A posteriori dietary patterns are related to C-reactive protein levels: results from a systematic review and meta-analysis

Given the small effects of single nutrients, evaluating the relationships between cardiovascular disease risk factors and dietary patterns may be particularly useful. An increasing number of studies in recent years are investigating the association of dietary patterns with C-reactive protein (CRP) levels. This systematic review and meta-analysis examined the association between a posterioriderived dietary patterns and CRP levels in adults. PubMed and Scopus were searched for articles published up to March 2015 that examined the association of total diet and CRP levels among adults. Two independent reviewers performed the study selection, quality rating, and data extraction process. Effect sizes of eligible studies were pooled by using random-effects models. Heterogeneity was tested using I2 statistic. Overall, 16 cross-sectional and 4 case-control studies that used a posteriori approach were considered for the meta-analysis and were eligible for inclusion. The comparison of the highest and lowest categories of healthy/prudent patterns revealed a significant decrease in CRP (mean difference (MD): -0.23; 95% CI: -0.40 to -0.056; p = 0.006) when other lifestyle factors were controlled for, although there was heterogeneity in the studies. Pooled results indicated higher levels of CRP (MD: 0.16; 95% CI: 0.15 to 0.23; p  <  0.001) in the highest category of unhealthy/Western pattern compared with those in the lowest category, though there was significant heterogeneity. The results of the present meta-analysis provide evidence that a healthy/prudent pattern decreases CRP level, while adherence to unhealthy/Western pattern leads to higher level of CRP in adults.