Participation in Physical Activity and Risk for Amyotrophic Lateral Sclerosis Mortality Among Postmenopausal Women

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative fatal disease that attacks neurons in the brain and spinal cord. It is also known as Lou Gehrig’s disease, after the famous baseball player was diagnosed. ALS disables the voluntary control of muscles and weakens functional movements requiring muscle. This is a major concern because there are no known causes for this disease. However, studies are being done to correlate risk factors associated it.

A study conducted examined a potential association between exercise and risk of ALS for postmenopausal women. 161,809 postmenopausal women were recruited to participate in the study ranging from age 50 to 79. The women were frequently evaluated with a self-administered questionnaire to determine the intensity level and extent of exercise performed in their life. Over the course of the study 165 of the 161,809 women died of ALS. The median age of these women was 66 years.

The results showed that the mortality rates of women with no physical activity at 7.4 per 100,000 person years and that increased to 10.6 per 100,000 for women engaged in strenuous exercise 3 days a week. The ALS death odds ratio for women that exercise frequently to women who didn’t was 1.56. Women with a BMI of 30.0 or greater had the lowest incidence of ALS and there was a possible pathophysiological connection between physical activity and ALS by abnormal mitochondrial activity from greater oxidative stress. They state that despite these findings, strenuous exercise provides overall benefit to general well being, total mortality, and cardiovascular health.

I think this study highlights the challenges researchers and health care providers face with ALS. There isn’t a cure nor treatment but progress is being made in understanding this disease. Genetic predispositions and environmental factors may play a significant role in the development. In the future, we should expect to see more studies on risk factors beyond physical activity and clinical trials with patients having ALS utilizing gene and drug therapies.

Eaglehouse YL, Talbott EO, Chang Y, et al. Participation in Physical Activity and Risk for Amyotrophic Lateral Sclerosis Mortality Among Postmenopausal Women. JAMA Neurol. doi:10.1001/jamaneurol.2015.4487 (published 19 January 2016).

Association of Fitness in Young Adulthood With Survival and Cardiovascular Risk

Evidence has shown the benefits of exercise to be prognostic factor for overall health and developmental changes to cardiovascular system for adults. Specifically, cardiorespiratory fitness (CRF) is one predictive indicator for older adults with cardiovascular disease but a study was conducted to examine the risk factor of CRF of young adults linked to cardiovascular disease (CVD). Patients underwent a treadmill exercise test at the beginning of the study and repeated the test 7 years later. They assessed obesity, left ventricular mass and strain, coronary artery calcification, and vital status, and incident CVD at different time points to grasp the progression of their cardiovascular health.

The results showed that individuals with longer exercise duration had lower risks of mortality (15%) and cardiovascular disease (12%). There was an association between cardiorespiratory fitness and myocardial phenotypes. Those with a higher CRF levels had a lower left ventricular mass index and a better global longitudinal strain. They did not find a correlation between fitness level and coronary artery calcification. This shows early detection of cardiovascular disease through cardiorespiratory fitness as a biomarker can be beneficial in young adults and can be an influential factor in changing the fitness lifestyle.

I believe this assessment reminds us that preventative measures can be taken at an early stage in adulthood that will lead to better health outcomes. Genetics will be anticipated but there are manageable variables that people can control. In the future, we could see applications of CRF to other health complications, such as diabetes and obesity.

Question: Could the cardiorespiratory fitness of teenagers prior to adulthood be an indicator for potential cardiovascular diseases later in life?

 

JAMA Intern Med. 2016;176(1):87-95.

Interactive effects of physical fitness and body mass index on the risk of hypertension

A cohort study with Sweden was conducted over a long duration of time. They measured the aerobic capacity, muscular strength, and body mass index during military consignment evaluations in Sweden from 1969 to 1997. This accounts for 97% of 18 year old men in Sweden during that duration of time. The researchers performed follow-up evaluations of these patients in 2012 to measure their degree of hypertension. The study measures the correlation between aerobic capacity, muscular strength, and body mass index in late adolescence and the degree of hypertension in adulthood. The results showed that high body mass index and low aerobic capacity combined posed the highest risk of developing hypertension later in life. In patients with normal body mass index, a low aerobic capacity still posed a significant risk of developing hypertension. All statistics were adjusted for socioeconomic status and family history.

JAMA Intern Med. 2016;176(2):210-216.
I think this research is important because it shows that patients can intervene at a young age to prevent disease states like hypertension later in life. It demonstrates that diseases, even ones that seem to be hereditary like hypertension, are not always inevitable. We can take action now to lower our risk.
I think further research should be done to measure how aerobic capacity, muscular strength, and body mass index affect risk of developing hypertension in women, as well as other ethnicities.