Sex differences in the prevalence of individual chronic conditions in a cardiac rehabilitation population

The United States Department of Health and Human Services has defined 21 chronic conditions lasting one year or greater and which require ongoing medical treatment. The presence of multiple chronic conditions (multimorbidity) is closely linked to greater physical disability, increased health care utilization, reduced quality of life, and higher mortality rates. In the general population, studies have shown the prevalence of multimorbidity to be greater in females compared to males. Recently, data has suggested that patients enrolled in cardiac rehabilitation (CR) have a significantly greater number of chronic conditions compared to the general population. Whether these same sex differences in the prevalence of individual chronic conditions are present in the CR population has not been examined.

The purpose of this study is to determine whether differences exist in the prevalence of individual chronic conditions between male and female CR patients. We hypothesize that female CR patients will demonstrate greater prevalence of individual chronic conditions compared to men.

Using the local Epidemiology Project records-linkage system, we identified patients who attended (≥1) CR sessions from 1995-2019. The prevalence of 21 chronic conditions was extracted from the patients’ medical records at the time of enrollment in CR (Table 1). We conducted chi-squared analysis to identify differences in the prevalence of each individual chronic condition between the sexes. Statistical significance was defined by p≤0.05.

Of the 13,056 CR patients identified (age: 65.7±12.8 yrs old), 4,107 (31.5%) were female. Male CR patients were significantly younger compared to female counterparts (64.8±12.1 yrs old vs. 67.6±13.6 yrs old; p≤0.001). Females demonstrated a greater number of total chronic conditions compared to males (median (IQR): 7.0 (5.0, 9.0) vs 6.0 (5.0, 8.0); p≤0.001). Females demonstrated a greater prevalence of the following 12 individual chronic conditions compared to males: HTN, CHF, ARR, STR, ART, CAN, CPD, HEP, OST, ANX, DEM, and DEP (p≤0.05, for all). There was a trend for greater prevalence of ARR in females compared to males (p=0.07). In contrast, males experienced a greater prevalence of the following four chronic conditions compared to females: CAD, LIP, AST, and SUB (p≤0.001, for all). There were no differences between sexes for CKD (p=0.87), SZO (p=0.70), or AUT (p=0.31).

Our data suggest the trend for greater prevalence of chronic conditions in females in the general population is consistent within the CR population. Specifically, 12 of 21 (57%) individual chronic conditions were significantly more prevalent in female CR patients whereas only 4 (19%) conditions were more prevalent in males. These data emphasize the need to better understand the relationship between sex and risk for individual chronic conditions, particularly in patients enrolled in CR.