Calcium supplements and cardiovascular risk?

On July 31, 2010, in Minerals, by Andrea

A prime example of how media will take a study and leave out key points in order to scare people.  Gotta love it.

All over, the news outlets are talking about how people should maybe lay off the calcium because there may be too much risk for a cardiovascular incident versus osteoporosis prevention.  What they conveniently forget to mention is that the calcium used did not contain any vitamin D, which is pretty much standard faire in the US.  Vitamin D is renowned for lowering cardiovascular risk.. perhaps this study highlights that now more than ever?  I can say fairly confidently that people are waking up to the need of vitamin D and post-WLS folks are some of the most educated in that realm.  WTG WLSers!

Additionally, it should be noted that the problem is with fluctuating serum calcium levels — something that doesn’t happen as often with post-WLS patients as our absorption does not work the same way.  Food for thought:  how many post-ops, people who routinely take 1500-2000mg of calcium citrate a day (or should be..) are dropping like flies with heart disease?  Not many.

Am I worried?  No.

Continue reading »

Yet more evidence for D

On January 7, 2010, in Fat Solubles, Vitamins, by Andrea

At some point, people are going to figure out that vitamin D is important.  I don’t know when, but they will, and it will be tested for all people — not just those of us who scream loudly for it, and not just by those docs that pay attention to the studies.

Pay attention — vitamin D has been linked to cardiovascular disease, bone health, depression, stroke, diabetes, and many types of cancer.

Two reports in one day — one video and one report from Medscape — that show a corollary between heart disease in blacks and deficiency in vitamin D.

First, from Medscape:

Could Vitamin-D Deficiency Account for Higher CV Mortality in Blacks?

Sue Hughes

January 6, 2010 (Rochester, New York)Another paper suggesting a link between low levels of vitamin D and cardiovascular mortality has been published [1]. It also suggests that low vitamin-D levels may contribute to the increased cardiovascular mortality seen in the black population.

The study, published in the January-February 2010 issue of Annals of Family Medicine, was conducted by Drs Kevin Fiscella (University of Rochester School of Medicine, NY) and Peter Franks (University of California, Davis).

Fiscella commented to heartwire : “We know that people with darker skin have lower vitamin-D levels. And we know that African Americans have higher rates of cardiovascular disease than the white population. In our study, just two factors–poverty and low vitamin-D levels–seemed to explain the higher risk of cardiovascular mortality in the black population.”

In the paper, the authors note that low levels of vitamin D have been linked to cardiovascular disease and to cardiovascular risk factors such as obesity, hypertension, diabetes, peripheral arterial disease, and chronic renal disease.

They conducted a retrospective cohort study to examine the association of serum 25(OH)D levels with cardiovascular mortality and to look at the possible contribution of vitamin-D levels to black-white disparities in cardiovascular mortality. They used baseline data from the National Health and Nutrition Examination Survey collected between 1988 and 1994 (NHANES III) and data on cause-specific mortality through 2001 from the National Death Index. Complete data for all variables were available on 15 363 persons.

Results showed that participants with 25(OH)D levels in the lowest quartile (mean 13.9 ng/mL) compared with those in the three higher quartiles (mean 21.6, 28.4, and 41.6 ng/mL) had higher adjusted risk of cardiovascular death. There appeared to be a threshold effect, with little reduction in cardiovascular deaths above the 25th percentile. Those in the lowest quartile had an adjusted cardiovascular mortality risk 40% higher than the other three 25(OH)D quartiles (95% CI 16%–69%; p=0.001).

The relationship between race and cardiovascular mortality and the potential mediating effect of 25(OH)D was examined in a series of nested models. In the model adjusting only for outside variables (age, sex, month, and region), blacks showed significantly higher cardiovascular mortality than whites (incident rate ratio [IRR] 1.38). When 25(OH)D was added, there was a significant reduction of around 60% in the risk associated with black race (IRR 1.14), and when 25(OH)D and income were added together to the model, the increased risk in blacks was completely eliminated (IRR 1.01). The authors say this suggests that low 25(OH)D levels and poverty exert separate, additive effects on black cardiovascular mortality.

They add: “These findings are consistent with the notion that higher cardiovascular risk for blacks is partly related to lower levels of 25(OH)D,” but they add that supplements higher than those currently recommended would be needed to substantially increase levels among those in the lowest quartile.

