UCLA Health Tip Sheet Feb. 21, 2023
Below is a brief roundup of news and story ideas from the experts at UCLA Health. For more information on these stories or for help on other stories, please contact us at uclahealthnews@mednet.ucla.edu.
Body composition, not BMI, may signal risk for cardiovascular disease Body mass index has long been a measure of a person’s risk of developing cardiovascular disease, but body composition and its role in the disease have not been well studied. In a new study, UCLA researchers predicted higher fat mass would be linked to higher levels of coronary artery calcification (CAC) -- a marker of subclinical cardiovascular disease – and higher fat-free mass would be linked to lower levels of CAC. Using computed tomography scans and bioelectrical impedance analysis to study CAC and body composition in 3,129 non‐Hispanic Whites, Blacks, Hispanics, and Chinese patients, the researchers unexpectedly found that higher fat-free mass and, to a lesser extent, higher fat mass were linked to high levels of CAC. The researchers cautioned that bioelectrical impedance analysis could not identify the quality of fat or fat-free mass. Given these findings, the researchers say measuring body composition rather than using BMI to assess obesity may be a better approach to evaluating cardiovascular disease risk. Read the study published Feb. 8, 2023 in the Journal of the American Heart Association.
Bariatric surgery reduces risks of hospitalization for heart failure Bariatric surgery has been found to reverse the ill effects of diabetes and may be protective against obesity-related cancers. Because obesity rates are on the rise across the globe, UCLA researchers set out to study other health benefits weight loss surgeries confer, in particular the link between the procedures and acute heart failure hospitalizations. After analyzing data from the Nationwide Readmissions Database from 2016 to 2019, the researchers found bariatric surgery was associated with lower odds of being hospitalized with acute heart failure. Among patients hospitalized with acute heart failure, prior bariatric surgery was associated with lower risks of death, prolonged ventilation, and acute renal failure. Beyond the health benefits, those who had undergone surgery stayed one fewer day in the hospital and incurred about $1,200 less in hospital costs compared to age matched cohorts. Read the study in Surgery for Obesity and Related Diseases.
Pesticides may also worsen Parkinson’s symptoms: While researchers have consistently found an association between pesticide exposure and higher risk of developing Parkinson’s disease, there has been little study of whether such exposure can accelerate the course of the disease. In a new study of 53 pesticides associated with Parkinson’s onset, researchers led by UCLA assistant professor of neurology Kimberly Paul, PhD, identified 10 pesticides that are associated with faster progression of motor and non-motor symptoms. Furthermore, exposure to six of those pesticides was associated with worsening of multiple endpoints researchers measured. Two pesticides, copper sulfate (pentahydrate) and MCPA (dimethylamine salt), were associated with all three endpoints measured: motor function, cognitive function, and depressive symptoms. Read the study in the journal Science of the Total Environment.
Repurposing an old drug for a rare disease: A drug used to treat epilepsy, retigabine, may help manage episodic attacks of paralysis in patients with the rare inherited muscle disease Hypokalemic Periodic Paralysis (HypoPP), according to a new study that tested retigabine in genetically engineered mice. There’s a strong need to identify new HypoPP treatments since existing ones only improve symptoms in about half of patients and have considerable side effects. HypoPP is often marked by reduced potassium levels in the blood during episodes of muscle weakness. While it was known that retigabine affects a potassium channel that plays an important role in the heart and brain, the channel wasn’t previously known to exist in skeletal muscle. However, the new study led by Dr. Stephen C. Cannon, chair of the physiology department at the UCLA David Geffen School of Medicine, found that retigabine helps stabilize the membrane potential of skeletal muscle, thereby protecting against attacks of muscle weakness. Read the study, published online Jan. 30, in the journal Brain.
Women treated with thrombectomy for pulmonary embolism fare worse A new study led by UCLA researchers analyzed the different outcomes in men and women with a pulmonary embolism who are treated by a percutaneous pulmonary artery thrombectomy- a procedure in which a catheter is placed in a patient’s lung to dissolve or remove a blood clot. After analysis of a national cohort of US patients from an inpatient claims-based database, researchers reported that women had higher rates of procedural bleeding, vascular complications, and needed more blood transfusions compared to men. They also found that women had higher in-hospital death rates and were more likely to go a nursing home or an assisted living facility instead of returning home after discharge. Given these disparities in outcomes, study authors are calling for more sex-based research. Read the study in the January 1, 2023 issue of CHEST.
A new clue about Parkinson’s progression The transmission of misfolded proteins in the brain is a key mechanism for the progression of various neurodegenerative diseases including Parkinson's disease and Alzheimer's disease. Chao Peng, PhD, an assistant professor of neurology, found a novel mechanism that regulates the transmission of one of these pathological proteins, misfolded alpha-synuclein, which leads to disease progression in Parkinson’s. This mechanism is the discovery that many modifications that a cell makes in these proteins alter their ability for transmission in the brain and disease progression. This discovery not only provides critical insights into disease mechanism but also facilitates the development of novel therapy for neurodegenerative diseases. Read the study, published Jan. 23, in Nature Neuroscience.
Urban heat islands, redlining and kidney stones The persistent rise in kidney stone prevalence in recent decades has prompted much speculation as to the causes. There has been some discussion about the effect of heat on nephrolithiasis. A review of recent data suggests that heat may play a role in stone formation on a large scale and among African-Americans in particular. A new UCLA-led study led by Dr. Kymora B. Scotland states that African-Americans are the race/ancestry group with faster rates of increasing incidence and prevalence of kidney stones. Researchers also found that urban heat islands in the United States have resulted in part from the effects of redlining, a practice of systematic segregation and racism in housing that led to the development of neighborhoods with substantial disparities in environmental conditions. Dr. Scotland and her team hypothesize that the increased temperatures experienced by residents in redlined communities, many of whom are African American may contribute to the 150% increase in the prevalence of kidney stones in African Americans in recent decades. Read the study in the January 1, 2023 issue of Current Opinion in Nephrology and Hypertension.
Gender-affirming hormones tied to mental health for transgender youth Transgender and nonbinary teens who receive gender-affirming hormones experience improvement in body satisfaction, life satisfaction and less depression and anxiety than before treatment. These findings are according to newly-published research by a four-site prospective, observational study and co-authored by Marco A. Hidalgo, PhD. Dr. Hidalgo is a clinical psychologist and Associate Clinical Professor of Medicine at the David Geffen School of Medicine at UCLA. Read the study published January 19, 2023 in the New England Journal of Medicine.