Metabolic syndrome in patients with Alopecia Areata: A case-control study

Serum lipids may causally affect the occurrence of alopecia areata: A Mendelian randomization study

PURPOSE

The etiology of alopecia areata (AA) in relation to serum lipids remains unclear, thereby prompting our intention to do Mendelian study on this subject.

DESIGN

Two-sample Mendelian randomization (MR) analysis was performed in the study. The inverse variance-weighted method was used as the primary method.

METHODS

In our study, we integrated a set of 123 single-nucleotide polymorphisms (SNPs) into our analysis. These SNPs have been extensively studied and are known to exhibit associations with serum lipids. We sourced these SNPs from a variety of relevant studies and consortia that specifically focus on lipid-related research, such as the MRC Integrative Epidemiology Unit. These carefully curated SNPs were then utilized as instrumental variables in our analysis, allowing us to explore and evaluate the causal relationships between these genetic variants and serum lipids. By incorporating this comprehensive set of SNPs, we aimed to enhance the precision and robustness of our findings, shedding light on the intricate interplay between genetics and serum lipids.

RESULTS

In the MR analysis, a higher total lipid concentration in large low-density lipoprotein (LDL) particles (odds ratio [OR] = 1.502; 95% confidence interval [CI] = 1.086-1.953; p = 0.006), a greater ratio of cholesteryl esters to total lipids in chylomicrons and extremely large very LDL (VLDL) particles (OR = 2.174; 95% CI = 1.300-2.500; p = 0.010), and a greater ratio of cholesterol to total lipids in chylomicrons and extremely large VLDL particles (OR = 2.363;95% CI = 1.556-4.438; p = 0.004), were genetically predicted to be causally associated with an increased risk of AA, while patients with a higher triglyceride to total lipids ratio in chylomicrons and extremely large VLDL particles had a lower risk of AA (OR = 0.481; 95% CI = 0.191-1.270; p = 0.002).

CONCLUSION

This study found that serum lipids may be causally implicated in AA.

Comorbid Conditions Associated with Alopecia Areata: A Systematic Review and Meta-analysis

BACKGROUND

Alopecia areata (AA) is a complex autoimmune condition resulting in nonscarring hair loss. In recent years, many studies have provided new evidence on comorbid diseases present in patients with AA. However, some studies have conflicting results, and analyses conducting a comprehensive approach are lacking.

OBJECTIVE

The aim of our study was to provide an updated systematic review and meta-analysis of medical comorbidities associated with AA.

METHODS

We searched PubMed, Embase, and Web of Science for case-control, cross-sectional, and cohort studies investigating medical comorbidities in AA published from inception through 1 February 2023.

RESULTS

We screened 3428 abstracts and titles and reviewed 345 full text articles for eligibility. Ultimately, 102 studies were analyzed, comprising 680,823 patients with AA and 72,011,041 healthy controls. Almost all included studies (100 of 102 studies) were of satisfactory to high quality (Newcastle-Ottawa scale score ≥ 4). Among patients with AA, comorbidities with the highest odds ratios (OR) compared with healthy controls and data available from more than one study included vitamin D deficiency (OR 10.13, 95% CI 4.24-24.20), systemic lupus erythematous (OR 5.53, 95% CI 3.31-9.23), vitiligo (OR 5.30, 95% CI 1.86-15.10), metabolic syndrome (OR 5.03, 95% CI 4.18-6.06), and Hashimoto's thyroiditis (OR 4.31, 95% CI 2.51-7.40). AA may be a protective factor for certain disorders, for which the AA group had lower odds compared with healthy controls, such as irritable bowel syndrome (OR 0.38, 95% CI 0.14-0.99) and colorectal cancer (OR 0.61, 95% CI 0.42-0.89).

CONCLUSION

These findings corroborate and contextualize the risks across comorbidities for patients with AA. Further work should be done to identify the underlying pathophysiology and understand appropriate screening criteria.

The frequency of fatty liver in patients with alopecia areata: A case-control study

BACKGROUND

Alopecia areata (AA) is an immune-mediated nonscarring hair loss disorder with multiple subtypes, including alopecia universalis (AU). Previous studies have shown a link between serum lipid profile and alopecia. We aimed to investigate the frequency of fatty liver in patients with AU and patchy alopecia areata (PAA) compared to a control group.

METHODS

This case-control study included patients with AU and PAA referred to a dermatology clinic from September 23, 2019 to September 23, 2020. A group of individuals without hair loss disorders attending the same clinic were selected as controls. Participants' general information, including age, sex, weight, height, and waist circumference (WC), was recorded. Body mass index (BMI) was calculated for all participants. Also, hyperlipidemia and statin use were noted and liver enzymes were evaluated. For AU and PAA patients, disease duration and the Severity of Alopecia Tool (SALT) score were also recorded. Then, all subjects underwent ultrasound to assess fatty liver and its grade.

RESULTS

Overall, 32 patients were included in each group. All three groups were comparable in age, sex, weight, height, BMI, WC, hyperlipidemia, abnormal liver enzymes, and statin use. Disease duration and SALT score were significantly higher in the AU than in the PAA group (p = 0.009 and p < 0.001, respectively). The frequency of fatty liver was the highest in AU patients (40.6%), followed by 34.4% in PAA patients, and 21.9% in controls (p = 0.263). This was also the case for grade-1 fatty liver, while grade-2 was more common in PAA patients, and grade-3 was only observed in one patient from the AU group (p = 0.496).

CONCLUSIONS

Fatty liver was more frequent in AU and PAA patients than controls, without statistically significant differences. There might be an association between fatty liver and AA, particularly the AU subtype.

The Role of Nutrition in Immune-Mediated, Inflammatory Skin Disease: A Narrative Review

Immune-mediated inflammatory skin diseases are characterized by a complex multifactorial etiology, in which genetic and environmental factors interact both in genesis and development of the disease. Nutrition is a complex and fascinating scenario, whose pivotal role in induction, exacerbation, or amelioration of several human diseases has already been well documented. However, owing to the complexity of immune-mediated skin disease clinical course and breadth and variability of human nutrition, their correlation still remains an open debate in literature. It is therefore important for dermatologists to be aware about the scientific basis linking nutrition to inflammatory skin diseases such as psoriasis, atopic dermatitis, hidradenitis suppurativa, bullous diseases, vitiligo, and alopecia areata, and whether changes in diet can influence the clinical course of these diseases. The purpose of this narrative review is to address the role of nutrition in immune-mediated inflammatory skin diseases, in light of the most recent and validate knowledge on this topic. Moreover, whether specific dietary modifications could provide meaningful implementation in planning a therapeutic strategy for patients is evaluated, in accordance with regenerative medicine precepts, a healing-oriented medicine that considers the whole person, including all aspects of the lifestyle.