Primary Outcomes

Description: Performances on the computerized cognitive test of Multi-Source Interference Task will be examined in terms of speed and accuracy. Participants are instructed to identify the target number, which is different than the other 3 numbers provided on the computer screen. There are two types of trials, congruent and incongruent. Congruent trials have a target number that is always matched its position on the button (e.g., 100, 020, or 223), in contrast, incongruent trials have the target number that is never matched with it position in the button (e.g., 010, 233, or 232). Faster response time and lower error rates indicate better attention.

Description: Participants are instructed to remember the sequence of numbers the data collector told and repeat the numbers right after the instructor finished talking. This test has 2 subsets, Forward-repeat exactly the same sequence, and Backward-repeat the numbers in the backward from last to the first. More digits correctly repeated indicate better attention.

Description: This traditional cognitive test of attention is a paper-pencil based measure and has 2 parts. Part A requires participants to connect a series of randomly arrayed, distinct circles numbered 1 to 25 in correct order as quickly as possible. Part B requires participants to connect a series of 25 circles numbered 1 to 13 randomly intermixed with letters from A to L, alternating between numbers and letters, and proceeding in ascending order (e.g., 1-A-2-B-3 and so on). Faster response time in seconds indicates better attention.

Description: Stroop Test is a color-word test measuring the ability to processe different visual features and ignore distractions. The test has 2 parts of reading letters of color names and colors of color names using 4 color names (i.e., red, blue, yellow, and green). Congruent trials have the same letters and colors of the color names (i.e., red in red color). Incongruent trials have different letters and colors of the color names (i.e., red in blue color). Faster response time and lower error rates indicate better attention.

Description: This self-reported questionnaire has 13 items on 0 to 10 response scales asking effectiveness in behaviors requiring attention. Higher scores indicate better subjective attention

Secondary Outcomes

Description: This self-reported questionnaire consists of 29 items divided into 3 scales measuring self-care maintenance, symptom perception, and self-care management. In addition, self-care confidence is measured by additional 10 items. Each scale is scored separately and standardized to achieve a possible score of 0 to 100. Higher scores indicate better self-care of HF.

Description: Minnesota Living with Heart Failure Questionnaire will be used to measure health-related quality of life. This self-report questionnaire consists of 21 items on which patients are asked to rate how their HF condition impacted their physical and emotional health. Lower scores indicate better HRQL.

Other Outcomes

Description: Venipuncture will be performed to draw the blood by following Indiana University general laboratory safety guidelines. Changes in the serum BDNF levels (ng/ml) and its associations with attention will be examined.

Description: Venupucture will be performed to draw the blood for the possible genetic biomarker. The frequency of BDNF Val66Met genotype (e.g., rs6265) will be examined and attention will be examined by the genotype.

Description: Venupucture will be performed to draw the blood for the possible genetic biomarker. The 3 common allele of APOE (i.e., e2, e3, and e4) will be examined. The frequency of APOE genotypes (e.g., rs7412, rs429358) will be examined and attention will be examined by the genotype.

Description: Venupucture will be performed to draw the blood for the possible genetic biomarker. Specifically, dopamine receptor gene 4 (e.g., 48 bp VNTR) polymorphism and its association with attention will be examined.

Description: Venupucture will be performed to draw the blood for the possible genetic biomarker. The dopamine transporter gene (DAT1) (e.g., rs28363170 - 40 bp VNTR) polymorphism and its association with attention will be examined.