Body mass index (BMI) and waist circumference are each independently associated with an increased risk for atherothrombosis in patients with Type 2 diabetes mellitus and coronary artery disease (CAD), research suggests.

The finding supports a direct adverse impact of central obesity on cardiovascular (CV) disease outcomes, and suggests that both BMI and waist circumference should be included as potential CV risk factors in longitudinal analyses.

The study was undertaken by Jeanine Albu (Columbia University, New York, USA) and team and examined the association between anthropometric measures and CV risk among 2273 participants in the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) study.

All participants had Type 2 diabetes and documented CAD; their mean age at baseline was 62 years, two-thirds were non-Hispanic White, and 71% were men. The median time from diagnosis of diabetes was 10.4 years.

In all, 90% of participants were overweight, defined as a BMI of 25 kg/m2 or above, and 68% of men and 89% of women had waist circumferences in the high-risk range (?102 and ?88 cm, respectively).

Using multiple linear regression models that adjusted for a raft of potential confounders, Albu’s team found that either a higher BMI or a higher waist circumference were significantly associated with CV risk factors, including higher triglycerides, insulin, plasminogen activator inhibitor-1 activity and antigen, C-reactive protein, and fibrinogen.

A higher BMI was also associated with a higher diastolic BP, while a higher waist circumference was associated with a lower high-density lipoprotein cholesterol level.

“These covariates alone explained 3??”16% of the variance in the risk factors,” remark Albu et al, writing in the journal Obesity.

The authors admit that their study is limited by its cross-sectional design and call for longitudinal data to clarify whether baseline BMI and waist circumference, or changes in them, will independently predict CV disease events and death in this patient group.

They conclude: “Overall, our findings support the hypothesis that the novel atherothrombotic risk factors could be important mediators of the relationship between obesity and CV disease outcomes in patients with established Type 2 diabetes and CAD.”

MedWire (www.medwire-news.md) is an independent clinical news service provided by Current Medicine Group, a trading division of Springer Healthcare Limited. © Springer Healthcare Ltd; 2009

Free abstract

When it comes to foot care diabetes complicates things. In many cases, there is reduced blood flow to the nerve endings and damage done by high glucose levels.

The lining of the blood vessels absorb more glucose than normal, because they do not need insulin to absorb glucose, as other cells do. Eventually, the lining becomes thicker than normal, but at the same time, it becomes weaker.

The results can include the collapse of the tiny blood vessels or disease in the major arteries. In some cases, such as in the back of the eye, new blood vessels form as the body tries to nourish cells and nerve endings, but the new blood vessels are even more fragile.

When the blood flow to the nerve endings is cut off, the nerves can die. The result is called neuropathy. They symptoms may include reduced sensation in the feet, a feeling of pins and needles, burning, stinging and coldness. The feet may at first become more sensitive to pain, but eventually, numbness occurs.

The feet often swell, which further reduces blood flow, if the shoes are tight and inflexible. For the best foot care diabetes experts recommend shoes with a wide, deep toe box and adjustable straps to accommodate swelling.

Seamless socks are also recommended, because the pressure from a seam can cause pain, in the early stages. In the late stages, the pain may go unnoticed and a blister may form.

Fungal infections are more likely in some patients, because of increased sweating, a common symptom in diabetic patients. The warm dampness creates a perfect environment for fungus to grow.

Special socks made of a wicking material are available for diabetics, as well as other people that suffer from sweaty feet. The material wicks or pulls perspiration away from the feet.

With proper foot care diabetes patients can reduce their risks of complications that could lead to gangrene and amputation. Early diagnosis is the key. If you are physically unable to clean and examine your feet on a daily basis, you should ask for help.

While some diabetic complications may be unavoidable, research indicates that amputations are for the most part, avoidable. Prevention is more effective than treating ulcerations. They just don’t heal quickly and the infection often spreads deeper into delicate tissues.

Although addressing perspiration is important, it is also important to address the issue of dry skin, which is often present on the heels and sides of the feet. There are special foot care diabetes moisturizers that also help to improve blood flow and warm the feet.

It’s important to choose your moisturizer carefully. Many of the lotions on the market do nothing but trap in perspiration. If the lotion makes your skin feel too greasy, then it probably contains petrolatum. It’s not actually a moisturizing ingredient, but it is very inexpensive. So, many companies still use it.

For foot care diabetes specialists recommend that you contact your podiatrist immediately if you see swelling, redness or other signs of infection. Don’t wait. Quick treatment is essential.

I’m working with an athlete who has recently been diagnosed as a diabetic and is training for an Ironman. He is also new to triathlons and all the training and logistics that come with it.

Last week I got an email from him about two problems with his diabetes management:

?? 1. High glucose levels on his early bike sessions

?? 2. Hypoglycemia during swim workouts done at lunch time

1) Hyperglycemia early in the morning is very common in diabetics. Also known as the Dawn Phenomenon, it is the result of decreased insulin sensitivity and changes in the levels of various hormones in the early morning hours (GH, Cortisol, Glucagon), which can lead to the overproduction of glucose by the liver and to the underutilization of glucose by peripheral tissues.?

Since the bike workouts are only about one hour, there is no need to have a big breakfast before these. So he was instructed to get a big breakfast after those workouts, taking a couple of extra ultra-fast insulin with it, and check blood glucose levels 2 hours after the meal to make sure it was all absorbed.

2) Hypoglycemia during swim workouts done at lunch time

For the second issue, there is also a link between the situations that are causing the hypoglycemia during the swim.

First of all, swimming brings with it a higher metabolism rate and a higher number of muscles involved in the work compared with running or biking. When you swim you are using many small muscles, which make the glycogen consumption a bit higher than during biking or running, thus making swimming the discipline that causes a bigger drop in blood glucose levels for the first hour of training.

Another reason is that on some days this athlete is training in the morning (when the dawn phenomenon occurs) as well. So by the time he gets in the pool, not only is his metabolism higher but his insulin sensitivity is high too.

I remember that back in my training days it didn’t matter how high my blood glucose levels were before a workout - if I didn’t eat anything before the session I would end up with a hypo.

The advice for my athlete was:

1. If blood glucose level is >180: Take a bottle of maltodextrin/sports drink (with 200+ calories) to the pool and drink it halfway through the session.

2. If blood glucose level is <180: Eat a small snack before training AND take a bottle of sports drinks to the pool, drinking it halfway through the session.

Connecting the two problems:

It is very unlikely that you will get an HIPO by training on an empty stomach in the morning, unless of course the workout is longer than 1 hour or you woke up with an extremely low blood glucose level. Swimming is the discipline that has a stronger impact on your blood glucose levels if you were to do them all at a similar intensity.?

One way to manage those two problems is by working on the training schedule. This athlete has only access to a pool at lunch time and has a group bike to train with in the morning. But if you can swim in the morning and run/bike at lunch/evening, that would keep your blood glucose levels steadier.

Plus, swimming in the morning is always best for those without a swimming background since you get to train on a fresher body, struggle less to float in the water, therefore getting more quality out of the sessions.