They note that there are several sources of potential residual confounding in their analysis. For example, low 25(OH)D levels may represent a marker for poor health, or poor health may result in reduced sun exposure and consequent lower 25(OH)D levels. And unmeasured risk factors could also confound the results.

They point out that there are limited data from randomized controlled trials regarding the impact of vitamin-D supplementation on cardiovascular disease. But a meta-analysis of randomized trials of vitamin-D supplementation for other purposes, such as improvement in bone density and reduction in fractures, has shown a reduction in all-cause mortality, and other studies have suggested that vitamin-D supplementation may be associated with reductions in systolic blood pressure and reductions in proteinuria among patients with chronic kidney disease. It has also been suggested that statins represent analogs of vitamin D, they add.

Is It a Causal Relationship?

To heartwire , Fiscella commented: “If vitamin D is proven to be a causal risk factor (and this remains to be shown), then supplementing with vitamin D could help reduce cardiovascular disease and mortality in the whole population and to reduce the disparity we see between whites and blacks.

“We desperately need a randomized trial to look at vitamin-D supplementation in reducing cardiovascular disease. We have had a lot of false hopes before with vitamins, but there is a lot of basic science and epidemiology supporting a possible role for vitamin D in cardiovascular disease. There are many studies linking low vitamin-D levels to diabetes, hypertension, and peripheral vascular disease, and all of these are drivers of cardiovascular disease.”

He added: “We know low vitamin-D levels are implicated in poor health, but we don’t know which way that relationship works. Is it the lack of vitamin D that causes illness, or is it that people in poor health have suppressed appetites and don’t go outside enough and therefore don’t take in enough vitamin D?. And if vitamin-D deficiency is causal, will supplementation have a relatively quick benefit, or would you need to take it for years to see a benefit”?

Fiscella pointed out that the dose of vitamin D needed is also unknown. “The current recommendations are for a vitamin D intake of 400 units daily. But it may take much higher doses than this to have an effect on cardiovascular disease.”

And then from CNN.com:

Fit AND Fat?

On January 7, 2010, in Uncategorized, by Andrea

The usual standard of fitness, the BMI, or Body Mass Index chart, is a crappy indicator.  We all know this.  I mean, anything that puts celebrities like Arnold Schwarzenegger in the “obese category” is not a good indicator of health.  So this is a big “duh” for many of us.

But I always said I had been a “healthy” fat person.  And given my lack of co-morbs prior to surgery, I was.  I had low blood pressure, no signs of heart disease, low cholesterol, no diabetes — even LOW blood sugar rather than trending upward sugar levels, no sleep apnea, no PCOS — but would I have stayed that way?

So again, is there a question of Fit, but Fat?

It’s interesting to me that there were two different things about this — both from two different countries, studying two different genders, that say the complete opposite of each other.  Now given, one is a short-term glimpse of life and one is a long-term study.  I’m more apt to look at the long-term study, but the video does bring in the relevance of waist circumference versus BMI (although I’m not certain it would have made a difference in either case), but it does bring the point home that a different measure should be made.

From Medscape:

Overweight, Obesity up CV Risk Regardless of Metabolic Markers in Long-Term Study

Michael O’Riordan

January 5, 2010 (Uppsala, Sweden) — Middle-aged men with the metabolic syndrome are at an increased risk of cardiovascular disease and death regardless of their body-mass index (BMI), new research shows [1]. On the flip side of that combination, investigators also showed that overweight and obese individuals without the metabolic syndrome are at an increased risk of cardiovascular events and death.

Publishing their results online December 28, 2009 and in the January 19, 2010 issue of Circulation, Dr Johan Ärnlöv (Uppsala University, Stockholm, Sweden) and colleagues say the “data refute the notion that overweight and obesity without the metabolic syndrome are benign conditions.”

As the researchers note in their paper, previous studies have shown that obese individuals without the metabolic syndrome–sometimes referred to metabolically healthy obese, or even healthy fat–were not at an increased risk of cardiovascular disease events. Follow-up in these studies was around 13 years, leaving some question as to the long-term impact of different BMI/metabolic-syndrome combinations.

In this new Swedish examination, cardiovascular risk factors were assessed in 1758 middle-aged individuals without diabetes in the Uppsala Longitudinal Study of Adult Men (ULSAM). During a median follow-up of 30 years, 788 participants died and 681 developed cardiovascular disease. In hazard models that adjusted for age, smoking, and LDL cholesterol, metabolic syndrome was associated with an increased risk in normal, overweight, and obese individuals. As noted, even obese and overweight individuals without metabolic syndrome were at an increased risk for death and cardiovascular events.

