Skin Intrinsic Fluorescence and Selected Measures of Visual Function and aging in Older Adults.

: Functional, structural and metabolic decline in many systems and in combination contribute to biologic aging and may be manifest as increased risk of morbid events such as neuropathy, albuminuria, and coronary artery disease or mortality. A biologic marker of aging may be a useful tool in identifying persons at increased risk of morbidity or mortality. We have measured skin intrinsic fluorescence (SIF) in a group of older adults to determine whether this easily determined measure could serve as such a biomarker.

Skin Intrinsic Fluorescence and Age-Related Macular Degeneration: The Beaver Dam Eye Study.

Purpose: To determine if skin intrinsic fluorescence (SIF), a noninvasive measure of advanced glycation endproducts and oxidative stress in skin is associated with AMD.

Methods: SIF was measured with the SCOUT DS skin fluorescence spectrometer in a cross-sectional cohort study of 969 persons aged 68 to 102 years from the 1181 who participated in the 25-year follow-up examination in the Beaver Dam Eye Study (BDES) in 2014 to 2016. The SCOUT DS skin fluorescence spectrometer uses five light-emitting diodes, centered at 375 nm to 456 nm.

Association of Skin Intrinsic Fluorescence with Retinal Microvascular Complications of Long Term Type 1 Diabetes in the Wisconsin Epidemiologic Study of Diabetic Retinopathy.

Objective: To determine the association between skin intrinsic fluorescence (SIF), a noninvasive measure of advanced glycation endproducts and oxidative stress in skin, and retinal microvascular complications of long duration type 1 diabetes, proliferative diabetic retinopathy (PDR) and macular edema.

Methods: A cross-sectional cohort study of persons with type 1 diabetes in the Wisconsin Epidemiologic Study of Diabetic Retinopathy (WESDR) who participated in a 32-year follow-up examination in 2012-2014. Subjects underwent a physical examination, answered a health questionnaire, and had fundus photographs taken.

Sex differences in the association of skin advanced glycation endproducts with knee osteoarthritis progression.

Background: The accumulation of advanced glycation endproducts in articular cartilage has been suggested as an etiologic factor in the development and progression of knee osteoarthritis (KOA).

Methods: We conducted a prospective cohort study of skin advanced glycation endproducts (sAGEs) measured non-invasively by skin intrinsic fluorescence and the relationship between sAGE KOA progression in 160 men and 287 women in a sub-cohort of the Osteoarthritis Initiative at a single site. KOA progression was measured by yearly changes in Osteoarthritis Research Society International (OARSI)-defined joint space narrowing (JSN) and by yearly changes in joint space width (JSW) from baseline to 48 months.

White matter hyperintensities in middle-aged adults with childhood-onset type 1 diabetes.

Objective: Although microvascular complications are common in type 1 diabetes mellitus (T1DM), few studies have quantified the severity, risk factors, and implications of cerebral microvascular damage in these patients. As life expectancy in patients with T1DM increases, patients are exposed to age- and disease-related factors that may contribute to cerebral microvascular disease.

Methods: Severity and volume of white matter hyperintensities (WMH) and infarcts were quantified in 97 middle-aged patients with childhood-onset T1DM (mean age and duration: 50 and 41 years, respectively) and 81 non-T1DM adults (mean age: 48 years), concurrent with cognitive and health-related measures.

Noninvasive skin fluorescence spectroscopy for detection of abnormal glucose tolerance.

The ENGINE study evaluated noninvasive skin fluorescence spectroscopy (SFS) for detection of abnormal glucose tolerance (AGT). The AGT detection performance of SFS was compared to fasting plasma glucose (FPG) and hemoglobin A (A1C). The study was a head-to-head comparison of SFS to FPG and A1C in an at-risk population of 507 subjects, with no prior diagnosis of diabetes, each of whom received a 75 g, two-hour oral glucose tolerance test (OGTT).

Advanced glycation endproducts in children with diabetes.

