Glucose intolerance during pregnancy may put women at greater risk for heart disease. According to Baiju Shah, MD, PhD, FRCP, of the Institute for Clinical and Evaluative Sciences in Toronto, co-author of a recent study on women with gestational diabetes, even mild glucose intolerance—below the threshold for gestational diabetes—increases the chances of later cardiovascular disease. 
Gestational diabetes had been connected to cardiovascular disease prior to this study, but little was known of the links between minor glucose intolerance and heart disease. Type 2 diabetes and cardiovascular disease share several characteristics including obesity, insulin resistance and cholesterol problems. Oftentimes, individuals with one condition will develop the other. Women with gestational diabetes may experience similar metabolic complications as soon as 3 months after giving birth.

Researchers analyzed the medical records of all Ontario women between the ages of 20 and 49 who had given birth between April 1994 and March 1998.  Participants were divided into three groups: those who were diagnosed with gestational diabetes, those who received an oral glucose tolerance test, and those who were not screened using oral glucose testing. One birth was selected at random for women with multiple deliveries; the median ages were between 29.2 and 31.1.

Women are tested for gestational diabetes (a type of diabetes that develops when women experience unusually high glucose levels during pregnancy) during the second trimester of pregnancy (13-27 weeks). The first step is a glucose challenge test, taken by measuring glucose levels one hour after ingesting a sugary substance such as glucola. If results are abnormal (≥7.8 mmol/L), a second oral glucose tolerance test (OGGT) is taken.

Participants in the study were followed up until March 31, 2008, providing information reflecting cardiovascular disease development for a median of 12.3 years after childbirth. “If you followed 10,000 people for one year, 4.2 of them would have an event,” Dr. Shah explains. “If you followed those 10,000 people for 10 years, 42 of them would have an event…In other words, these are extremely rare events.”

Although the differences were minor—absolute risk was 0.16% and 0.05% for women with gestational diabetes and women who received an OGGT, respectively—the results indicate a need for further research. "We shouldn't be ignoring these mild abnormalities during pregnancy,” Dr. Shah says. “(They) may benefit from extra surveillance and/or cardiovascular disease screening.”

More information is needed to establish the exact relationship between glucose intolerance and cardiovascular disease. In the meantime, proper nutrition and exercise may reduce your risk for both gestational diabetes and cardiovascular disease.

Read more about gestational diabetes and cardiovascular disease.

There may be added benefits to that diet you’re on—following a Mediterranean-style diet may put you at a lower risk of Alzheimer’s disease. Researchers from the Taub Institute for Research on Alzheimer’s Disease and the Aging Brain at Columbia University Medical Center found that individuals who adhered to a Mediterranean-type diet in addition to exercise were 60% less likely to develop Alzheimer’s.

Alzheimer’s disease is an irreversible degenerative disease affecting the brain, often causing severe memory loss (a result of damage to the hippocampus) and destroyed cognitive ability. Alzheimer’s, which typically begins around age 60, is the leading cause of dementia among the elderly.

Damage to the brain may begin as early as 20 years before any complications are detected. Alzheimer’s begins when neural tangles form in the entorhinal cortex. This causes the neurons to function less efficiently, and the neurons eventually die, causing these areas of the brain to shrink.

“We know that some part of Alzheimer’s is related to genetic changes and as time goes on we discover more and more of these changes,” explains lead author Nikos Scarmeas, M.D., and associate professor of clinical neurology at Columbia. “But it is also possible that non-genetic changes, including lifestyle and behavior, may also be affecting our brain health and our risk of developing brain diseases like Alzheimer’s.”

The study examined 1,880 multi-ethnic individuals, average age 77, from Northern Manhattan in New York City. The group was divided into two smaller groups, for which information on both physical activity and mental status was available. Participants did not show signs of dementia at the beginning of the study, and were followed from 1996 to 2006, measured every 18 months for neurological changes.

Participants were measured for physical activity level (no physical activity, light activity such as golfing, moderate activity like biking, or vigorous activity such as jogging) and how well they stuck to the diet (on a scale of 0-9). Diet scores were higher for individuals who consumed more fruits, vegetables, legumes and fish, and less meat, dairy and saturated fats.