ULSAM: Death and Major Cardiovascular Events (HR, 95% CI) in the Different Groups

End point Normal weight without metabolic syndrome Normal weight with metabolic syndrome Overweight without metabolic syndrome Overweight with metabolic syndrome Obese without metabolic syndrome Obese with metabolic syndrome
Total death Referent 1.28 (0.90–1.82) 1.21 (1.03–1.40) 1.53 (1.19–1.96) 1.65 (1.03–2.66) 2.43 (1.81–3.27)
CV death Referent 1.77 (1.11–2.83) 1.44 (1.14–1.83) 2.19 (1.57–3.06) 1.20 (0.49–2.93) 3.20 (2.12–4.82)
Major CV events Referent 1.63 (1.11–2.37) 1.52 (1.28–1.80) 1.74 (1.32–2.30) 1.95 (1.14–3.34) 2.55 (1.82–3.58)

The researchers note that there appeared to be a lag time of approximately 10 years before the Kaplan–Meier curves for overweight and obese individuals without the metabolic syndrome diverged from the curve of normal-weight participants without the syndrome.

“This could be important, because it is possible that the transition from overweight/obesity without metabolic derangements to overt cardiovascular disease is a pathological process that spans several decades,” write Ärnlöv and colleagues.

They note that based on previous studies, weight loss in these so-called metabolically healthy obese and overweight individuals had been questioned, with some researchers even suggesting it might be harmful for them to lose weight. Based on their results, however, the “potential benefits of diagnosing metabolically healthy obese in clinical practice appears limited,” and the data do not support the existence of a healthy obese phenotype based on the absence of metabolic syndrome or insulin resistance.

And conversely, from MSNBC.com:

Visit msnbc.com for breaking news, world news, and news about the economy

Obesity as serious as smoking

On January 6, 2010, in Uncategorized, by Andrea

I could have told them this..  And probably saved them some money in the process.

Duh?

On December 25, 2009, in Uncategorized, by Andrea

Really?  Must be a European thing, cause I’ve not seen a whole lotta PSA’s saying “gain weight or you’re gonna die from malnourishment!”

From Medical News Today:

Adverse Consequences Of Obesity May Be Greater Than Previously Thought, UK

Article Date: 25 Dec 2009 – 0:00 PST

The link between obesity and cardiovascular mortality may be substantially underestimated, while some of the adverse consequences of being underweight may be overstated, concludes a study published on bmj.com .

This means that the adverse influence of higher BMI and obesity in a population is of greater magnitude than previously thought, say the authors.

Numerous studies have already investigated the link between body mass index (BMI) and mortality. They show that high BMI is associated with higher rates of death from cardiovascular causes, diabetes, and some cancers, while low BMI is associated with increased mortality from other causes, such as respiratory disease and lung cancer.

But there are inconsistencies in the evidence that low body mass index actually increases the risk of causes of death such as respiratory disease and lung cancer.

Some researchers argue that this association may be biased by a process called reverse causality, where a severe illness, such as lung cancer, leads to both weight loss and higher mortality. Other factors such as smoking and poor socioeconomic circumstances may also lead to biasing estimates. This is known as confounding.

So a team from the University of Bristol and the Karolinska Institute in Sweden set out to obtain a valid estimate of the association between body mass index (BMI) and mortality by comparing, for over one million Swedish parent-son pairs, the BMI of the sons as young adults with mortality among their parents.

Using offspring BMI as an indicator of parental BMI avoids problems of reverse causality and is less influenced by confounding, explain the authors.

Their analysis shows strong associations between high offspring BMI (used as a so-called instrumental variable) and parental mortality from cardiovascular disease, diabetes, and some cancers, as reported in other studies of own BMI with mortality. However, unlike previous studies, there was no evidence of an association between low BMI and an increased risk of respiratory disease and lung cancer mortality.

These findings suggest that the apparent adverse consequences of low BMI on respiratory disease and lung cancer mortality may be overstated, whereas the adverse consequences of higher BMI on cardiovascular disease mortality may be substantially underestimated, say the authors.

These conclusions have important implications for public health practice because they suggest that reducing population levels of overweight and obesity (or preventing their rise) will have a considerable benefit to population health, they add. Suggestions to the contrary, which have received considerable media attention over recent years, are probably misguided.

Link to paper

Source
British Medical Journal