packs, consisting of 1 reader and 2 14-day sensors, and the impact of continued use on glycemic control. More than half (21/40) continued to use the system beyond the trial period. The mean A1C of patients who continued using FGM decreased by 1.14% at 3 months, compared to an increase of 0.17% in those who did not (p¼0.038). Despite small sample size, there was also a trend of decreased basal and bolus insulin requirements in patients continuing use. These results show benefit and support the implementation of public coverage because greater adherence of self-monitoring of blood glucose results in improved glycemic control which, ultimately, reduces the risk of long-term diabetes associated complications and health-care costs. 135 Diabetes Overtreatment and Averse Outcomes Among Older Adults With Diabetes: A Population-Based Study ILIANA C. LEGA, MICHAEL CAMPITELLI, PETER C. AUSTIN, YINGBO NA, SUSAN E. BRONSKILL, FREDA LEUNG, AFSHAN ZAHEDI, CATHERINE YU, PAULA A. ROCHON, LORRAINE L. LIPSCOMBE Toronto, ON Background: Older adults with diabetes may be particularly vulnerable to the effects of overtreatment, defined as intensive glycemic control whereby harms likely exceed benefits. We esti- mated the prevalence of diabetes overtreatment in older adults and its impact on adverse outcomes. Methods: We conducted a retrospective population-based cohort study using Ontario administrative databases of adults >75 years old with prevalent diabetes, treated with anti-hyperglycemic therapy from 2014 to 2015. Based on the first HbA1C in our study period, we identified individuals with overtreatment, defined as HbA1C <¼7% and baseline use of insulin/sulphonylurea, and used a regression model to evaluate the association between over- treatment and 30-day risk of emergency room (ED) visits, hospi- talizations or death after adjustment for inverse probability of treatment weighting propensity score. Results: Of the 108,620 older adults with diabetes, 66,341 had an HbA1C <¼7% and overtreatment was identified in 23,484 (21.6%); 42,253 (38.9%) had an HbA1C between 7.0 and 8.5%, of which 16,488 (15.1%) were not prescribed insulin/sulphonylurea. Over- treatment was associated with a significant increase in ED visits, hospitalizations or death compared to having an HbA1C 7-8.5% not prescribed insulin/sulphonylurea (adjusted relative risk, aRR 1.98, 95% confidence interval, CI 1.45-2.72). Conclusion: More than 1 in 5 Ontario adults with diabetes aged 75 years or older have evidence of potential overtreatment. Compared to patients with higher HbA1C, overtreatment was associated with a 2-fold increase in risk of serious adverse outcomes. Our findings underscore the need to re-evaluate gly- cemic targets and reconsider use of medications that promote hypoglycemia in older adults. 136 Systematic Content Evaluation of Canadian Diabetes Mobile Apps MARY ELIZABETH NGUYEN, NAFIS HOSSAIN, ROHIN TANGRI, JAY SHAH, FIONA THOMPSON-HUTCHISON, PAYAL AGARWAL, ILANA J. HALPERIN London, ON Background: People living with diabetes mellitus are increasingly using mobile apps to assist in self-management through blood glucose (BG) tracking. However, identifying safe and appropriate mobile applications is difficult for both patients and health-care providers (HCPs). Objectives: 1) Review diabetes apps available in Canada using the Mobile App Rating Scale (MARS) tool and generate usability scores for each; 2) Characterize availability of features across all apps; 3) Evaluate clinical safety of bolus insulin calculators; and 4) Evaluate quality of exportable BG reports meant for HCP use. Methods: Two primary reviewers searched for, screened and evaluated diabetes apps from android and iOS apps stores resulting from the search terms “glucose” and “diabetes.” Sev- enty-five apps were scored. Apps were reviewed based on a predefined quality checklist, including availability of features and the MARS tool. Results: Overall, MARS quality rating score was 3.57/5. The functionality subsection scored the highest (3.93/5) and engage- ment scored the lowest (3.04/5). The majority of apps have the ability to track carbohydrate intake (54/75), send reminders (46/ 75) and can generate BG reports (52/75), but few have bolus insulin calculators (8/75) and remote diabetes support (10/75). Of the 52 that generate BG reports, most lacked key features, such as range and average BG by time of day, highlighting hypoglycemia, or providing statistics in keeping with the ambulatory glucose profile recommendations. Conclusion: Despite widespread availability of many iOS and Android diabetes management apps, few are of high quality. 137 Quality of Diabetes Care Among Cancer Survivors XINYUN LIANG, JACOB ETCHES, BOGDAN PINZARU, KAREN TU, LIISA JAAKKIMAINEN, LORRAINE L. LIPSCOMBE Toronto, ON Background: As cancer survivorship continues to improve, management of comorbid diabetes has become an increasingly important determinant of health outcomes for cancer patients. This study aimed to compare indicators of diabetes quality of care between diabetes patients with and without a history of cancer. Methods: We used the [name of database] database, a database of [province] primary care EMR charts linked to administrative data, to identify patients with diabetes and at least 1 year follow up. Persons with a history of cancer were matched 1:2 on age, sex, and diabetes duration to those without cancer. We compared recom- mended diabetes quality of care indicators between persons with and without cancer using a matched cohort analysis. Results: Among 229,627 patients with diabetes, we identified 2,275 cancer patients and 4,550 controls; 86.5% had diabetes diagnosed after cancer. Compared to controls, cancer patients were significantly less likely to receive ACE inhibitors or ARBs (OR 0.75 [95% CI 0.64-0.89]), receive statin therapy if age 50-80 years (OR 0.79 [95% CI 0.68-0.92]) and achieve an LDL cholesterol level <2.0mmol/L (OR 0.82 [95% CI 0.74- 0.91]). There were no differences in recommended clinical testing or achieving A1C and blood pressure targets between groups. Conclusion: Cancer survivors with diabetes are less likely to receive recommended cardiovascular risk-reducing therapies compared to non-cancer patients of similar age, sex and diabetes duration. Further studies are warranted to determine if these associations are linked to worse survival, cardiovascular outcomes and quality of life. Abstracts / Can J Diabetes 43 (2019) S19eS46 S46