Stress is evaluated using tumour necrosis factor-alpha (TNF-alpha), Heat Shock Protein 60 (Hsp60) and other markers in chronic diseases. We examined the association of Hsp60, cortisol, TNF-alpha and interleukin-6 (IL-6) serum levels with psychological and socio-economic factors in patients with type 2 diabetes mellitus (DM-2). We studied 151 DM-2 patients in groups with <1 year and >5 years since diagnosis. Clinical data, family income and questionnaires of anxiety, depression, perceived stress, social support, glucose, glycated haemoglobin, lipids, Hsp60, cortisol, IL-6 and TNF-alpha were collected. Patients with >5 years since diagnosis of DM-2 had lower body mass index (p < 0.016), higher glucose (p < 0.005) and HbA(1c) (p < 0.005) levels. The group of recent diagnosis had higher Hsp60 (p < 0.00003). Hsp60 was associated negatively with years since diagnosis (p < 0.000012), and positively with glucose (p < 0.029). Cortisol was positively associated with glucose levels (p < 0.019) and family income (p < 0.037). TNF-alpha was associated with years since diagnosis (P < 0.004) and perceived stress (p < 0.018). At early stages of DM-2, Hsp60 increases with glucose levels, cortisol is associated with glucose levels. At later stages TNF-alpha increases, associated with perceived stress. Copyright (C) 2007 John Wiley & Sons, Ltd.