Age and cigarette smoking are independently associated with the cutaneous vascular response to local warming

To investigate the relative impacts of age and cigarette smoking on cutaneous blood flow and flow motion.

Skin blood flux was measured before and during the hyperaemic response to thermal warming of the skin to 43 degrees C using laser Doppler fluximetry (LDF) in 28 habitual smokers (5.4 [11.4] (median [IQR]) pack years; pack years = packs/day x duration of smoking habit), aged between 18 and 63 years and their age, sex and body mass index. Flow motion was assessed using Fourier analysis of the LDF signal.

Mean and total hyperaemic (area under the flux curve, AUC(10)) response during warming were reduced in smokers compared with their non-smoking controls (P<0.05). Attenuation of the response to warming in smokers was associated with a reduction in relative spectral power around 0.01 Hz, reflecting a reduced endothelial/metabolic activity (P<0.04). In regression modelling with AUC(10) as the outcome, and smoking (yes/no), age, sex and BMI, as explanatory variables, age (P<0.0001) and smoking (P=0.018) were independently associated with the hyperaemic response and together accounted for 31% of the variance in AUC(10).

Age and smoking are associated with approximately one-third of the variance in the endothelium-associated microvascular vasomotor activity in habitual smokers.