Remodelling of biological parameters during human ageing: evidence for complexudregulation in longevity and in type 2 diabetes.

摘要

Factor structure analyses have revealed the presence of specific biologicaludsystem markers in healthy humans and diseases. However, this type of approach in udvery old persons and in type 2 diabetes (T2DM) is lacking. A total sample ofud2,137 Italians consisted of two groups: 1,604 healthy and 533 with T2DM. Ageud(years) was categorized as adults (≤65), old (66-85), oldest old (>85-98) andudcentenarians (≥99). Specific biomarkers of routine haematological and biochemicaludtesting were tested across each age group. Exploratory factorial analysis (EFA)udby principal component method with Varimax rotation was used to identify factors udincluding related variables. Structural equation modelling (SEM) was applied toudconfirm factor solutions for each age group. EFA and SEM identified specificudfactor structures according to age in both groups. An age-associated reduction ofudfactor structure was observed from adults to oldest old in the healthy groupud(explained variance 60.4% vs 50.3%) and from adults to old in the T2DM groupud(explained variance 57.4% vs 44.2%). Centenarians showed three-factor structureudsimilar to those of adults (explained variance 58.4%). The inflammatory componentudbecame the major factor in old group and was the first one in T2DM. SEM analysis udin healthy subjects suggested that the glucose levels had an important role inudthe oldest old. Factorial structure change during healthy ageing was associatedudwith a decrease in complexity but showed an increase in variability andudinflammation. Structural relationship changes observed in healthy subjectsudappeared earlier in diabetic patients and later in centenarians.