Population prevalence, attributable risk, and attributable risk percentage for high methylmalonic acid concentrations in the post-folic acid fortification period in the US

• Main Authors: Ganji Vijay, Kafai Mohammad R
• Format: Article
• Language: English
• Published: BMC 2012-01-01
• Series: Nutrition & Metabolism
• Subjects: Age; methylmalonic acid; NHANES; population attributable risk; population attributable risk percentage
• Online Access: http://www.nutritionandmetabolism.com/content/9/1/2

<p>Abstract</p> <p>Background</p> <p>Serum methylmalonic acid (MMA) is regarded as a sensitive marker of vitamin B-12 status. Elevated circulating MMA is linked to neurological abnormalities. Contribution of age, supplement use, kidney dysfunction, and vitamin B-12 deficiency to high serum MMA in post-folic acid fortification period is unknown.</p> <p>Methods</p> <p>We investigated prevalence, population attributable risk (PAR), and PAR% for high MMA concentrations in the US. Data from 3 cross-sectional National Health and Nutrition Examination Surveys conducted in post-folic acid fortification period were used (<it>n </it>= 18569).</p> <p>Results</p> <p>Likelihood of having high serum MMA for white relative to black was 2.5 (<it>P </it>< 0.0001), ≥ 60 y old persons relative to < 60 y old persons was 4.0 (<it>P </it>< 0.0001), non-supplement users relative to supplement users was 1.8 (<it>P </it>< 0.0001), persons with serum creatinine ≥ 130 μmol/L relative to those with < 130 μmol/L was 12.6 (<it>P </it>< 0.0001), and persons with serum vitamin B-12 < 148 pmol/L relative to those with ≥ 148 pmol/L was 13.5 (<it>P </it>< 0.0001). PAR% for high MMA for old age, vitamin B-12 deficiency, kidney dysfunction, and non-supplement use were 40.5, 16.2, 13.3, and 11.8, respectively. By improving serum vitamin B-12 (≥ 148 pmol/L), prevalence of high MMA would be reduced by 16-18% regardless of kidney dysfunction.</p> <p>Conclusions</p> <p>Old age is the strongest determinant of PAR for high MMA. About 5 cases of high serum MMA/1000 people would be reduced if vitamin B-12 deficiency (< 148 pmol/L) is eliminated. Large portion of high MMA cases are not attributable to serum vitamin B-12. Thus, caution should be used in attributing high serum MMA to vitamin B-12 deficiency.</p>