JMIR Publications

ABSTRACT

Background:

Patients with colorectal cancer (CRC) often present with multiple comorbidities, with many that can affect treatment and survival; however, the majority of studies completed to date have often relied on self-reported conditions and limited to a few common diseases. Thus, a simultaneous assessment of the entire spectrum of chronic disease co-occurrence in CRC patients at diagnosis, especially in developing regions, has not yet been performed.

Objective:

To provide a multidimensional approach to understand the full spectrum of chronic disease and diseases co-occurrence among newly diagnosed CRC patients in southwestern China, to investigate the comorbidity patterns and access their age, sex, region, and cancer site differences.

Methods:

In this retrospective observational study, a provincial hospital discharge dataset of 678 hospitals from 2015 to 2020 was used to identify new CRC cases in 2020 and their history diseases. We examined all chronic diagnoses using the ICD-10 codes at three digits and focused on chronic diseases with > 1% prevalence in at least one subgroup (one-side test, P <.025), which resulted in a total of 66 chronic diseases. Phenotypic comorbidity networks were constructed across all CRC patients and different subgroups by sex, age group (18-59, 60-69, 70-79, 80+), area (urban/rural), and cancer site (colon/rectal), with comorbidity as a node and linkages representing significant correlations between multiple comorbidities.

Results:

About 29,610 CRC new cases occurred in Sichuan, China in 2020, with mean age at diagnosis of 65.6 ± 12.9 years and 75.5% having at least one comorbidity. The most prevalent comorbidities were hypertension (29.0%, 95% CI: 28.5%, 29.5%), hyperplasia of prostate (21.9%, 95% CI: 21.3%, 22.5%), and chronic obstructive pulmonary disease (COPD: 14.2%, 95% CI: 13.8%, 14.6%). Prevalence of single comorbidities was different in each subgroup in most cases. Comorbidities were closely associated, with disorders of lipoprotein metabolism and hyperplasia of prostate mediating correlations between other comorbidities. Males and females shared 58.3% of disease pairs, whereas the male–female disparities occurred primarily in disease coexisting with COPD, cerebrovascular diseases, atherosclerosis, heart failure, or renal failure in males and with osteoporosis or gonarthrosis in females. Urban patients generally had more comorbidities with higher prevalence and more complex disease coexistence relationships, whereas rural patients were more likely to have co-existing severe diseases, such as heart failure comorbid with sequelae of cerebrovascular disease or COPD.

Conclusions:

Male–female and urban–rural disparities in prevalence of single comorbidities and their complex coexistence relationships in CRC new cases were not due to simple coincidence. The results reflect clinical praxis in CRC patients and emphasize the importance of measuring comorbidity patterns in terms of individual and coexisting diseases in order to better understand comorbidity patterns.