Raised CRP levels in obese patients: symptoms of depression have an independent positive association.
BACKGROUND
Depression and obesity, the two common ailments of modern society, are associated with increased risk of coronary artery disease and raised C-reactive protein (CRP) levels. Are the effects of depression and obesity related or do they influence CRP levels independently?


OBJECTIVE
In 493 consecutive patients presenting for obesity surgery, we explored the relationship between symptoms of depression and raised CRP levels after controlling for confounding factors.


METHODS
Depression was measured using the Beck Depression Inventory (BDI). Confounding variables were age, gender, BMI, waist and hip measures, smoking and alcohol habits, medications, biochemical measures of the metabolic syndrome, and indirect measures of insulin resistance. General linear regression sought variables independently associated with CRP levels.


RESULTS
These patients had a BMI range from 31 to 91 kg/m2, participants age ranged from 14 to 71 years, and 76% were women. The median CRP concentration was 7.7mg/l (interquartile range: 3.9-14), 40% had an abnormally raised concentration (> 10mg/l). The mean BDI score was 17.0 +/- 9.0, indicating symptoms of moderate depression. We found five independent factors associated with raised CRP levels. In order of strength of association, these were: higher BMI (beta = 0.36, P < 0.001), female gender (beta = -0.19, P < 0.001), estrogen therapy (beta = 0.18, P < 0.001), higher BDI score (beta = 0.11, P = 0.01), and insulin resistance index (beta = 0.11, P = 0.01), and with a combined R2 = 0.24, (P < 0.001).


CONCLUSIONS
In obese patients, symptoms of depression were associated with raised CRP levels after controlling for confounding variables. Obese women on estrogen therapy are at risk of high CRP levels.
Dixon
John B
JB
Centre for Obesity Research and Education, Monash University, Alfred Hospital, Melbourne, Victoria, Australia. john.dixon@med.monash.edu.au
Hayden
Melissa J
MJ
Lambert
Gavin W
GW
Dawood
Tye
T
Anderson
Margaret L
ML
Dixon
Maureen E
ME
O'Brien
Paul E
PE
D000293:Adolescent; D000328:Adult; D000368:Aged; D002097:C-Reactive Protein / Q000378:metabolism*; D003863:Depression / Q000097:blood* / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000097:blood* / Q000523:psychology; D018709:Statistics, Nonparametric; D011795:Surveys and Questionnaires; D055815:Young Adult
D002097:C-Reactive Protein