Relationships between physical function, systemic inflammation, and metabolic status in Swedish men and women - a longitudinal study from adolescence to old age

Sammanfattning: Abstract:Introduction: Ageing is associated with a decrease in physical capacity. However, various aspects of this phenomenon remain to be clarified. In the present project, we aimed to investigate age-induced changes in physical capacity, metabolic status, and inflammation in men and women, and to investigate potential correlations between physical capacity and inflammation and/or metabolic markers.Material and method: 39 men and 36 women were longitudinally evaluated at four time points at 16, 34, 52, and 63 years of age. Muscle strength was measured by functional tests such as bench press, handgrip, vertical jump, two hand lift, and curl up. The Åstrand test was performed to estimate maximal oxygen uptake (VO2max). Muscle thickness was also determined using ultrasonography. Inflammatory and metabolic blood parameters were also measured.Results: Muscle strength tended to decrease at old ages and was generally higher in men than women according to muscle function tests. At the age of 63, men displayed significantly higher muscle mass and strength compared to women. Insulin, glucose, and high-density lipoprotein (HDL) significantly increased during the period from 52 to 63 years of age. Total cholesterol, low-density lipoprotein (LDL), and HDL displayed a sex-dependent trend, as they had higher values among women. Glucose, on the other hand, was greater in male individuals. Neither time- nor sex-dependent changes were found in hemoglobin A1C (HbA1C) and/or C-reactive protein (CRP). Muscle function tests were negatively correlated with HbA1C, insulin, total cholesterol, and CRP at the age of 63. VO2max also showed negative correlations with HbA1C and insulin at the age of 52 and with glucose at the ages of 52 and 63. In other words, increased HbA1C and insulin at the age of 52 as well as increased glucose at the ages of 52 and 63 were associated with decreased VO2max.Conclusion: Alterations in physical capacity were similar between men and women during aging. High inflammatory markers (CRP), as well as dysregulated metabolic status, seem to be somewhat associated with deteriorated muscle function at old ages.