Vitamin D Enhances Effect of Antidepressant
Forty-two patients (mean age, 39 years) with major depressive disorder were randomly assigned to receive, in double-blind fashion, 1500 IU per day of vitamin D3 plus 20 mg per day of fluoxetine or fluoxetine alone (control group) for 8 weeks. The mean serum 25-hydroxyvitamin D concentration at baseline was 23 ng/ml, suggestive of low or borderline-low vitamin D status. The severity of depression was assessed every 2 weeks, using the 24-item Hamilton Depression Rating Scale (HDRS) and the 21-item Beck Depression Inventory (BDI). The mean improvement on the HDRS and BDI was significantly greater in the vitamin D group than in the control group at weeks 4, 6, and 8.
Comment: Previous research has suggested that vitamin D has a modest antidepressant effect, although findings have not been consistent and the mechanism of action is not known. The results of the present study suggest that vitamin D supplementation can enhance the effect of a selective serotonin-reuptake inhibitor in patients with major depressive disorder who have low to borderline-low vitamin D status. Further research is needed to determine whether vitamin D would have a beneficial effect in patients with normal vitamin D status.
Khoraminya N et al. Therapeutic effects of vitamin D as adjunctive therapy to fluoxetine in patients with major depressive disorder. Aust N Z J Psychiatry. 2013;47:271–275.
Poor Quality Control for Vitamin D Supplements
Five pills from each of 15 bottles of over-the-counter vitamin D3 (1000, 5000, and 10,000 IU) purchased at 5 stores in Portland, Oregon, were analyzed for their vitamin D content. The potency of the pills ranged from 9% to 146% of the amount listed on the label. Only slightly more than half of the pills met U.S. Pharmacopeia (USP) standards, which require that pills contain 90% to 110% of the amount listed on the label.
Comment: In a previous study, evaluation of compounded vitamin D supplements used in a clinical trial revealed that only one-third of the pills met USP standards. The results of the present study indicate that the reliability of commercial over-the-counter vitamin D products is not much better. The use of products that contain substantially less or substantially more vitamin D than the amount listed on the label could increase the risk of both treatment failure and toxicity. Companies that sell vitamin D should regularly analyze their products, and practitioners should only use those products that are regularly analyzed.
Leblanc ES et al. Over-the-counter and compounded vitamin D: is potency what we expect? JAMA Intern Med. 2013;173:585–586.
Probiotic Effective Against Bacterial Vaginosis
Five hundred forty-four women (mean age, 33 years) with bacterial vaginosis diagnosed by the Amsel criteria or the Nugent scoring system were randomly assigned to receive, in double-blind fashion, 2 oral capsules per day of the combination of Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14 (GR-1/RC-14; more than 109 colony-forming units of each strain per capsule) or placebo for 6 weeks. At the end of the treatment period, the proportion of women who had normal vaginal flora was significantly higher in the probiotics group than in the placebo group (61.5% vs. 26.9%; p < 0.001). Six weeks after treatment was completed, the proportion of women who had normal vaginal flora was again significantly higher in the probiotics group than in the placebo group (51.1% vs. 20.8%; p < 0.001).
Comment: Bacterial vaginosis is a common condition that is difficult to eradicate. The initial response to antibiotic therapy (such as metronidazole) is only 70% to 80%, and among those who do respond, 30% and 50% experience a recurrence within 3 and 12 months, respectively. GR-1/RC-14 appears to have a number of properties that promote urogenital health. In a previous study, administration of this preparation during and after metronidazole treatment markedly reduced the recurrence rate of bacterial vaginosis, when compared with metronidazole alone. The results of the present study indicate that GR-1/RC-14 may be an effective alternative to antibiotic therapy in women with bacterial vaginosis.
Vujic G et al. Efficacy of orally applied probiotic capsules for bacterial vaginosis and other vaginal infections: a double-blind, randomized, placebo-controlled study. Eur J Obstet Gynecol Reprod Biol. 2013;168:75–79.
Probiotics Prevent Common Cold
Eighty children (aged 8–13 years) were randomly assigned to receive, in double-blind fashion, a capsule containing 109 organisms each of Lactobacillus acidophilus and Bifidobacterium bifidum (Infloran, Berna, Switzerland) or placebo twice a day for 3 months. The proportion of children who developed at least one symptom of a cold during the study was significantly lower in the probiotics group than in the placebo group (77% vs. 95%; p < 0.05). Children in the probiotics group had a significantly lower risk of fever, cough, rhinorrhea, and school absence compared with children in the placebo group.
Comment: This study confirms the results of previous research indicating that probiotics can prevent upper respiratory tract infections in children. Other strains that have been found to be effective include L. rhamnosus GG and the combination of L. acidophilus NCFM and B. animalis subsp lactis Bi-07. Probiotics are thought to work by enhancing immune function.
Rerksuppaphol S, Rerksuppaphol L. Randomized controlled trial of probiotics to reduce common cold in schoolchildren. Pediatr Int. 2012;54:682–687.
Processed Meat and COPD
Two hundred seventy-four patients (mean age, 68 years) hospitalized for the first time for chronic obstructive pulmonary disease (COPD) provided information on dietary intake of cured meat during the previous 2 years, and were followed for a median of 2.6 years. After adjustment for age, lung function (FEV1), and total caloric intake, higher intake of cured meat (more than the median value of 23 g per day), as compared with lower intake, was associated with a doubling of the risk of readmission for COPD (adjusted hazard ratio = 2.02; p = 0.001).
