Osteoporosis in colorectal cancer survivors: analysis of the linkage between SWOG trial enrollees and Medicare claims

To explore the rates of osteoporosis (diagnosis and screening) and fractures in colorectal cancer survivors (CRCS), records of clinical trial enrollees was linked to Medicare. Female/male risk of fracture in CRCS is 74% higher than general population. Less than 30% of male and female CRCS receive osteoporosis screening. Osteoporosis is a significant morbidity in CRCS.IntroductionIn the USA, the population of colorectal cancer survivors (CRCS) is on the rise. Calcium and vitamin D are the common thread between colorectal cancer and osteoporosis. We set to explore the patterns and prevalence of osteoporosis (OP) and osteoporotic fractures (OF) in CRCS who received fluorouracil-based therapy on SWOG trials.MethodsData for CRCS from three SWOG phase III treatment trials between 1994 and 2000 (N=3775) were linked to Medicare claims (N=1233). OP was identified using ICD9 and HCPCS codes; OF was defined using a more restricted set of codes. We compared patterns of OP, OF, and screening for OP by gender in CRCS. Given the gender disparities in the rates of OP and OF, we used data from the National Health Interview Survey (NHIS) and the National Hospital Discharge Survey (NHDS) to assess the ratio of OF in females and males in general population.ResultsForty-seven percent of females and 15% of men CRCS had OP claims. Female CRCS were more likely than males to have OP (HR=4.76 [3.77-6.01], p<0.0001) and OF (HR=2.64 [2.04-3.42], p<0.0001). In the general population, the female to male ratio of OF was 1.67 as opposed to 2.90 in CRCS, indicating a significantly larger gender disparity of OF in CRCS (p<0.001). Only 7% of men and 27% of women CRCS had OP screening.ConclusionDespite a low rate of OP screening, the gender disparity of OF in CRCS is more pronounced than the general population. These findings provide an impetus for studying OP and OF in CRCS.