EHR Documentation of Medical Cannabis Use Lags Patient-Reported Measures

Asking primary care patients about the use of cannabis to manage health conditions alongside routine cannabis screening may improve EHR documentation of medical cannabis use, according to a study published in JAMA Network Open.

Researchers supervised a cross-sectional survey in a large health system that conducts routine cannabis screening. The research occurred in Washington state, where medical and nonmedical cannabis use are legal.

Among 108,950 patients who completed routine cannabis screening, the researchers randomly selected 5,000 individuals for a confidential survey about cannabis use using stratified random sampling for frequency of past-year use and patient race and ethnicity.

The survey found that 35.1 percent of patients reported using cannabis for health reasons—predominantly pain, sleep, stress, anxiety, and depression. An additional 26.5 percent of patients reported medical cannabis use in the past year.

The study authors suggested that asking patients about their health reasons for cannabis use may be more informative than asking explicitly about medical use.

“These results suggest that asking patients about their use of cannabis for managing health concerns, such as pain, mood, and sleep, may identify more medical cannabis use than only asking explicitly about medical use,” the researchers noted.

The research also revealed that EHR-documented medical cannabis use prevalence was just 4.8 percent among all primary care patients.

“This study demonstrated that most medical cannabis use is not documented in the medical record—EHR documentation missed 90 percent of patient self-reported cannabis use for health reasons,” the authors wrote.

While future research is needed, the lack of EHR documentation may reflect the absence of health system support for or prioritization of documentation, the researchers suggested. Lack of documentation could also reflect clinician reluctance to discuss medical cannabis use with patients. 

Documentation of health reasons for cannabis use may help providers identify drug interactions, contraindications, and patient-initiated substitution of prescribed medications for cannabis. 

EHR documentation can also support patient-centered conversations about the limited benefits of cannabis use for some health conditions and insufficient evidence for cannabis use for conditions like depression and anxiety.

“Combined with cannabis screening, routinely asking about health reasons for use could improve recognition and documentation of medical cannabis use and the management of health conditions for which cannabis is being used,” the study authors wrote.

This study has several limitations. First, 34 percent of invited patients completed the survey. Although this rate is consistent with nationally declining response rates, the researchers pointed out that it is lower than desired.

Second, a small number of respondents represented a large number of primary care patients who did not use cannabis according to their index screen. However, characteristics of the weighted sample reflect those of the eligible primary care sample, suggesting weights adequately compensated for sampling and survey nonresponse.

Third, the study took place within a health system that routinely screens for the frequency of any past-year cannabis use. While screening does not ask about medical use, it could have led to discussions of patient health reasons for cannabis use. However, this study could not address how often such discussions occurred but were not documented.

Fourth, although the time between the index screen and survey was brief, changes in cannabis use could have happened between the measures.

Additionally, while respondents reflected the demographics of primary care patients in a single health system in one state, the research may not generalize to other primary care populations and settings, especially in states where cannabis use is not legal.