Comment: Curing of meat usually involves the addition of nitrites or nitrates. In rats, the addition of sodium nitrite to drinking water at a level higher than that consumed in a typical human diet resulted in the development of pulmonary emphysema. Nitrites are prooxidants that generate reactive nitrogen species such as peroxynitrite, which are capable of producing lung damage and are thought to play a role in the pathogenesis of COPD. Two prospective cohort studies in the US found that consumption of higher amounts of cured meat was associated with a higher risk of developing COPD. The results of the present study demonstrate that consumption of cured meat is also associated with increased severity of the disease.
De Batlle J et al. Cured meat consumption increases risk of readmission in COPD patients. Eur Respir J. 2012;40:555–560.
Iron Supplements Improve Chronic Cough
Twenty nonsmoking women (mean age, 38 years) with iron deficiency (serum ferritin < 15 ng/ml; mean, 9.3 ng/ml) and chronic unexplained cough that had failed to respond to empirical treatment with an antihistamine and a proton pump inhibitor received supplemental iron (1 mg per kg of body weight per day, corresponding to one or two 330 mg ferrous sulfate tablets per day) for 2 months. Mean cough severity improved from 4.03 on a visual analogue scale to 2.6 (p < 0.0001), with 0 indicating no cough and 5 indicating the worst cough ever. Iron supplementation was also associated with a significant improvement in cough hyperresponsiveness to histamine inhalation.
Comment: Iron supplementation has previously been shown to reduce the severity of cough that sometimes results from the use of angiotensin-converting enzyme inhibitors. The new study found that cough can be a manifestation of iron deficiency, and that correction of iron deficiency improves the cough. The mechanism by which iron deficiency leads to coughing is unknown.
Bucca C et al. Effect of iron supplementation in women with chronic cough and iron deficiency. Int J Clin Pract. 2012;66:1095–1100.
Antioxidants for Endometriosis Pain
Fifty-nine women (aged 19–41 years) with pelvic pain and a history of endometriosis or infertility who were scheduled for surgery were randomly assigned to receive, in double-blind fashion, 1000 mg per day of vitamin C and 1200 IU per day of vitamin E or placebo for 8 weeks before surgery. The proportion of women who reported a decrease in "everyday pain" was significantly greater in the vitamin group than in the placebo group (43% vs. 0%; p < 0.006). There was a significant decrease in inflammatory markers in the peritoneal fluid of women in the vitamin group.
Comment: Women with endometriosis have been found to have increased oxidative stress in the peritoneal cavity. Oxidative stress can be decreased by antioxidants such as vitamin C and vitamin E. The results of the present study indicate that supplementing with vitamins C and E can decrease pain and inflammation in women with endometriosis.
Santanam N et al. Antioxidant supplementation reduces endometriosis-related pelvic pain in humans. Transl Res. 2013;161:189–195.
Milking Umbilical Cord Beneficial for Babies
Two hundred term or near-term neonates were randomly assigned to have umbilical cord milking (intervention group) or no milking (control group). In both groups the cord was clamped within 30 seconds. In the intervention group the cord was milked after cutting and clamping at 25 cm from the umbilicus. In the control group the cord was clamped 2 to 3 cm from the umbilicus and was not milked. At 6 weeks of age, the mean hemoglobin concentration (11.9 vs. 10.8 g/dl; p < 0.05) and the mean serum ferritin level (356 vs. 178 mcg/L; p < 0.05) were significantly higher in the intervention group than in the control group. The mean serum bilirubin concentration at 48 hours was nonsignificantly higher in the intervention group than in the control group (7.4 vs. 6.6 mg/dl), but none of the infants required phototherapy. No infant developed polycythemia.
Comment: Iron deficiency is one of the most common nutritional problems during the first year of life. In addition to being a component of hemoglobin, iron is essential for brain development. A deficiency of iron during this critical period can result in permanent impairment of brain function.
At the time a baby is born, the placenta and umbilical cord contain a relatively large amount of blood. After delivery, the placenta continues to pulsate in order to deliver that blood to the newborn. If the umbilical cord is allowed to remain open, much of this blood is delivered to the baby through the cord. The volume of this placental "transfusion" amounts to approximately 40 ml of additional blood per kg of body weight. This blood provides about 75 mg of extra iron, an amount sufficient to meet the baby's iron needs for more than three months. Midwives typically wait until the placenta has stopped pulsating before clamping the umbilical cord. However, the common obstetrical practice of clamping the cord almost immediately after the delivery deprives the baby of that additional iron. Previous research has shown that delaying cord clamping by as little as 2 minutes significantly decreases the incidence of iron deficiency and iron-deficiency anemia at age 6 months. Umbilical cord milking, as performed in the present study, is another way to increase the delivery of iron to the baby, although it might be less effective than delaying cord clamping.
Concerns have been raised that pushing more blood into the newborn could increase the risk of hyperbilirubinemia or polycythemia; however, the results of the present study suggest that those concerns are unwarranted.
Upadhyay A et al. Effect of umbilical cord milking in term and near term infants: randomized control trial. Am J Obstet Gynecol. 2013;208:120.e1–120.e6.
Alan R. Gaby, MD