HEALTH NEWS

Study Title:

Low vitamin B12 predicts incident fractures in elderly men: the MrOS Sweden.

Study Abstract

In a population-based study on cobalamin status and incident fractures in elderly men (n = 790) with an average follow-up of 5.9 years, we found that low levels of metabolically active and total cobalamins predict incident fractures, independently of body mass index (BMI), bone mineral density (BMD), plasma total homocysteine (tHcy), and cystatin C.

INTRODUCTION:

Cobalamin deficiency in elderlies may affect bone metabolism. This study aims to determine whether serum cobalamins or holotranscobalamin (holoTC; the metabolic active cobalamin) predict incident fractures in old men.

METHODS:

Men participating in the Gothenburg part of the population-based Osteoporotic Fractures in Men (MrOS) Sweden cohort and without ongoing vitamin B medication were included in the present study (n = 790; age range, 70-81 years).

RESULTS:

During an average follow-up of 5.9 years, 110 men sustained X-ray-verified fractures including 45 men with clinical vertebral fractures. The risk of fracture (adjusted for age, smoking, BMI, BMD, falls, prevalent fracture, tHcy, cystatin C, 25-OH-vitamin D, intake of calcium, and physical activity (fully adjusted)), increased per each standard deviation decrease in cobalamins (hazard ratio (HR), 1.38; 95 % confidence intervals (CI), 1.11-1.72) and holoTC (HR, 1.26; 95 % CI, 1.03-1.54), respectively. Men in the lowest quartile of cobalamins and holoTC (fully adjusted) had an increased risk of all fracture (cobalamins, HR = 1.67 (95 % CI, 1.06-2.62), holoTC, HR = 1.74 (95 % CI, 1.12-2.69)) compared with quartiles 2-4. No associations between folate or tHcy and incident fractures were seen.

CONCLUSIONS:

We present novel data showing that low levels of holoTC and cobalamins predicting incident fracture in elderly men. This association remained after adjustment for BMI, BMD, tHcy, and cystatin C. However, any causal relationship between low cobalamin status and fractures should be explored in a prospective treatment study.

From press release:

Older men who have low levels of vitamin B12 have a higher risk of having fractures. These are the findings of researchers at the Sahlgrenska Academy as a part of an international study of a total of 1000 older men.

Osteoporosis is one of the world's most widespread diseases, and intensive research is under way worldwide to identify its causes and to be able to prevent fractures.

In an extensive study, researchers at the Sahlgrenska Academy at the University of Gothenburg can now show that low levels of vitamin B12 in the blood increases the risk of fractures in older men.

This study is a part of an international research project initiated by the National Institutes of Health (NIH) in the US and comprises 11,000 men in total. In their part of the study, the Gothenburg researchers studied 1,000 Swedish men, MrOS Sweden, with an average age of 75, and used various methods to analyze the blood concentrations of the B vitamins B12 and folate, which are found in our food naturally.

The results show that the risk of suffering a fracture six years later was higher among men who had low B12 levels at the beginning of the study than men with normal B12 levels. In the quartile with the lowest B12 content, the risk was elevated by approximately 70 percent compared with the others. The risk increase pertained primarily to fractures in the lumbar region, where the risk increase was up to 120 percent.

"The higher risk also remains when we take other risk factors for fractures into consideration, such as age, smoking, BMI, BMD (bone mineral density), previous fractures, physical activity, the D-vitamin content in the blood and calcium intake," says Catharina Lewerin, researcher at the Sahlgrenska Academy.

Does this mean that older men can prevent fractures by eating more vitamin B12? "It has not been scientifically established, but such studies are under way, including one large Dutch study where older individuals over the age of 65 are treated with both vitamin B12, folic acid and vitamin D to investigate the occurrence of fractures.

"Right now, there is no reason to eat more vitamin B12, but rather treatment shall only be applied in confirmed cases of deficiencies and in some cases to prevent deficiencies. For anyone who wants to strengthen their bones and prevent fractures, physical activity 30 minutes a day and quitting smoking is good self care," says Catharina Lewerin.

New method In this study, the researchers used a relatively new method called holotranscobalamin, which measures the amount of vitamin that is taken up in the cells, which is considered to be a more sensitive test for B12 deficiency.

Study Information

Lewerin C, Nilsson-Ehle H, Jacobsson S, Johansson H, Sundh V, Karlsson MK, Ljunggren O, Lorentzon M, Kanis JA, Lerner UH, Cummings SR, Ohlsson C, Mellström D.
Low holotranscobalamin and cobalamins predict incident fractures in elderly men: the MrOS Sweden.
Osteoporos Int.
2013 October
University of Gothenburg