Ann Robinson’s research reviews—11 June 2021

Ann Robinson reviews the latest research from the top medical journals

Tackling the itch

Two large phase III trials—Measure Up 1 and Measure Up 2—have found that upadacitinib, an oral Janus kinase inhibitor, has potential as a safe and effective treatment option for adults and adolescents with moderate to severe atopic dermatitis. This drug blocks multiple cytokine signalling pathways involved in itching and is already licensed for use in inflammatory arthritis in the US and Europe. By week 16, a higher proportion of patients had 90-100% improvement in symptoms (skin signs, itch, pain, and quality of life) after 15 mg and 30 mg of upadacitinib compared with placebo. The safety profile was good, although acne was a reported side effect (>5%), which will be an unwelcome trade-off for people with eczema.

Lancet doi:10.1016/S0140-6736(21)00588-2

Hope for women with high risk breast cancer and BRCA mutation

This important trial showed that one year treatment with olaparib (a poly ADP ribose polymerase (PARP) inhibitor that stops cancer cells repairing) in addition to standard care reduced risk of recurrence and progression to metastatic disease in patients with high risk early breast cancer and BRCA1 or BRCA2 mutations compared with placebo: percentage free of invasive disease at three years was 85.8% versus 77.1%. Serious adverse events were similar with olaparib or placebo (8.7% v 8.4%), but longer term follow-up than the median 2.5 years observed to date is important, especially to look out for pneumonitis and new cancers. The results imply that all women with early breast cancer could be tested for their BRCA status to guide choices in systemic treatments such as olaparib. Further work is needed to assess whether olaparib has a role as adjuvant therapy in other hereditary (non BRCA) forms of breast cancer and in women with lower risk clinical features than the ones in this trial.

N Engl J Med doi:10.1056/NEJMoa2105215

Widening income-based disparities in respiratory health in the US

A large repeated cross-sectional analysis of US health surveys (1959-2018) has found that socioeconomic variation in respiratory symptoms, disease prevalence, and lung function have mostly stayed the same or even worsened over the past 60 years. Air quality has improved and cigarette smoking has fallen, but the gains have not been equally distributed. Asthma prevalence rose for all children after 1980, but more sharply among poorer children, and the difference in diagnosed adult chronic obstructive pulmonary disease between the highest and lowest income quintiles was 4.5% in 1971 and 11.3% in 2013-18. The reasons for these disparities may include unhealthy workplaces, living in polluted areas, and unequal access to healthcare. The surveys rely on self reported symptoms, diagnoses, and socioeconomic data, and any linkage between income and illness risks the charge of reverse causality (in which being ill makes you poor rather than vice versa). That seems unlikely given the widening income-based disparities over time.

JAMA Intern Med doi:10.1001/jamainternmed.2021.2441

Continuous glucose monitoring; associated with better control of diabetes

Adults with poorly controlled type 2 diabetes (mean HbA1c level 9.1%) who were taking basal insulin (and no short acting prandial doses), improved their control when they used continuous glucose monitoring (CGM) for eight months compared with standard blood glucose meter monitoring (fall in HbA1c -1.1% v -0.6%), according to this small randomised trial. Longer follow-up is needed to see whether the benefits of CGM are maintained, and, although it was popular with users, a third of CGM users still had HbA1c >8%. Measurement is no substitute for more effective treatment.

JAMA doi:10.1001/jama.2021.7444

Clinical benefits associated with real-time continuous glucose monitoring

A second study asks whether continuous glucose monitoring (CGM) translates into clinical benefits. A large retrospective cohort, mostly of people with type 2 diabetics taking insulin, found that use of real-time CGM was associated with lower HbA1c levels compared with non-users (difference -0.4%) and fewer episodes of severe hypoglycaemia, but no difference in visits to emergency department or hospitalisations for other causes including hyperglycaemia. There are numerous caveats, including a risk of selection bias inherent in this type of study design.

These two studies add to a compelling narrative in favour of CGM. As an editorial says: “The time has come to broaden access to CGM” in type 2 diabetes.

JAMA doi:10.1001/jama.2021.6530

Ann Robinson is an NHS GP and health writer and broadcaster