Acanthosis nigricans in middle-age adults: A highly prevalent and specific clinical sign of insulin resistance.

BACKGROUND: Insulin resistance (IR) precedes the diagnosis of many metabolic and non-metabolic illnesses, including type 2 diabetes mellitus (T2DM). Acanthosis nigricans (AN) is a clinical sign associated with IR. However, AN prevalence and diagnostic accuracy in middle-age adults before or at the time of prediabetes/diabetes diagnosis remain uncertain. METHODS: With the aim to define AN prevalence and diagnostic accuracy, adults between 40 and 60 years of age were consecutively invited to participate in the study. Participants were categorised into one of two main groups: individuals with normoglycaemia (group 1) and hyperglycaemia (group 2 [ie, prediabetes/diabetes]). Demographic, clinical, anthropometric characteristics, homeostasis model assessment of IR, homeostatic model assessment of ß-cell function, as well as the presence of AN on the neck, axillae, elbows and knuckles were assessed. RESULTS: A total of 320 consecutive participants with a mean age of 49.3 years (59.4% women) were included. Overall, AN prevalence was 46.3%, while AN in group 1 and group 2 was 36.3% and 49.6%, respectively (P = .04). The most common affected sites in group 1 (n = 80) were the knuckles (21.2%) and the neck (17.5%), while in group 2 (n = 240), the neck (29.6%) followed by the knuckles (26.7%). The specificity and positive predictive value of AN for IR were 0.85 and 0.86 in group 1 and 0.90 and 0.96 in group 2, respectively. CONCLUSIONS: In middle-age adults, within the entire spectrum of carbohydrate tolerance, AN is highly prevalent and specific. This finding supports its assessment as a reliable and convenient clinical sign of IR. The understanding of AN behaviour through different carbohydrate tolerance strata, and its different locations, could lead to early detection of individuals at high metabolic risk or help direct a more pathophysiological treatment approach in patients with T2DM.

Weight changes in adults with major depressive disorder: A systematic review and meta-analysis of prospective studies.

BACKGROUND: Major Depressive Disorder (MDD) and obesity are bidirectionally related, but the amount of weight-gain secondary to MDD is unknown. We aimed to estimate the adjusted effect of MDD on weight-change in prospective studies compared to individuals without MDD. METHODS: Scopus/MEDLINE, PsycInfo, Web of Science and Cochrane were systematically searched for prospective observational studies of participants with a diagnosis of MDD. We included studies that conducted regression analyses on weight-variables. We searched for weight-variables reported at baseline, follow-up, and regression analyses. A meta-analysis of the odds ratios reported in logistic regression models was performed using the generic inverse weight variance method. RESULTS: Eight studies were included with a total of 60,443 subjects; 56.8 % with MDD. Weight-variables included weight, BMI, waist circumference, fat mass, and obesity incidence. In three follow-up reports, weight-variables increased more in participants with MDD and its subphenotypes than in control subjects, except for one MDD subphenotype. Meta-analysis of three eligible studies (n = 21,935) showed a significantly greater likelihood of incident obesity in participants with MDD (OR:1.48, 95%CI 1.03-2.13). MDD subphenotype reports might suggest a greater risk for atypical MDD. LIMITATIONS: Heterogeneity in weight related variables, follow-ups, and regression models; scarcity of follow-up data; and limited studies eligible for meta-analysis. CONCLUSIONS: Despite previous associations between MDD and obesity, current prospective evidence on MDD related weight-change is scarce and heterogeneous. Our findings suggest a need to standardize weight-change assessment in MDD trials. Moreover, careful weight tracking and management should be incorporated in clinical settings. PROSPERO registration CRD42020214427.

Acanthosis nigricans in the knuckles: An early, accessible, straightforward, and sensitive clinical tool to predict insulin resistance.

Any clinical/biochemical marker revealing obesity or diabetes before their appearance is valuable. Insulin resistance (IR) is present in both disorders many years before occurrence. Accordingly, we determined whether acanthosis nigricans (AN) in the knuckles is associated to higher insulin and homeostasis model assessment for estimated insulin resistance (HOMA-IR) index values, and assessed the influence of body-mass index (BMI) and the diagnostic performance of AN in the knuckles to detect IR. In this cross-sectional controlled study, we included men or women, 18 to 23 years old, with or without AN in the knuckles. In 149 cases with AN in the knuckles and 145 controls, fasting insulin was higher in cases (13.45 µU/mL ± 7.8 vs. 8.59 µU/mL ± 3.63, P < .001, respectively). Mean HOMA-IR index was also higher (2.86 ± 1.68 vs. 1.78 ± 0.77, P < .001). A significant increase in fasting insulin and HOMA-IR values between and within BMI groups from normal through obese category was identified in controls and cases. By multivariate regression analysis, cases with normal BMI were significantly associated to a HOMA-IR ≥2.5 (OR = 3.09, CI95% = 1.75-5.48, P = .001). A model of AN in the knuckles, normal BMI, and increased waist circumference allowed identifying 2 out of 3 cases with HOMA-IR index ≥2.5. AN in the knuckles could be addressed with two aims: as an easy, accessible, and costless diagnostic tool suggesting hyperinsulinemia secondary to IR, and, an early marker of IR even in the absence of overweight or obesity.

Participants' perception of pharmaceutical clinical research: a cross-sectional controlled study.

BACKGROUND: There is scarce scientific information assessing participants' perception of pharmaceutical research in developed and developing countries concerning the risks, safety, and purpose of clinical trials. METHODS: To assess the perception that 604 trial participants (cases) and 604 nonparticipants (controls) of pharmaceutical clinical trials have about pharmaceutical clinical research, we surveyed participants with one of four chronic diseases from 12 research sites throughout Mexico. RESULTS: Participation in clinical trials positively influences the perception of pharmaceutical clinical research. More cases (65.4%) than controls (50.7%) perceived that the main purpose of pharmaceutical research is to cure more diseases and to do so more effectively. In addition, more cases considered that there are significant benefits when participating in a research study, such as excellent medical care and extra free services, with this being the most important motivation to participate for both groups (cases 52%, controls 54.5%). We also found a sense of trust in their physicians to deal with adverse events, and the perception that clinical research is a benefit to their health, rather than a risk. More controls believed that clinical trial participants' health is put at risk (57% vs 33.3%). More cases (99.2%) than controls (77.5%) would recommend participating in a clinical trial, and 90% of cases would enroll in a clinical trial again. CONCLUSION: Participation in clinical trials positively influences the perception that participants have about pharmaceutical clinical research when compared to nonparticipants. This information needs to be conveyed to clinicians, public health authorities, and general population to overcome misconceptions.