Abstract
Background: The relation between immune parameters and depression has been inconsistent, with some studies reporting immunosuppression while others reporting excessive immune responses in depressed people. This topic has not been extensively studied in the elderly, nor have researchers attempted to examine it in a non-linear manner, given previously observed contrasting findings.
Objective: To examine the non-linear relation between initial white blood cell count (WBC) and depressive symptoms among acutely hospitalized elderly people.
Methods: The investigation was designed as a cross-sectional analysis within a longitudinal study. Two-hundred and four patients aged 65 and above (60.3% men), admitted to internal medicine at the Soroka University Medical Center, Israel, were recruited for this study. Depression was assessed using the total 30-item Geriatric Depression Scale (GDS). WBC was obtained from medical records as well as demographic data, diagnoses and medications, and nutritional status was assessed also with self-report. To analyze a non-linear relation, we trichotomized WBC levels into low (< 6000), normal (≥ 6000 to ≤ 10 000) and high (> 10 000).
Results: The prevalence of depression (GDS > 10) was 26.5%. GDS scores were significantly higher among patients with low and high WBC (P < 0.005) than in patients with normal WBC levels. After adjustment for sex, education, nutritional status and diagnoses of arthritis and gastrointestinal diseases, this non-linear relation remained significant (P < 0.05). Finally, 40.5%, 17.1% and 37% of patients with low, normal and high WBC, respectively, were categorically depressed (P < 0.003).
Conclusions: Our findings suggest that depressive symptoms are associated with immunological dysregulation among hospitalized elderly patients with an acute illness. Future studies need to identify which elements of the immune system are suppressed and which are excessively active among depressed elderly people and the health consequences of this immune dysregulation.
Objective: To examine the non-linear relation between initial white blood cell count (WBC) and depressive symptoms among acutely hospitalized elderly people.
Methods: The investigation was designed as a cross-sectional analysis within a longitudinal study. Two-hundred and four patients aged 65 and above (60.3% men), admitted to internal medicine at the Soroka University Medical Center, Israel, were recruited for this study. Depression was assessed using the total 30-item Geriatric Depression Scale (GDS). WBC was obtained from medical records as well as demographic data, diagnoses and medications, and nutritional status was assessed also with self-report. To analyze a non-linear relation, we trichotomized WBC levels into low (< 6000), normal (≥ 6000 to ≤ 10 000) and high (> 10 000).
Results: The prevalence of depression (GDS > 10) was 26.5%. GDS scores were significantly higher among patients with low and high WBC (P < 0.005) than in patients with normal WBC levels. After adjustment for sex, education, nutritional status and diagnoses of arthritis and gastrointestinal diseases, this non-linear relation remained significant (P < 0.05). Finally, 40.5%, 17.1% and 37% of patients with low, normal and high WBC, respectively, were categorically depressed (P < 0.003).
Conclusions: Our findings suggest that depressive symptoms are associated with immunological dysregulation among hospitalized elderly patients with an acute illness. Future studies need to identify which elements of the immune system are suppressed and which are excessively active among depressed elderly people and the health consequences of this immune dysregulation.
| Original language | English |
|---|---|
| Pages (from-to) | 53-59 |
| Journal | Geriatrics and Gerontology International |
| Volume | 6 |
| DOIs | |
| State | Published - 2006 |