Medical Bulletin 25/ October/ 2024 - Video

Can Aerobic Exercise Help Prevent Chemo Brain Caused by Chemotherapy in Breast Cancer Patients?

Many women who receive chemotherapy experience a decreased ability to remember, concentrate, and/or think—commonly referred to as “chemo-brain” or “brain fog”—both short- and long-term. In a recent clinical trial of women initiating chemotherapy for breast cancer, those who simultaneously started an aerobic exercise program self-reported greater improvements in cognitive function and quality of life compared with those receiving standard care. The findings are published by Wiley online in CANCER, a peer-reviewed journal of the American Cancer Society.

The study trial, included 57 Canadian women in Ottawa and Vancouver who were diagnosed with stage I–III breast cancer and beginning chemotherapy. All women participated in 12–24 weeks of aerobic exercise: 28 started this exercise when initiating chemotherapy and 29 started after chemotherapy completion. Cognitive function assessments were conducted before chemotherapy initiation and after chemotherapy completion.

Women who participated in the aerobic exercise program during chemotherapy self-reported better cognitive functioning and felt their mental abilities improved compared with those who received standard care without exercise. Though neuropsychological testing—a performance-based method used to measure a range of mental functions—revealed similar cognitive performance in the two groups after chemotherapy completion.

Reference: “Aerobic exercise and CogniTIVe functioning in women with breAsT cancEr (ACTIVATE): a randomized controlled trial.” Jennifer Brunet, Sitara Sharma, Kendra Zadravec, Monica Taljaard, Nathalie LeVasseur, Amirrtha Srikanthan, Kelcey A. Bland, Elham Sabri, Barbara Collins, Sherri Hayden, Christine Simmons, Andra M. Smith, and Kristin L. Campbell. CANCER; Published Online: October 21, 2024 (DOI: 10.1002/cncr.35540).

URL Upon Publication: http://doi.wiley.com/10.1002/cncr.35540

Genetically Tailored Diet: Future of Diet Management in IBS Patients?

An international study has found that genetic variations in human carbohydrate-active enzymes may affect how people with irritable bowel syndrome (IBS) respond to a carbohydrate-reduced diet.

The research, which is published in Clinical Gastroenterology & Hepatology, shows that irritable bowel syndrome patients with genetic defects in carbohydrate digestion had a better response to certain dietary interventions. This could lead to tailored treatments for IBS, using genetic markers to predict which patients benefit from specific diets.

Nutrigenetics has highlighted how changes in the DNA can affect the way we process food. Now, this pioneering new study suggests that genetic variations in human carbohydrate-active enzymes (hCAZymes) may similarly affect how irritable bowel syndrome patients respond to a carbohydrate-reduced (low-FODMAP) diet.

The team have now revealed that individuals with hypomorphic (defective) variants in human carbohydrate-active enzymes genes are more likely to benefit from a carbohydrate-reduced diet.

The study, involving 250 IBS patients, compared two treatments: a diet low in fermentable carbohydrates (FODMAPs) and the antispasmodic medication otilonium bromide. Strikingly, of the 196 patients on the diet, those carrying defective human carbohydrate-active enzymes genes showed marked improvement compared to non-carriers, and the effect was particularly pronounced in patients with diarrhea-predominant irritable bowel syndrome (IBS-D), who were six times more likely to respond to the diet. In contrast, this difference was not observed in patients receiving medication, underscoring the specificity of genetic predisposition in dietary treatment efficacy.

Can AI Help Ophthalmologist Diagnose Corneal Infections?

Eye care specialists could see artificial intelligence help in diagnosing infectious keratitis (IK), a leading cause of corneal blindness worldwide, as a new study finds that deep learning models showed similar levels of accuracy in identifying infection. In a meta-analysis study published in eClinicalMedicine, Dr Darren Ting from the University of Birmingham conducted a review with a global team of researchers analysing 35 studies that utilised Deep Learning (DL) models to diagnose infectious keratitis.

AI models in the study matched the diagnostic accuracy of ophthalmologists, exhibiting a sensitivity of 89.2% and specificity of 93.2%, compared to ophthalmologists' 82.2% sensitivity and 89.6% specificity. The models in the study had analysed over 136,000 corneal images combined, and the authors say that the results further demonstrate the potential use of artificial intelligence in clinical settings.

The AI models also proved effective at differentiating between healthy eyes, infected corneas, and the various underlying causes of infectious keratitis, such as bacterial or fungal infections. While these results highlight the potential of Deep Learning in healthcare, the study's authors emphasised the need for more diverse data and further external validation to increase the reliability of these models for clinical use.

Reference: Diagnostic performance of deep learning for infectious keratitis: a systematic review and meta-analysis Ong, Zun Zheng et al. eClinicalMedicine, Volume 77, 102887

Long Term Arsenic Exposure May Be Risk Factor for Cardiovascular Disease

Long term exposure to arsenic in water may increase cardiovascular disease and especially heart disease risk even at exposure levels below the federal regulatory limit (10µg/L) according to a new study at Columbia University Mailman School of Public Health. This is the first study to describe exposure-response relationships at concentrations below the current regulatory limit and substantiates that prolonged exposure to arsenic in water contributes to the development of ischemic heart disease.

The researchers compared various time windows of exposure, finding that the previous decade of water arsenic exposure up to the time of a cardiovascular disease event contributed the greatest risk. The findings are published in the journal Environmental Health Perspectives.

To evaluate the relationship between long-term arsenic exposure from CWS and cardiovascular disease, the researchers used statewide healthcare administrative and mortality records collected for the California Teachers Study cohort from enrollment through follow-up (1995-2018), identifying fatal and nonfatal cases of ischemic heart disease and cardiovascular disease. Working closely with collaborators at the California Office of Environmental Health Hazard Assessment (OEHHA), the team gathered water arsenic data from CWS for three decades (1990-2020).

The analysis included 98,250 participants, 6,119 ischemic heart disease cases and 9,936 Cardiovascular disease cases. Leveraging the extensive years of arsenic data available, the team compared time windows of relatively short-term (3-years) to long-term (10-years to cumulative) average arsenic exposure. The study found decade-long arsenic exposure up to the time of a cardiovascular disease event was associated with the greatest risk, finding peak mortality of acute myocardial infarction around a decade after a period of very high arsenic exposure. This provides new insights into relevant exposure windows that are critical to the development of ischemic heart disease.

Those exposed to 1 to <5 µg/L had modestly higher risk of ischemic heart disease, with increases of 5 to 6 percent. Risk jumped to 20 percent among those in the exposure ranges of 5 to <10 µg/L, and more than doubled to 42 percent for those exposed to levels at and above the current EPA limit ≥10µg/L. The relationship was consistently stronger for ischemic heart disease compared to cardiovascular disease, and no evidence of risk for stroke was found, largely consistent with previous research and the conclusions of the current EPA risk assessment.

Reference: Long-term exposure to arsenic in community water supplies and risk of cardiovascular disease among women in the California Teachers Study, Environmental Health Perspectives (2024).