Difference between the biologic and chronologic age as an individualized indicator for the skincare intensity selection: skin cell profile and age difference studies

Abstract

Background: The present research addresses the issue of skin aging and corresponding skin treatment individualization. Particular research question was on the development of a simplified criterion supporting patientspecific decisions about the necessity and intensity of skin treatment. Basing on published results and a wide pool of our own experimental data, a hypothesis is formulated that a difference between biologic and chronologic age can be used as a powerful indicator of skin aging. Methods: In the present paper, we report the results of studies with 80 volunteers between 15 and 65 years of age linking skin cell profile parameters to biologic and chronologic age. Biologic age was calculated using the empirical expressions based on the forced vital lung capacity, systolic blood pressure, urea concentration, and blood cholesterol level. Epidermis and derma cellular structures were studied using skin biopsy samples taken from the gluteal region. Results: The present study supports the conclusion that biologic and chronologic age difference is changing in the progress of life. Our studies are showing that time point when calculated biologic age becomes equal to the chronologic one reflecting the onset of specific changes in the age dependencies of experimentally measured skin cell profile parameters. Thus, it is feasible that a difference between chronologic and individually assessed biologic age indeed reflects the process of skin aging. Conclusions: With all reservations to the relatively small number of study participants, it seems feasible that a difference between biologic and chronologic age can be used as an indicator of skin aging. Additional research linking blood immune profile and skin topography to the difference of biologic and chronologic age (reported in the following paper) provides further support for the formulated hypotheses. So, a difference between calculated biologic age and chronologic age can be used as an individualized criterion supporting decisions on skin treatment strategies. Further research involving larger numbers of participants aimed at optimizing the expressions for calculating biologic age could lead to reliable and easily available express criterion supporting the decision for the individualized skin treatment.

Difference between the biologic and chronologic age as an individualized indicator for the skin care intensity selection: skin topography and immune system state studies, parameter correlations with age difference

“…Basing on a study of calculated biologic age for individuals with the same chronologic age and significant difference of BA and CA, it was found that a pace of aging is increasing with increasing chronologic age. Our studies indicate that there is a noticeable and measurable difference in many parameters reflecting the state of human skin for the individuals with BA < CA and BA > CA (Sukhovei et al 2019).…”

“…Here, we report on the data analysis and the most representative results for the parameters reflecting skin state and roughness, and blood immune status followed by the discussion on correlations of studied parameters with age difference BA -CA, and correlations of the skin roughness parameters with other measured skin and blood immunology status parameters. The age dependencies of the skin cell profile parameters were analyzed in a previous paper (Sukhovei et al 2019), and it was concluded that plotting the values against the difference between biologic and chronologic age allows to clarify certain tendencies and illustrate the trend changes around BA = CA. Thus, it was of significant interest to analyze if similar tendencies will be present for the blood immunology and skin roughness parameters.…”

“…where FVC is the forced vital lung capacity (liter) measured using common medical spirometer, SBP is systolic blood pressure (mm Hg) measured by a cuff tonometer, UC is urea concentration in urine (mg/100 ml), and BCh is a blood cholesterol level (mg/100 ml) and BCa is a calcium level (mg/100 ml) in the blood serum. Corresponding expressions for BA calculations are common for gerontology and age-related studies in Russia (Voitenko and Tokar 1983;Beloserova 2006;Sukhovei et al 2019). Note that these expressions give overestimated values of BA for early age and underestimated for late age, compared to the corresponding expressions used by other researchers underestimating BA in early age and overestimating it at late age (Webster and Logie 1976;Dean 1986;Borkan and Norris 1980;Dean 1998).…”

“…According to the formulated hypothesis, one should be able to select the individuals that "should not need skin corrective intervention" and "may require intensive corrective intervention." Following this approach, we have identified three sub-groups for each sex corresponding to "early age," "critical age," and "late age" as reflected by the age difference BA − CA (Sukhovei et al 2019). A group for "critical age" was defined as having this difference less than 5 years:…”

“…In addition, it was concluded that corresponding biologic age value could be calculated using a simplified approach demanding only basic parameters that could be acquired from tests performed ambulatory or in almost every clinic. Discussed results of experimental studies on dependencies of the parameters reflecting skin state (cellular structure) and their correlations with the biologic and chronologic age difference (BA − CA) provided certain grounds for the validity of such hypothesis (Sukhovei et al 2019). Basing on the available data, it was concluded that for stated purposes gender-specific expressions for calculating biologic age should be used.…”