Inaccurate data in meta-analysis ‘Metabolic syndrome and dietary patterns: a systematic review and meta-analysis of observational studies’

Excerpt

We read with interest the meta-analysis by Rodríguez-Monforte et al. on the association of dietary patterns and metabolic syndrome (MetS) [1]. We noticed several inaccuracies regarding the inclusion of data that need to be clarified. The authors declare that the meta-analysis was conducted combining the results of MetS risk/prevalence in the highest categories of “Prudent/healthy” and “Western/unhealthy” dietary patters with the lower category (used as reference). However, checking the risk data included in the meta-analysis in more detail, we found that in the articles of Bell et al. [2] and Arisawa et al. [3] the Odds ratios referred to ‘every one standard deviation increase’ in the adherence to different dietary patterns. Furthermore, we disagree with the inclusion of risk values associated to both “Prudent/healthy” and “Western/unhealthy” dietary patterns which were calculated considering a different dietary pattern as reference (OR = 1). This inclusion in our opinion is methodologically incorrect and regarded the following cases: (1) in the articles of Sun et al. [4] and Berg et al. [5] the comparison reference was a “Healthy” dietary pattern; (2) in the article of Kimokoti et al. [6] the comparison reference was an “Empty Calorie” dietary pattern; (3) in the article of Song et al. [7] the comparison reference was a “Traditional” dietary pattern; (4) in the article of Leite et al. [8] the comparison reference was a “Common” dietary pattern. Even in the article of Duffey et al. [9] the risk associated to the “Prudent” dietary pattern was compared with the “Western” dietary pattern. We believe that such approximation is not correct and the data derived from the above reported articles [4‐9] should not have been included in the meta-analysis. …