Association between depression and metabolic syndrome: Critical issues and missed opportunities.

Sir,

Agarwal et al.[1] described a small cross-sectional study of the metabolic syndrome (MetS) in depressed outpatients with recurrent major depressive disorder (n = 50) and bipolar disorder (n = 50). They found a significantly higher prevalence of MetS in patients relative to healthy controls (n = 50) with no significant difference between patient groups. We believe that there are critical issues and missed opportunities related to the study and the manner in which the findings were reported.

The authors do not describe the source of their healthy controls. This is important because this group, with a zero prevalence of MetS, was almost certainly nonrepresentative of the general population in India in which prevalences of 20%–34% have been reported.[23] The authors also state that they age- and sex-matched controls to cases. Matching can only be performed between two groups. When there are more than two groups, one can only perform crude group matching and hope that the matching is adequate.

The authors[1] state that recruited patients were drug-free for the past 3 months. The manner in which they have worked this assertion in both methods and discussion sections of their paper seems to suggest that patients were deliberately kept drug-free for the purpose of the study. If this is true, it is unethical. In any case, it is very unlikely that a 3-month drug-free period will reverse MetS parameters related to previous drug therapy.

The authors did not record information on a host of important variables, including age at onset of illness, number of episodes, duration of current episode, dietary habits, exercise habits, smoking, family history of MetS and components thereof, and other risk factors for MetS. The availability of this information could have allowed the authors to identify predictors or markers of MetS. The absence of this information was not acknowledged as a limitation of the study.

The authors used a wrong criterion to define MetS; the correct cut-off for blood pressure is 130/85 and not 135/80 mmHg, as the authors state.

Finally, important results were not presented, including data on each of the individual components of MetS. It would also have been useful to have data on how many patients in each group met either one or two criteria for MetS; that is, had subclinical MetS.

All in all, the study and the report thereon were characterized by many missed opportunities.

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Conflicts of interest

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