“Often times people who exercise also follow a healthy diet and vice versa,” Scarmeas says. “We wanted to tease out which of these two behaviors may be associated with lower risk for AD, or if the combination of the two is associated with decreased risk even further.”

Individuals who had low physical activity had a 29-41% lower risk of developing Alzheimer’s disease than those who  were physically inactive, while individuals with “much” physical activity further decreased their risk by 37-50%. Strongly following a Mediterranean diet was associated with a 40% risk reduction for Alzheimr’s. Individuals with high diet adherence and high activity individuals showed a much lower absolute risk than those with low diet adherence and activity status, reduced from 21% to 9%.

According to Scarmeas, this study emphasizes the importance of a healthy lifestyle. "We need to understand and learn more about the exact biological mechanisms that may connect physical activity and diet with the biological changes of Alzheimer's disease," he says. "This study is important because it shows that people may be able to alter their risk of developing Alzheimer's by modifying their lifestyles through diet and exercise."

Learn more about Alzheimer's disease by visiting Healia's Alzheimer's Community.

Sunshine actually may put pep in your step and improve your thinking skills. A study by the University of Alabama at Birmingham shows that the amount of sunlight you are exposed to may boost your cognitive ability.

The study examined the seasonal role and amount of sunlight exposure (referred to as insolation) on patients’ energy levels and cognitive ability. Researchers hypothesized that greater insolation would boost both energy and mental functioning.

This was found to be very true for patients with depression. Sunlight plays a huge role in the body’s circadian (daily) rhythm. Alzheimer’s, for example, has been associated with low blood flow to the cerebrum, yet another of sunlight’s effects.

Individuals who got less sun exposure were more likely to experience an irregular circadian rhythm, similar to Seasonal Affective Disorder (SAD), also known as seasonal depression. Several studies have been conducted in the past to examine the effect of sunlight and seasonal changes on mood in people with depression, but this was the first to study the effects of both on thought processes.

"We think some of the same physiological mechanisms that affect depression also affect cognitive function,” says Shia Kent, author of the study and doctoral candidate at the School of Public Health at the University of Alabama at Birmingham. “These same hormone systems have been implicated in a number of mental disorders and cognitive disorders.”

One key to this relationship lies in the suprachiasmatic nuclei (SCN), a region of the brain responsible for processing information from the eyes and stimulating hormones.One of the SCN’s roles is to prevent the pineal gland from converting serotonin into melatonin, a hormone that triggers sleepiness.

The retina sends light information to the SCN, slowing the brain’s production of melatonin and serotonin—both associated with cognitive functioning—during the day or in a well-lit room. Without this process, the body’s natural rhythm is disrupted. Similar disruptions have been associated with sleep disorders and memory problems in otherwise healthy individuals.

Participants in the study hailed from an area of the United States known as the “stroke belt”—Arkansas, Louisiana, Tennessee, Mississippi, Alabama, Georgia, North Carolina, and South Carolina. Nearly 14,500 men and women over age 45 (44% African-American, 56% white) with no history of a stroke included in the final model were questioned using the Reasons for Geographic and Racial Differences in Stroke (REGARDS) Study.

Cognitive functioning was measured via telephone interviews, while weight, height and blood pressure were measured in-home prior to the study. Participants were then followed for the next two weeks, while researchers measured insolation (with the help of NASA satellite and ground data) and thinking ability (using questionnaires).

Solar radiation was measured eight times daily, at 3-hour intervals. Typical insolation values were 25,000-30,000 KJ/m² in late spring and early summer, and 8,000-10,000 KJ/ m² in the central U.S. Short-term and long-term memory were measured using a six-question test. Answering four or less correctly indicated impairment. 

Based on their findings, researchers reported that low sunlight exposure was a higher likelihood of cognitive impairment for subjects with depression, including those who were prone to SAD. Roughly 18% of participants with any form of depression were classified as having impaired thinking in response to lower insolation, regardless of the season.

“This is speculation,” says Kent, “but those who have cognitive impairment could be helped with sunlight."

 

Learn more about Seasonal Affective Disorder (SAD) in Healia Communities.