systematic review is to summarize studies evaluating the efficacy of tretinoin compared with other topical medications and cosmeceuticals in reducing the appearance of skin aging.

Methods

A systematic review was conducted following the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) guidelines. The literature search was conducted using the PubMed and Embase databases from conception to December 2023. Studies were included if they compared anti-aging outcomes of topical medications with those of topical tretinoin (also called all-trans retinoic acid and retinoic acid). Studies were excluded if they compared non-topical anti-aging treatments with tretinoin or were conducted on animal models.

Results

The literature search resulted in 25 studies that met all inclusion and exclusion criteria. The most common study comparators to tretinoin included other forms of vitamin A. Outcomes were reported on the basis of visual reduction of aging signs, histological assessment of the epidermis and dermis, and protein expression. Although comparators to tretinoin had variable efficacy (greater in 7 studies, equivalent in 13 studies, and less in 3 studies), most studies found the comparator to be less irritating and better tolerated by patients than tretinoin.

Discussion

Tretinoin is currently the gold standard therapy for the treatment of photoaging, but its poor tolerability often limits its use. Unfortunately, given that most studies comparing topical therapies with tretinoin are of poor quality and/or demonstrate bias, there is a lack of substantial evidence to support an alternative first-line therapy. However, given there are some data to support the efficacy of retinoid precursors, namely retinaldehyde, pro-retinal nanoparticles, and conjugated alpha-hydroxy acid and retinoid (AHA-ret), these agents can be considered a second-line option for anti-aging treatment in patients who cannot tolerate tretinoin.