The Age Factor in Postbariatric Body Contouring Surgery Outcome.

BACKGROUND: Increasing life expectancy will likely lead greater numbers of older patients to seek postbariatric body contouring plastic surgery. The impact of age on body contouring plastic surgery outcome is undetermined. METHODS: A retrospective cohort study of 317 postbariatric body contouring plastic surgery cases was performed. Patient demographics and operative and postoperative data were collected. Patients were categorized into three age groups, and univariate analysis examined group differences. Multivariate logistic regression analysis assessed independent associations between age and surgical outcome measures. RESULTS: Patients 60 years and older had a higher mean preoperative body mass index (30.8 ± 3.6 kg/m2, p < 0.001) and higher rates of hypertension (48.9 percent, p < 0.001), dyslipidemia (38.3 percent, p < 0.001), and diabetes mellitus (17 percent, p = 0.012) compared to the younger age groups. They also sustained significantly higher complication rates (any minor complications, p = 0.004; minor surgical site infections, p = 0.005; minor hematomas, p = 0.007; any major complications, p < 0.001; major surgical-site infections, p < 0.001; and major dehiscence, p < 0.001). Increasing age was a significant risk factor for any major complications (p = 0.005), reoperation (p = 0.02), and readmission (p = 0.001). Age greater than or equal to 60 years was a significant risk factor solely for readmission (OR, 3.32; p = 0.03). CONCLUSIONS: Increasing age was a risk factor for adverse postoperative outcome in postbariatric body contouring plastic surgery patients; however, age greater than or equal to 60 years in and of itself was an independent risk factor for readmission only. These findings may aid plastic surgeons in patient consultation and in decision making regarding suitable candidates for these procedures. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, II.

Cryopreservation of Stromal Vascular Fraction Cells Reduces Their Counts but Not Their Stem Cell Potency.

Adipose-derived stem cells are derived from the nonfat component of adipose tissue termed the stromal vascular fraction (SVF). The use of freshly isolated autologous SVF cells as an alternative to adult stem cells is becoming more common. Repeated SVF administration for improved clinical outcomes is complicated by the need for repeated liposuction. This can be overcome by cryopreservation of SVF cells. The current study aimed to assess whether SVF cells retain their stem cell potency during cryopreservation. METHODS: SVF cells isolated from lipoaspirates (donor age: 46.1 ± 11.7 y; body mass index: 29.3 ± 4.8 kg/m2) were analyzed either immediately after isolation or following cryopreservation at -196°C. Analyses included assessment of nucleated cell counts by methylene blue staining, colony-forming unit fibroblast counts, surface marker expression using a flow cytometric panel (CD45, CD34, CD31, CD73, CD29, and CD105), expansion in culture, and differentiation to fat and bone. RESULTS: While cryopreservation reduced the number of viable SVF cells, stem cell potency was preserved, as demonstrated by no significant difference in the proliferation, surface marker expression in culture, bone and fat differentiation capacity, and the number of colony-forming unit fibroblasts in culture, in cryopreserved versus fresh SVF cells. Importantly, reduced cell counts of cryopreserved cells were due, mainly, to a reduction in hematopoietic CD45+ cells, which was accompanied by increased proportions of CD45-CD34+CD31- stem cell progenitor cells compared to fresh SVF cells. CONCLUSIONS: Cryopreservation of SVF cells did not affect their in vitro stem cell potency and may therefore enable repeated SVF cell administrations, without the need for repeated liposuction.

Fas-L promotes the stem cell potency of adipose-derived mesenchymal cells.

Fas-L is a TNF family member known to trigger cell death. It has recently become evident that Fas-L can transduce also non-apoptotic signals. Mesenchymal stem cells (MSCs) are multipotent cells that are derived from various adult tissues. Although MSCs from different tissues display common properties they also display tissue-specific characteristics. Previous works have demonstrated massive apoptosis following Fas-L treatment of bone marrow-derived MSCs both in vitro and following their administration in vivo. We therefore set to examine Fas-L-induced responses in adipose-derived stem cells (ASCs). Human ASCs were isolated from lipoaspirates and their reactivity to Fas-L treatment was examined. ASCs responded to Fas-L by simultaneous apoptosis and proliferation, which yielded a net doubling of cell quantities and a phenotypic shift, including reduced expression of CD105 and increased expression of CD73, in association with increased bone differentiation potential. Treatment of freshly isolated ASCs led to an increase in large colony forming unit fibroblasts, likely produced by early stem cell progenitor cells. Fas-L-induced apoptosis and proliferation signaling were found to be independent as caspase inhibition attenuated Fas-L-induced apoptosis without impacting proliferation, whereas inhibition of PI3K and MEK, but not of JNK, attenuated Fas-L-dependent proliferation, but not apoptosis. Thus, Fas-L signaling in ASCs leads to their expansion and phenotypic shift toward a more potent stem cell state. We speculate that these reactions ensure the survival of ASC progenitor cells encountering Fas-L-enriched environments during tissue damage and inflammation and may also enhance ASC survival following their administration in vivo.