ABSTRACT
In this systematic review, we summarize the efficacy and safety of intradermal and intramuscular botulinum toxin injections for androgenic alopecia (AGA). Using PubMed, we conducted a literature search up to February 2021 using the following keyword combinations: "botulinum toxin" or "botox" and "androgenetic alopecia," "hair loss," or "alopecia." Five clinical studies met our inclusion criteria: 4 prospective cohorts and 1 randomized clinical trial (RCT). Study durations ranged from 24 to 60 weeks. No studies included control groups or compared botulinum toxin injections against approved treatments. A total of 165 participants were identified - all of whom were males with AGA. Of the 4 studies measuring response rates (i.e., subjects with >0% hair changes), response rates ranged from 75 to 79.1%. Within studies measuring hair count changes from intramuscular injections, changes ranged from 18 to 20.9%. No serious adverse events were reported. Studies on botulinum toxin injections have produced favorable outcomes for AGA subjects. However, results should be interpreted with caution due to the absence of control groups, small numbers of participants, and relatively low Jadad quality scores. Large RCTs are recommended to confirm efficacy and safety, explore the effects of botulinum toxin on females with pattern hair loss, and establish best practices for intradermal and intramuscular injection methodologies.
ABSTRACT
INTRODUCTION: Microneedling (MN) is a minimally invasive procedure involving the induction of percutaneous wounds with medical-grade needles. In this literature review, we investigate clinical data on MN for the treatment of hair loss disorders. METHODS: A literature search was conducted through PubMed up to November 2021 to identify original articles evaluating the use of MN on hair loss disorders. The database was searched using the following keywords: "microneedling," "micro needling," "micro needle," "microneedle," "needle," "dermaroller" and "alopecia," "hair loss," "alopecia," "areata," "cicatricial," or "effluvium," RESULTS: A total of 22 clinical studies featuring 1127 subjects met our criteria for inclusion. Jadad scores ranged from 1 to 3, with a mean of 2. As an adjunct therapy, MN improved hair parameters across genders and a range of hair loss types, severities, needling devices, needling depths of 0.50-2.50 mm, and session frequencies from once weekly to monthly. Across 17 investigations totaling 911 androgenic alopecia (AGA) subjects, MN improved hair parameters when paired with 5% minoxidil, growth factor solutions, and/or platelet-rich plasma (PRP) topicals, or when introduced to subjects whose hair count changes had plateaued for ≥ 6 months on other treatments. Across four investigations on 201 alopecia areata (AA) subjects, MN improved hair parameters as a standalone therapy versus cryotherapy, as an adjunct to 5-aminolevulinic acid and photodynamic therapy, and equivalently when paired with topical PRP versus carbon dioxide laser therapy with topical PRP. Across 657 subjects receiving MN, no serious adverse events were reported. CONCLUSIONS: Clinical studies demonstrate generally favorable results for MN as an adjunct therapy for AGA and AA. However, data are of relatively low quality. Significant heterogeneity exists across interventions, comparators, and MN procedures. Large-scale randomized controlled trials are recommended to discern the effects of MN as a standalone and adjunct therapy, determine best practices, and establish long-term safety.
ABSTRACT
Despite decades of study, debate persists over the role of inflammation, fibrosis, and prostaglandins in the histopathology of androgenic alopecia (AGA). This brief review proposes that inconsistent findings across histological studies are a consequence of three inadequately controlled variables: 1) biopsy location, 2) hair diameter diversity (HDD), and 3) relative hair follicle miniaturization (HFM) within and across subjects. We suggest new methodological considerations to improve AGA histopathological research, as well as a novel classification system to quantify HFM by its stages. Finally, we hypothesize a dynamic relationship between inflammation, fibrosis, and prostaglandin activity dependent on relative HFM.
ABSTRACT
Chronic kidney disease requires a complex array of treatment interventions, including dietary and fluid restriction, medications, and self-monitoring of blood pressure. Patient well-being is directly linked to adhering to physician recommendations and treatment schedules. While considerable efforts have been directed to understanding the contribution of patient characteristics, burden of treatment, and patient-provider relations, little study has been conducted on the "system" requirements that support good patient-provider communication. This study examines how operational characteristics occurring at the time of an encounter affect the likelihood a patient will "hear" provider recommendations.
