Impact of Multiple Chronic Diseases and Risk Factors on Health-Related Quality of Life Among Adults, Texas, 2011

BACKGROUND:  Almost two-third of the adult population in Texas has at least one chronic condition/risk factor that compromises quality of life. Improving quality of life is recognized as one of the foundation health measures by Healthy People 2020. The Centers for Disease Control and Prevention (CDC) developed a measure calculating the number of unhealthy days to assess health-related quality of life (HRQoL). This study aims to explore the impact of chronic diseases/risk factors on HRQoL and measure the number of unhealthy days associated with multiple chronic diseases/risk factors.

METHODS:  Data from 2011 Texas Behavioral Risk Factor Surveillance System’s survey were analyzed. The survey included questions related to HRQoL. The summary index of unhealthy days was calculated using CDC’s method by combining the number of physical and mental unhealthy days with a logical maximum of 30 unhealthy days. The survey included questions on doctor-diagnosed chronic diseases: cardiovascular diseases, cancer, arthritis, depression, respiratory diseases, diabetes and kidney disease and risk factors: obesity, high blood pressure, high blood cholesterol and disability. A categorical variable (0, 1-2, 3+ chronic diseases/risk factors) for the total number of chronic diseases was created using a total of 11 chronic diseases/conditions and risk factors listed. The age-adjusted mean number of unhealthy days per month was calculated using linear regression analysis using SAS 9.2.

RESULTS:  Approximately 40% of adults with three or more chronic diseases reported having fair or poor general health while 6% of the adults without any chronic diseases reported the same (Chi-square P-value: <0.0001). Adults with three or more chronic diseases reported more than four times the mean number of physically (8.3 days) and mentally (6.0 days) unhealthy days in past 30 days than adults without any chronic conditions who reported 1.4 physically and 2.0 mentally unhealthy days. Average total number of unhealthy days suggested that adults with three or more chronic diseases experience approximately two weeks each month (12.7 days) in an unhealthy state compared to only 2.9 days for adults with no chronic conditions (P-value:<0.0001).

CONCLUSIONS:  The presence of multiple chronic conditions is associated with poorer HRQoL and has a major impact on time spent in an unhealthy state.  Major losses of productivity at the population level may be related to the amount of time spent in an unhealthy state. Public health strategies should be used to improve disease self-management for individuals with multiple conditions and risk factors that are linked to chronic conditions.