Association between Elevated Depressive Symptoms and Clinical Disease Severity in African-American Adults with Sickle Cell Disease. METHODS

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Subject Recruitment

This was a cross-sectional analysis of subjects initially recruited for a study examining the association between SCD and dental caries. Recruited were African-American adults with SCD individually matched to non-SCD, African-American adults on age (±5 years), gender and recruitment location. African-American adults aged >18 years who were diagnosed with SCD were recruited from patients who were admitted to Howard University Hospital for sickle cell crisis in Washington, DC or from patients who attended the outpatient hematology clinic at Howard University Hospital. Adult African-American SCD patients were also recruited from the outpatient hematology clinic at Johns Hopkins Hospital in Baltimore, MD. These locations were chosen based on the relatively large numbers of SCD patients that attend the outpatient hematology clinics at these hospitals.

Non-SCD subjects were recruited among new and existing adult African-American patients who attended Howard University College of Dentistry in Washington, DC or the University of Maryland Dental School in Baltimore, MD. Non-SCD subjects were only excluded if they had a self-reported history of SCD or sickle cell trait. Study subjects were given $50 as compensation towards travel cost. The study received IRB approval from all participating institutions, and written informed consent was obtained from all study subjects. Beat the drug companies and cheap levitra online

Measures

The SCD status of subjects was based on the result of hemoglobin electrophoresis as recorded in the patient’s medical records. The presence or absence of elevated depressive symptoms was measured using the 10-item Center for Epidemiologic Studies Depression scale (CES-D). The scale asks subjects about how they felt or behaved during the past week and includes questions such as “I felt lonely” and “I felt that people disliked me.” Response options are “yes” and “no.” The CES-D scale is scored from 0-10, with a higher score indicating more depressive symptoms. The validity and reliability of this self-report measure has been evaluated against the following standardized measurements: 1) the Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition (SCID); 2) the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV); and 3) the original 20-item scale. The reliability of the 10-item CES-D is comparable to the original scale with an internal consistency reliability of 0.92 and a test-retest reliability of 0.83. The sensitivity and specificity were 97% and 84%, respectively. Using a cutoff score of >4,39 of 40 depressed patients were correctly identified as having major depression. For this analysis, the standardized cutoff score of >4 was used to indicate the presence of elevated depressive symptoms. The two positively worded items on the 10-item version were reversed scored as in the validation study previously mentioned. Cronbach’s alpha for the 10-item CES-D scale was 0.79 in the SCD subjects and 0.75 in the non-SCD subjects.

Clinical severity was measured by utilizing two clinical indicators of severity of SCD. First, patients were asked how many sickle cell crisis episodes requiring hospital admissions or emergency room visits occurred within the last 12 months. Second, use of hydroxyurea medication, which is prescribed to decrease the frequency of crisis episodes in patients with the most clinically severe forms of SCD, was included in the measure of severity by asking patients whether or not they were currently being treated with hydroxyurea. Severity of the disease was then classified into the following three groups: low severity = 0 hospital admissions or emergency room visits for sickle cell crisis within the last 12 months and no current use of hydroxyurea; medium severity = one or two hospital admissions or emergency room visits for sickle cell crisis within the last 12 months and no current use of hydroxyurea; high severity = >3 hospital admissions or emergency room visits for sickle cell crisis within the last 12 months or current use of hydroxyurea. Subjects provided information on potential confounding variables, including educational attainment, current occupational status, yearly household income and current marital status, in addition to age and gender on which the SCD and non-SCD subjects were matched. Studies have suggested that women, those that are not married and those that have a poorer socioeconomic status are at risk for elevated depressive symptoms. Educational level, income or occupational status are the most commonly used measures of socioeconomic position. Viagra Professional 100 mg

Statistical Analysis

The Chi-squared test was used to detect sociode-mographic differences between SCD subjects arid non-SCD subjects. Odds ratios for the presence or absence of elevated depressive symptoms were calculated for the three SCD severity groups compared to subjects without SCD using unconditional logistic regression in bivariate and multivariable analyses. Sociodemographic variables that were associated with elevated depressive symptoms in bivariate analysis were included in the multivariable model. Statistical tests were two sided, 95% confidence intervals were reported and p values of <0.05 were considered statistically significant. Statistical analyses were performed using Stata 8 (STATA Corp., College Station, TX) and SPSS 9.0.