Pharmacists Play a Crucial Role in Blood Sugar Management

By Irene Yeh

Hyperglycemia, also known as high blood sugar, is commonly overlooked in cancer patients. Not only do 20% of cancer patients have diabetes, but cancer therapies—such as chemotherapy, immunotherapy, and corticosteroids—can also raise blood sugar levels, which can lead to diabetes. Poorly controlled glucose levels can also increase the risk of infection and reduce the effectiveness of cancer treatment. Despite these risks, there have been few studies done on how to manage blood sugar levels for cancer patients.

Researchers from the University of California, San Diego, set out to determine how to bridge this gap. In their study, published in Diabetes Spectrum (DOI: 10.2337/ds25-0059), they evaluated the lack of glycemic outcomes of cancer patients referred to the UC San Diego Health Diabetes and Medication Education Clinic (DMEC) from 2019-2024.

Extracting Data from the DMEC

DMEC is run by two clinical pharmacists who specialize in helping patients manage diabetes. Patients are referred from various specialties—oncology, family medicine, endocrinology, and more—and the pharmacists conduct one-on-one visits to educate the patients about managing diabetes or hyperglycemia, adjusting medications, and improving lifestyle habits. Each year, DMEC sees 600-700 patients and has telehealth services available.

Patients with cancer are given a complimentary CGM sensor during the initial visit to provide better glycemic readings. Since hemoglobin A1c (HbA1c) levels could be unreliable in patients with anemia, the sensor offers a clearer picture of glycemic trends. If patients already use a CGM, then the pharmacists review the past two weeks of data to guide treatment. Patients who are using insulin may receive prescriptions for continued CGM use. If a CGM is not used, then regular finger-stick readings are used instead.

The study analyzed 79 adult oncology patients with hyperglycemia. The average age was approximately 63 years old, with 57% of the participants being female, 44.3% of mixed-race descent, and 57.7% of non-Hispanic descent. The most common type of cancer was solid tumors at 63.3%, with about one-third of the participants having breast cancer. The baseline HbA1c was 8.1; 68.4% of patients received non-insulin antiglycemic medications, and 40.5% used insulin prior to their first DMEC visit. Almost 76% of the cohort had a telehealth encounter as either initial or follow up visit, and the average number of scheduled visits with a DMEC pharmacist was about two visits.

The study reviewed charts from adults with Type 2 diabetes, newly diagnosed diabetes, or treatment-related hyperglycemia who also had cancer. The team checked for changes in hBA1c levels after three, six, and nine months, as well as CGM data. The analysis compared outcomes for people using CGM sensors and those who did not.

The Expanding Role of the Pharmacist

The results revealed that cancer patients with diabetes experience significant improvements in HbA1c levels. There was a .99% improvement from baseline at three months, a .88% improvement at six months, and a 1.19% improvement at nine months. CGM metrics also improved: 38 patients who used CGMs also showed improvements, with a 20.9% increase in time in range (TIR) from two weeks to 12 weeks. There was also a .76% decrease in glucose management indicator at 12 weeks.

However, the study also has several limitations. For one, there is no control group, and the sample size is quite small. The data on patients who used steroids also did not include those who started steroids after the first DEMC visit nor patients who received steroid injections as part of their cancer treatment, which can limit the findings after the analysis.

Furthermore, CGM data accuracy relies on wearing the device at least 70% of the time over a two-week period. During the fourth and twelfth week, fewer patients had evaluable CGM data, which means the reliability of the glycemic trends is limited. Additionally, emergency visits, infections, hospitalizations, cancer treatment delays, cancer recurrence, and other outcomes were not assessed. However, the observed improvements are notable and highlight the need for clinical pharmacists to have a bigger role in helping cancer patients manage their diabetes or hyperglycemia. While further studies need to be conducted to fully confirm these findings and assess additional outcomes, the DMEC is a promising example of expanding pharmacists’ roles in helping cancer patients.