Objectives: To estimate skin content of advanced glycation endproducts (AGEs) by measurements of skin intrinsic fluorescence (SIF) from youth with diabetes in comparison with a population of youth and adults without diabetes.

Study Design: Using a specialized instrument, skin AGEs were estimated from skin auto-fluorescence induced at 420 nm and corrected for skin pigmentation (SIF420[kx0.5, km0.

Noninvasive skin fluorescence spectroscopy is comparable to hemoglobin A1c and fasting plasma glucose for detection of abnormal glucose tolerance.

Aim: We compare performance of noninvasive skin fluorescence spectroscopy (SFS), fasting plasma glucose (FPG), and hemoglobin A1c (A1C) for detection of abnormal glucose tolerance (AGT).

Methods: The NSEEDS trial evaluated SFS, FPG, and A1C in an at-risk population of 479 previously undiagnosed subjects from nine US centers, each of whom received a 75 g, 2 h oral glucose tolerance test (OGTT). Skin fluorescence spectra were collected and analyzed with SCOUT DS® devices.

Cross-sectional evaluation of noninvasively detected skin intrinsic fluorescence and mean hemoglobin a1c in type 1 diabetes.

Background: This study evaluated the relationship between skin intrinsic fluorescence (SIF) and long-term mean hemoglobin A1c (HbA1c) in individuals with type 1 diabetes.

Subjects And Methods: We undertook a cross-sectional analysis of 172 individuals with type 1 diabetes followed longitudinally with HbA1c data available over an average of 16.6 years.

Skin intrinsic fluorescence is associated with coronary artery disease in individuals with long duration of type 1 diabetes.

Objective: Skin intrinsic fluorescence (SIF) reflects many factors, including the presence of certain advanced glycation end products. We investigated whether SIF was associated with coronary artery disease (CAD) in type 1 diabetes and whether this relationship was independent of renal disease.

Research Design And Methods: SIF was measured in 112 subjects from the Pittsburgh Epidemiology of Diabetes Complications (EDC) study and 60 from MedStar Health Research Institute when mean age and diabetes duration were 48 and 36 years, respectively.

Skin intrinsic fluorescence correlates with autonomic and distal symmetrical polyneuropathy in individuals with type 1 diabetes.

Objective: To determine whether skin intrinsic fluorescence (SIF) was associated with autonomic neuropathy and confirmed distal symmetrical polyneuropathy (CDSP) in 111 individuals with type 1 diabetes (mean age 49 years, mean diabetes duration 40 years).

Research Design And Methods: SIF was measured using the SCOUT DM device. Autonomic neuropathy was defined as an electrocardiographic abnormal heart rate response to deep breathing (expiration-to-inspiration ratio <1.

Noninvasive optical screening for diabetes.

Background: Advanced glycation end products (AGEs) are implicated in the complications of diabetes. Advanced glycation end products also accumulate in the skin and are sensitive biomarkers for the risk of developing diabetes and related complications. Some AGEs fluoresce and can be measured noninvasively by optical spectroscopy.

Noninvasive type 2 diabetes screening: superior sensitivity to fasting plasma glucose and A1C.

Objective: This study compared the performance of a novel noninvasive technology to fasting plasma glucose (FPG) and A1C tests for detecting undiagnosed diabetes and impaired glucose tolerance.

Research Design And Methods: The design was a head-to-head evaluation in a naïve population. Consented subjects received FPG and A1C tests and an oral glucose tolerance test (OGTT).

Hemoglobin correction for near-infrared pH determination in lysed blood solutions.

The near-infrared (NIR) measurement of blood pH relies on the spectral signature of histidine residing on the hemoglobin molecule. If the amount of hemoglobin in solution varies, the size of the histidine signal can vary depending on changes in either the pH or hemoglobin concentration. Multivariate calibration models developed using the NIR spectra collected from blood at a single hemoglobin concentration are shown to predict data from different hemoglobin levels with a bias and slope.