*Journal of the American Medical Association* (Vol. 299 No.
23, June 18, 2008) includes a study: “Examining a Bidirectional Association
Between Depressive Symptoms and Diabetes.”

The article is by Sherita Hill Golden, MD, MHS; Mariana Lazo, MD, MSc;
Mercedes Carnethon, PhD; Alain G. Bertoni, MD, MPH; Pamela J. Schreiner,
PhD; Ana V. Diez Roux, PhD; Hochang Benjamin Lee, MD; & Constantine
Lyketsos, MD, MHS.

Here’s how the article begins:

[begin excerpt]

The prevalence of clinical depression and presence of elevated
depressive symptoms are higher among persons with diabetes compared with
the general population. These associations may be related to
increased risk of depressive symptoms in individuals with diabetes,
increased risk of type 2 diabetes in individuals with depressive
symptoms, or both. Several but not all longitudinal studies have
reported that elevated depressive symptoms are associated with incident
type 2 diabetes. Several factors associated with depressive
symptoms, including obesity-promoting health behaviors (eg, physical
inactivity, hypercaloric diets) and activation of the
neuroendocrine and inflammatory responses (resulting in
increased cortisol, catecholamines, and cytokines), can induce insulin
resistance and the development of type 2 diabetes.

A diagnosis of diabetes or the burden of dealing with its complications
might might also lead to symptoms of depression. We previously showed
an association between prevalent depressive symptoms and treated type 2
diabetes; however, because our analysis was cross-sectional, we could
not determine the temporality of this association. Two prospective
studies of adults have shown that type 2 diabetes is associated with an
increased risk of depressive symptoms; however, several other
studies have shown no association. Other research suggested
that obesity and insulin resistance, precursors to type 2 diabetes, are
associated with a lower risk of developing depression.

[end excerpt]

Here’s how the Discussion section begins:

[begin excerpt]

These findings suggest that individuals with elevated depressive
symptoms have a modest increased risk of developing type 2 diabetes
during follow-up, independent of sociodemographic, economic, and
metabolic factors. Although this association was no longer statistically
significant after adjustment for lifestyle factors, point estimates were
largely unchanged by adjustment, suggesting that the association between
depressive symptoms and incident type 2 diabetes is not fully explained
by lifestyle risk factors. We also found that among individuals without
elevated depressive symptoms at baseline, treated type 2 diabetes was
associated with a significantly higher odds of developing depressive
symptoms during follow-up, independent of BMI, socioeconomic status, and

In contrast with the findings for treated type 2 diabetes, individuals
with impaired fasting glucose and those with untreated type 2 diabetes
had reduced risk of incident depressive symptoms, although the
association with untreated type 2 diabetes was imprecisely estimated and
did not reach our prespecified level of statistical significance due to
small numbers. In both analyses, findings were comparable across race/
ethnicity. To our knowledge, this is the first population-based study to
show a bidirectional longitudinal association between type 2 diabetes
and elevated depressive symptoms within the same cohort.

[end excerpt]

Here’s how the article ends: “The biological mechanisms by which
depression and type 2 diabetes are associated remain unclear. However,
the present study contributes to a growing body of literature indicating
a bidirectional association between these 2 serious long-term diseases.
Future studies should determine whether interventions aimed at modifying
behavioral factors associated with depressiion will complement current
type 2 diabetes prevention strategies. Finally, these findings suggest
that clinicians should be aware of increased risk of elevated depressive
symptoms in individuals with treated type 2 diabetes and consider
routine screening for depressive symptoms among these patients.”

The author note states that correspondence about the article may be sent
to Sherita Hill Golden, MD, MHS, Johns Hopkins University School of
Medicine, Division of Endocrinology and Metabolism, 2024 E Monument St,
Ste 2-600, Baltimore, MD 21205 (<sahill [at] jhmi . edu>).