Skin tags and acanthosis nigricans in patients with hepatitis C infection in relation to insulin resistance and insulin like growth factor-1 levels

Periorbital melanosis and its possible association with insulin resistance and vitamin D deficiency: A pilot case-control study

OBJECTIVE

To investigate the possible association of periorbital melanosis (POM) with insulin resistance (IR) and vitamin D serum levels.

METHODS

In this pilot, case-control study, we included 100 adult patients with POM and 100 age- and sex-matched healthy control subjects. Vitamin D levels and IR indices (i.e., homeostatic model assessment-insulin resistance [HOMA-IR], triglycerides/high-density lipoprotein cholesterol (TG/HDL-c) ratio, adiponectin/leptin (A/L) ratio) were compared between cases and controls.

RESULTS

Compared with controls, POM cases had significantly higher values of HOMA-IR and TG/HDL-c ratio, and significantly lower values of A/L and vitamin D. HOMA-IR and TG/HDL-c ratio were statistically significantly positively correlated with POM severity while Vitamin D and A/L ratio were statistically significantly negatively correlated.

CONCLUSION

POM was associated with indices of IR and vitamin D deficiency. However, the exact causal link among POM, IR, and vitamin D needs to be established. However, the results of this pilot study suggest that POM may have potential as a cutaneous non-invasive marker of these metabolic disorders which would assist in detecting and treating them at an early stage.

Assessment of Patients with Periorbital Melanosis for Hyperinsulinemia and Insulin Resistance

Background:

Periorbital melanosis (PM) is one of the most common dermatological condition seen in routine practice. Several cutaneous markers such as acanthosis nigricans have been associated with insulin resistance (IR). However, the association of PM with IR needs to be substantiated.

Objective:

The objective of the study is to evaluate the association of circulating adipokines and IR with PM.

Materials and Methods:

In this cross-sectional study, we recruited 100 patients with PM and 100 age- and gender-matched healthy controls. The serum levels of leptin, adiponectin, fasting glucose, fasting insulin, insulin-like growth factor-1 (IGF-1), homeostatic model assessment of insulin resistance (HOMA-IR), and leptin: adiponectin ratio (L/A ratio) were assayed.

Results:

The serum levels of leptin, fasting glucose, fasting insulin, HOMA-IR, L/A ratio were significantly higher in patients with PM as compared to controls. The serum levels of adiponectin were significantly lower in cases as compared to controls. On multivariate regression analysis, leptin, adiponectin, and HOMA-IR were found to be significant, even after adjusting for BMI, blood pressure and LDL and HDL cholesterol.

Conclusion:

Our findings suggest that patients with PM have hyperinsulinemia, IR, and elevated L/A ratio. PM as a marker of IR in adults may help in identifying patients early and thus aid in the early prevention and management of the disease.

An approach to acanthosis nigricans

Acanthosis nigricans (AN) is characterized by dark, coarse and thickened skin with a velvety texture, being symmetrically distributed on the neck, the axillae, antecubital and popliteal fossae, and groin folds, histopathologically characterized by papillomatosis and hyperkeratosis of the skin. A high prevalence of AN has been observed recently. Different varieties of AN include benign, obesity associated, syndromic, malignant, acral, unilateral, medication-induced and mixed AN. Diagnosis is largely clinical with histopathology needed only for confirmation. Other investigations needed are fasting lipoprotein profile, fasting glucose, fasting insulin, hemoglobin and alanine aminotransferase for obesity associated AN and radiological investigations (plain radiography, ultrasonography, magnetic resonance imaging/computerized tomography) for malignancy associated AN. The most common treatment modalities include retinoids and metformin.

Cutaneous stigmata associated with insulin resistance and increased cardiovascular risk

Certain cutaneous conditions have been reported to be associated with diabetes mellitus, insulin resistance, and metabolic syndrome. In this novel review paper, the evidence linking various cutaneous phenomena (e.g. skin tags, acanthosis nigricans, ear lobe creases, and xanthelasma) and metabolic syndrome and cardiovascular disease is examined, and explanations for these associations are proposed.