[Determinants of C-reactive protein in individuals with very low socioeconomic status]

Low socioeconomic (SE) status has been associated to inflammation and predictors of C-reactive protein (CRP) have been investigated by studies performed in developed countries. This study aimed to identify predictors of CRP in individuals of very low SE level in a developing country and evaluate whether CRP is related to SE status in this scenario.

Eight-two individuals of very low SE level were recruited from a poor, semi-rural community in Brazil. Thirty-two individuals of high socioeconomic level comprised a comparison sample. High-sensitivity CRP was measured by nephelometry.

Eight-two individuals of very low SE level were recruited from a poor, semi-rural community in Brazil. Thirty-two individuals of high socioeconomic level comprised a comparison sample. High-sensitivity CRP was measured by nephelometry.

In the low SE individuals, independent predictors of CRP were body mass index > 25 Kg/m(2) (P<0.001), smoking (P=0.005) and acute infection conditions (P=0.049). The low SE group (median=2.02 mg/l; interquartile range 0.92 - 4.95 mg/dl) had higher CRP levels compared to the high SE group (1.16 mg/l, interquartile range 0.55 - 2.50 mg/dl, P=0.03). Body mass index tended to be higher (27 +/- 4.9 kg/m(2) vs 25.5 +/- 3.2 kg/m(2); P=0.07) and the prevalence of acute infection greater (32% vs 3%, P=0.002) in the low SE group. After overweight individuals and those with infectious conditions were excluded, the CRP levels were similar between the groups with low and high SE levels (0.93 mg/l vs 1.08 mg/l, P=0.28).

Adiposity, infection conditions and smoking are predictors of CRP in individuals with very low SE level. The first two factors determine greater level of inflammation in low SE individuals when compared to the high SE counterparts.